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Query to the research database of the Uni Freiburg for department publications later than 2010. Personal websites might have more complete lists of publications.

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2020

Zurell D, Franklin J, König C, Bouchet PJ, Dormann CF, Elith J, Fandos G, Feng X, Guillera‐Arroita G, Guisan A, Lahoz‐Monfort JJ, Leitão PJ, Park DS, Peterson AT, Rapacciuolo G, Schmatz DR, Schröder B, Serra‐Diaz JM, Thuiller W, Yates KL, Zimmermann NE, Merow C
A standard protocol for reporting species distribution models
2020 Ecography, volume: 43, pages: 1261 - 1277

Abstract Species distribution models (SDMs) constitute the most common class of models across ecology, evolution and conservation. The advent of ready‐to‐use software packages and increasing availability of digital geoinformation have considerably assisted the application of SDMs in the past decade, greatly enabling their broader use for informing conservation and management, and for quantifying impacts from global change. However, models must be fit for purpose, with all important aspects of their development and applications properly considered. Despite the widespread use of SDMs, standardisation and documentation of modelling protocols remain limited, which makes it hard to assess whether development steps are appropriate for end use. To address these issues, we propose a standard protocol for reporting SDMs, with an emphasis on describing how a study's objective is achieved through a series of modeling decisions. We call this the ODMAP (Overview, Data, Model, Assessment and Prediction) protocol, as its components reflect the main steps involved in building SDMs and other empirically‐based biodiversity models. The ODMAP protocol serves two main purposes. First, it provides a checklist for authors, detailing key steps for model building and analyses, and thus represents a quick guide and generic workflow for modern SDMs. Second, it introduces a structured format for documenting and communicating the models, ensuring transparency and reproducibility, facilitating peer review and expert evaluation of model quality, as well as meta‐analyses. We detail all elements of ODMAP, and explain how it can be used for different model objectives and applications, and how it complements efforts to store associated metadata and define modelling standards. We illustrate its utility by revisiting nine previously published case studies, and provide an interactive web‐based application to facilitate its use. We plan to advance ODMAP by encouraging its further refinement and adoption by the scientific community.
Johann F, Handschuh M, Linderoth P, Dormann CF, Arnold J
Adaptation of wild boar (Sus scrofa) activity in a human-dominated landscape
2020 Bmc Ecol, volume: 20, page: 4

Abstract Background Wild boars (Sus scrofa L.) are globally widely distributed, and their populations have increased in Europe during recent decades. Encounters between humans and wild boars are rare because of the predominantly nocturnal lifestyle of the latter, and wild boar management by hunting is a challenging task. Animal activity patterns are important for understanding the behaviour of a species. However, knowledge of detailed temporal patterns and an understanding of the drivers of wild boar activity at a fine temporal scale are lacking. Of special relevance for human–wild boar interactions (e.g., encounters, conflicts, and management) is the question of whether nocturnal activity depends on anthropogenic factors and, particularly, how local hunting regimes may affect activity patterns. We used GPS telemetry and acceleration measurements to shed light on this part of wild boar behaviour, observing 34 animals in Central Europe. Animals were tracked along a gradient of hunting pressure from hunting-free areas to areas with low or high hunting pressure. Fitted generalised additive models allowed predicting the probability of active behaviour under differing disturbance regimes precisely to day of year and time of day. Results The wild boars were predominantly nocturnal, with peak activity at approximately midnight. However, the data showed increased activity during daylight for wild boars that used no-hunting zones or reduced-hunting zones. Large areas with low disturbance levels promoted activity during daylight more than smaller areas with an intermediate disturbance regime. High air temperatures and locations within forests reduced the probability of active behaviour, whereas proximity to tracks used for forestry or agriculture was accompanied by a higher probability of activity. Conclusions We conclude that wild boars flexibly adjust their activity to their local environmental conditions, considering disturbances at the scale of long-term home ranges as well as actual small-scale landscape quality. Entire wild boar home ranges should be covered in the delineation of reserves intending to stimulate activity during daylight.
Dormann CF
Calibrating probability predictions from machine-learning and statistical models
2020 Global Ecol Biogeogr, volume: 27, issue: 4, pages: 760 - 765

Abstract Aim Predictions from statistical models may be uncalibrated, meaning that the predicted values do not have the nominal coverage probability. This is easiest seen with probability predictions in machine‐learning classification, including the common species occurrence probabilities. Here, a predicted probability of, say, .7 should indicate that out of 100 cases with these environmental conditions, and hence the same predicted probability, the species should be present in 70 and absent in 30. Innovation A simple calibration plot shows that this is not necessarily the case, particularly not for overfitted models or algorithms that use non‐likelihood target functions. As a consequence, ‘raw’ predictions from such a model could easily be off by .2, are unsuitable for averaging across model types, and resulting maps hence be substantially distorted. The solution, a flexible calibration regression, is simple and can be applied whenever deviations are observed. Main conclusions ‘Raw’, uncalibrated probability predictions should be calibrated before interpreting or averaging them in a probabilistic way.
Kraan C, Thrush SF, Dormann CF
Co-occurrence patterns and the large-scale spatial structure of benthic communities in seagrass meadows and bare sand
2020 Bmc Ecol, volume: 20, page: 37
Visalli, Morgan E., Best, Benjamin D., Cabral, Reniel B., Cheung, William W.L., Clark, Nichola A., Garilao, Cristina, Kaschner, Kristin, Kesner-Reyes, Kathleen, Lam, Vicky W.Y., Maxwell, Sara M., Mayorga, Juan, Moeller, Holly V., Morgan, Lance, Ortuño Crespo, Guillermo, Pinsky, Malin L., White, Timothy D., McCauley, Douglas J.
Data-driven approach for highlighting priority areas for protection in marine areas beyond national jurisdiction
2020 Mar Policy, volume: 111, pages: 1 - 11

Abstract One of the aims of the United Nations (UN) negotiations on the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction (ABNJ) is to develop a legal process for the establishment of area-based management tools, including marine protected areas, in ABNJ. Here we use a conservation planning algorithm to integrate 55 global data layers on ABNJ species diversity, habitat heterogeneity, benthic features, productivity, and fishing as a means for highlighting priority regions in ABNJ to be considered for spatial pro- tection. We also include information on forecasted species distributions under climate change. We found that parameterizing the planning algorithm to protect at least 30% of these key ABNJ conservation features, while avoiding areas of high fishing effort, yielded a solution that highlights 52,545,634 km2 (23.7%) of ABNJ as high priority regions for protection. Instructing the planning model to avoid ABNJ areas with high fishing effort resulted in relatively minor shifts in the planning solution, when compared to a separate model that did not consider fishing effort. Integrating information on climate change had a similarly minor influence on the plan- ning solution, suggesting that climate-informed ABNJ protected areas may be able to protect biodiversity now and in the future. This globally standardized, data-driven process for identifying priority ABNJ regions for protection serves as a valuable complement to other expert-driven processes underway to highlight ecologically or biologically significant ABNJ regions. Both the outputs and methods exhibited in this analysis can additively inform UN decision-making concerning establishment of ABNJ protected areas.
Siddig AAH, Richardson JS, Dormann CF
Drought may amplify the impacts of salt pollution in pond ecosystems: an experimental exploration
2020 Fundam. Appl. Limnol., volume: 194/1, pages: 1 - 9

Abstract Pond ecosystems are biodiversity-rich habitats, which support great biological diversity and provide important ecological services, but increasingly face risk of pollution and drought events. With increase in use of road-salts, ponds become vulnerable to high levels of salt pollution and may impair their biological communities and ecosystem functions. However, understanding the impacts of these two threats combined are limited. In this study, we experimentally investigated the impacts of road-salt pollution and the expected future increase in drought events on ponds’ physical conditions, communities and ecosystem functions. In a two-way factorial design, 20 experimental mesocosms were used to test the individual and combined effects of climate change-driven drought events and salt pollution on natural pond ecosystems. Treatments were presence or absence of water salinization to mimic pollution by road-salts, and drying to mimic drought events. Our drought treatment doubled water salinity during the experimental period. While salt additions significantly affected ponds’ physical conditions and leaf litter decomposition, both salt additions and drying showed no independent impacts on pond biota and ecosystem functions. However, our path analysis revealed that drying indirectly reduced leaf litter decomposition and ecosystem productivity through changes in ponds’ physical conditions, although it did not affect biomass of insects and periphyton. Overall, our findings suggest that anticipated drought events will amplify road-salt pollution, and subsequently affect ponds’ biodiversity, food webs, and ecosystem functions. Implications for restoration, conservation and climate change adaptation may include actively managing snow-melting salts and long-term monitoring of changes in ponds’ biophysical conditions and ecological functions.
Avila IC, Dormann CF, García C, Payán LF, Zorrilla MX
Early whales: Humpbacks extend their stay in a breeding ground in the Tropical Eastern Pacific
2020 Ices J Mar Sci, volume: 77, pages: 109 - 117

Abstract During the austral winter, G-stock humpback whales, Megaptera novaeangliae, migrate to the Tropical Eastern Pacific to breed. To analyse if the whale migration times have changed over time, we analysed 31 years (1988–2018) of arrival and departure times to Gorgona National Park, Colombia, an important breeding site. During this period, whales have significantly changed their arrival time, coming now earlier, but their departure time has not changed significantly. Hence, humpback whales now stay 1 month longer than 31 years ago. Humpbacks arrived in Gorgona at the earliest during the beginning of May and stayed at the most until late December. The change observed in the arrival time to breeding grounds could be related to ice sheet mass changes in autumn in Antarctica and increase in population size over the past decades but we were unable to determine which factor is more important in explaining the observed trend. Management decisions in Colombia need to account for a longer stay, specifically restricting anthropogenic activities from 1May to 31December. We urge other researchers to review their data, in case this shift is evident in other regions and management plans need to be updated.
Storch I, Penner J, Asbeck T, Basile M, Bauhus J, Braunisch V, Dormann CF, Frey F, Gärtner S, Hanewinkel M, Koch B, Klein AM, Kuss T, Pregernig M, Pyttel P, Reif A, Scherer‐Lorenzen M, Segelbacher G, Schraml U, Staab M, Winkel G, Yousefpour R
Evaluating the effectiveness of retention forestry to enhance biodiversity in production forests of Central Europe using an interdisciplinary, multi‐scale approach
2020 Ecol Evol, volume: 10, issue: 3, pages: 1489 - 1509

Abstract Retention forestry, which retains a portion of the original stand at the time of harvesting to maintain continuity of structural and compositional diversity, has been originally developed to mitigate the impacts of clear‐cutting. Retention of habitat trees and deadwood has since become common practice also in continuous‐cover forests of Central Europe. While the use of retention in these forests is plausible, the evidence base for its application is lacking, trade‐offs have not been quantified, it is not clear what support it receives from forest owners and other stakeholders and how it is best integrated into forest management practices. The Research Training Group ConFoBi (Conservation of Forest Biodiversity in Multiple‐use Landscapes of Central Europe) focusses on the effectiveness of retention forestry, combining ecological studies on forest biodiversity with social and economic studies of biodiversity conservation across multiple spatial scales. The aim of ConFoBi is to assess whether and how structural retention measures are appropriate for the conservation of forest biodiversity in uneven‐aged and selectively harvested continuous‐cover forests of temperate Europe. The study design is based on a pool of 135 plots (1 ha) distributed along gradients of forest connectivity and structure. The main objectives are (a) to investigate the effects of structural elements and landscape context on multiple taxa, including different trophic and functional groups, to evaluate the effectiveness of retention practices for biodiversity conservation; (b) to analyze how forest biodiversity conservation is perceived and practiced, and what costs and benefits it creates; and (c) to identify how biodiversity conservation can be effectively integrated in multi‐functional forest management. ConFoBi will quantify retention levels required across the landscape, as well as the socio‐economic prerequisites for their implementation by forest owners and managers. ConFoBi's research results will provide an evidence base for integrating biodiversity conservation into forest management in temperate forests.
Gutzat F, Dormann CF
Exploration of Concerns about the Evidence-Based Guideline Approach in Conservation Management: Hints from Medical Practice
2020 Environmental Management, volume: 66, pages: 435 - 449

Abstract The importance of using evidence in decision-making is frequently highlighted in policy reports and scientific papers. However, subjective judgments of the reliability of environmental evidence vary widely, and large-scale systematic searches for evidence are only common for climate-related topics. In the medical field, evidence-based guidelines are routinely used to guide treatments. In the management of multiple-use landscapes similar guidelines could substantially narrow the sciencepractice gap but are largely absent. The challenges potential guidelines face are therefore unknown. For the case of forest conservation, we conducted 14 semistructured interviews with mainly forest practitioners and presented them an example medical guideline together with evidence-based statements on forest conservation (hereinafter: statement paper). We identified 28 concerns related to potential evidence-based guidelines in forest conservation. The interviews yielded approximately three major findings. First, recommendations on forest conservation are better accepted if they include clear instructions and are formulated for a specific context. Fragmentary conservation evidence complicates the formulation of specific recommendations. Second, the level of evidence framework, which indicates the strength of the available evidence, is perceived as too complex. Third, neglecting forest multifunctionality in a potential guideline hampers its application but, if addressed, potentially weakens its ecological relevance. We show that major concerns about potential evidence-based conservation guidelines are similar to the challenges experienced by medical guidelines. We also identify concerns unique to forestry.
Janeiro-Otero, Andrea, Newsome, Thomas M., Van Eeden, Lily M., Ripple, William R., Dormann, Carsten F.
Grey wolf (Canis lupus) predation on livestock in relation to prey availability
2020 Biol Conserv, volume: 243, page: 108433
Louis M, Skovrind M, Samaniego Castruita JA, Garilao C, Kaschner K, Gopalakrishnan S, Haile JS, Lydersen C, Kovacs KM, Garde E, Heide-Jorgensen MP, Postma L, Ferguson SH, Willerslev E, Lorenzen ED
Influence of past climate change on phylogeography and demographic history of narwhals, Monodon monoceros.
2020 P Roy Soc Lond B Bio, volume: 287, issue: 1925, page: 20192964

Abstract The Arctic is warming at an unprecedented rate, with unknown consequences for endemic fauna. However, Earth has experienced severe climatic oscillations in the past, and understanding how species responded to them might provide insight into their resilience to near-future climatic predictions. Little is known about the responses of Arctic marine mammals to past climatic shifts, but narwhals (Monodon monoceros) are considered one of the endemic Arctic species most vulnerable to environmental change. Here, we analyse 121 complete mito- chondrial genomes from narwhals sampled across their range and use them in combination with species distribution models to elucidate the influence of past and ongoing climatic shifts on their population structure and demographic his- tory. We find low levels of genetic diversity and limited geographic structuring of genetic clades. We show that narwhals experienced a long-term low effective population size, which increased after the Last Glacial Maximum, when the amount of suitable habitat expanded. Similar post-glacial habitat release has been a key driver of population size expansion of other polar marine predators. Our analyses indicate that habitat availability has been critical to the success of narwhals, raising concerns for their fate in an increasingly warming Arctic.
Dormann CF, Bagnara M, Boch S, Hinderling J, Janeiro-Otero A, Schäfer D, Schall P, Hartig F
Plant species richness increases with light availability, but not variability, in temperate forests understorey
2020 BMC Ecology, volume: 20, issue: 43, pages: 1 - 9

Abstract Background: Temperate forest understorey vegetation poses an excellent study system to investigate whether increases in resource availability lead to an increase in plant species richness. Most sunlight is absorbed by the species-poor tree canopy, making the much more species-rich understorey species inhabit a severely resource-limited habitat. Additionally, the heterogeneity of light availability, resulting from management-moderated tree composition and age structure, may contribute to species coexistence. One would therefore expect that the diversity in the herb layer correlates positively with either the overall light availability, or the light heterogeneity, depending on whether resource availability or heterogeneity are more important drivers of diversity. To test this idea, we assessed variability of light conditions in 75 forest plots across three ecoregions with four diferent methods. Results: We correlated these data with vegetation relevés and found light availability to be strongly positively cor‑ related with understorey plant species richness, as well as with understorey cover. Light variability (assessed with two approaches) within plots was positively correlated with transmittance, but did not improve the relationship further, suggesting that the main driver of species richness in this system is the overall resource availability. Two of the three beech-dominated regions exhibited near-identical efects of light transmittance, while the third, featuring pine along‑ side beech and thus with the longest gradient of transmittance and lowest species richness, displayed a weaker light response. Conclusions: While site conditions are certainly responsible for the trees selected by foresters, for the resulting forest structure, and for the diferences in plant species pools, our results suggest that light transmittance is a strong mediat‑ ing factor of understorey plant species richness. Keywords: Understorey vegetation, Temperate forest, Species richness, Light availability
Ploton P, Mortier F, Réjou-Méchain M, Barbier N, Picard N, Rossi V, Dormann CF, Cornu G, Viennois G, Bayol N, Lyapustin A, Gourlet-Fleury S, Pélissier R
Spatial validation reveals poor predictive performance of large-scale ecological mapping models
2020 Nature Communications, volume: 11, issue: 4540, pages: 1 - 11

Abstract Mapping aboveground forest biomass is central for assessing the global carbon balance. However, current large-scale maps show strong disparities, despite good validation statistics of their underlying models. Here, we attribute this contradiction to a flaw in the validation methods, which ignore spatial autocorrelation (SAC) in data, leading to overoptimistic assessment of model predictive power. To illustrate this issue, we reproduce the approach of large-scale mapping studies using a massive forest inventory dataset of 11.8 million trees in central Africa to train and validate a random forest model based on multispectral and environmental variables. A standard nonspatial validation method suggests that the model predicts more than half of the forest biomass variation, while spatial validation methods accounting for SAC reveal quasi-null predictive power. This study underscores how a common practice in big data mapping studies shows an apparent high predictive power, even when predictors have poor relationships with the ecological variable of interest, thus possibly leading to erroneous maps and interpretations.
Schwarz B, Vázquez DP, CaraDonna PJ, Knight TM, Benadi G, Dormann CF, Gauzens B, Motivans E, Resasco J, Blüthgen N, Burkle LA, Fang Q, Kaiser‐Bunbury CN, Alarcón R, Bain JA, Chacoff NP, Huang S, LeBuhn G, MacLeod M, Petanidou T, Rasmussen C, Simanonok MP, Thompson AH, Fründ J
Temporal scale‐dependence of plant–pollinator networks
2020 Oikos, volume: 129, pages: 1289 - 1302

Abstract The study of mutualistic interaction networks has led to valuable insights into ecological and evolutionary processes. However, our understanding of network structure may depend upon the temporal scale at which we sample and analyze network data. To date, we lack a comprehensive assessment of the temporal scale‐dependence of network structure across a wide range of temporal scales and geographic locations. If network structure is temporally scale‐dependent, networks constructed over different temporal scales may provide very different perspectives on the structure and composition of species interactions. Furthermore, it remains unclear how various factors – including species richness, species turnover, link rewiring and sampling effort – act in concert to shape network structure across different temporal scales. To address these issues, we used a large database of temporally‐resolved plant–pollinator networks to investigate how temporal aggregation from the scale of one day to multiple years influences network structure. In addition, we used structural equation modeling to explore the direct and indirect effects of temporal scale, species richness, species turnover, link rewiring and sampling effort on network structural properties. We find that plant–pollinator network structure is strongly temporally‐scale dependent. This general pattern arises because the temporal scale determines the degree to which temporal dynamics (i.e. phenological turnover of species and links) are included in the network, in addition to how much sampling effort is put into constructing the network. Ultimately, the temporal scale‐dependence of our plant–pollinator networks appears to be mostly driven by species richness, which increases with sampling effort, and species turnover, which increases with temporal extent. In other words, after accounting for variation in species richness, network structure is increasingly shaped by its underlying temporal dynamics. Our results suggest that considering multiple temporal scales may be necessary to fully appreciate the causes and consequences of interaction network structure.
Li HD, Tang L, Jia C, Holyoak M, Fründ J, Huang X, Xiao Z
The functional roles of species in metacommunities, as revealed by metanetwork analyses of bird-plant frugivory networks.
2020 Ecol Lett, volume: in press

Abstract Understanding how biodiversity and interaction networks change across environmental gradients is a major challenge in ecology. We integrated metacommunity and metanetwork perspectives to test species’ functional roles in bird–plant frugivory interactions in a fragmented forest landscape in Southwest China, with consequences for seed dispersal. Availability of fruit resources both on and under trees created vertical feeding stratification for frugivorous birds. Bird–plant interactions involving birds feeding only on-the-tree or both on and under-the-tree (shared) had a higher centrality and contributed more to metanetwork organisation than interactions involving birds feeding only under-the-tree. Moreover, bird–plant interactions associated with large-seeded plants disproportionately contributed to metanetwork organisation and centrality. Consequently, on-the-tree and shared birds contributed more to metanetwork organisation whereas under-the-tree birds were more involved in local processes. We would expect that species’ roles in the metanetwork will translate into different conservation values for maintaining functioning of seed-dispersal networks.
Henrich M, Niederlechner S, Kröschel M, Thoma S, Dormann CF, Hartig F, Heurich M
The influence of camera trap flash type on the behavioural reactions and trapping rates of red deer and roe deer
2020 Remote Sensing in Ecology and Conservation, volume: 6, issue: 3, pages: 399 - 410

Abstract Camera traps have become an important tool in wildlife monitoring. However, an issue in interpreting their data in statistical analyses of population densities, demography or behaviour is that the probability of detecting the target animals and their behaviours may vary depending on environmental and methodological factors. A specific problem is the type of flash used in the camera trap, as animals may react differently to different flash types and change their avoidance or habituation behaviour accordingly over time. Here, we provide the first systematic test of the impact of flash type in studies of red deer (Cervus elaphus) and roe deer (Capreolus capreolus), based on an analysis of behavioural responses to white, standard infrared and black flashes during 900 camera trap deployments in the Bavarian Forest National Park and the Northern Black Forest. The results revealed that both deer species were more likely to react to standard infrared than to black flash, but trigger delays prevented comparisons to white flash. Red deer reacted more frequently to camera traps than did roe deer, and responses were more common in the Northern Black Forest than in the Bavarian Forest National Park, where hunting is severely restricted. Contrary to our expectations, camera trapping rates of free‐ranging deer did not significantly decline over time for any flash type or species. Despite the lack of evidence for avoidance behaviour, we recommend the use of black flash for behavioural studies of deer populations to minimize the risk of introducing a source of disturbance whereas infrared and white flash are equally suitable for determinations of demographic parameters.
Johann, F., Handschuh, M., Linderoth, P., Heurich, M., Dormann, C.F., Arnold, J.
Variability of daily space use in wild boar Sus scrofa
2020 Wildlife Biol, volume: 2020, pages: 1 - 12
Zhao, Qianshuo, Stephenson, Fabrice, Lundquist, Carolyn, Kaschner, Kristin, Jayathilake, Dinusha, Costello, Mark J.
Where Marine Protected Areas would best represent 30% of ocean biodiversity
2020 Biol Conserv, volume: 244, page: 108536

Abstract The IUCN (the International Union for Conservation of Nature) World Conservation Congress called for the full protection of 30% of each marine habitat globally and at least 30% of all the ocean. Thus, we quantitatively prioritized the top 30% areas for Marine Protected Areas (MPAs) globally using global scale measures of biodiversity from the species to ecosystem level. The analysis used (a) Ecosystems mapped based on 20 environmental variables, (b) four Biomes (seagrass, kelp, mangrove, and shallow water coral reefs) plus seabed rugosity as a proxy for habitat, and (c) species richness within each biogeographic Realm (indicating areas of species endemicity), so as to maximise representivity of biodiversity overall. We found that the 30% prioritized areas were mainly on continental coasts, island arcs, oceanic islands, the southwest Indian Ridge, the northern Mid-Atlantic Ridge, the Coral Triangle, Caribbean Sea, and Arctic Archipelago. They generally covered 30% of the Ecosystems and over 80% of the Biomes. Although 58% of the areas were within countries Exclusive Economic Zones (EEZ), only 10% were in MPAs, and < 1% in no-take MPAs (IUCN category Ia). These prioritized areas indicate where it would be optimal to locate MPAs for recovery of marine biodiversity within and outside country's EEZ. Our results thus provide a map that will aid both national and international planning of where to protect marine biodiversity as a whole.

2019

Pinheiro, R. B., Felix, G. M. F., Dormann, C. F., Mello, M. A. R.
A new model explaining the origin of different topologies in interaction networks
2019 Ecology, volume: 100, issue: 9, page: e02796

Abstract Nestedness and modularity have been recurrently observed in species interaction networks. Some studies argue that those topologies result from selection against unstable networks, and others propose that they likely emerge from processes driving the interactions between pairs of species. Here we present a model that simulates the evolution of consumer species using resource species following simple rules derived from the integrative hypothesis of specialization (IHS). Without any selection on stability, our model reproduced all commonly observed network topologies. Our simulations demonstrate that resource heterogeneity drives network topology. On the one hand, systems containing only homogeneous resources form generalized nested networks, in which generalist consumers have higher performance on each resource than specialists. On the other hand, heterogeneous systems tend to have a compound topology: modular with internally nested modules, in which generalists that divide their interactions between modules have low performance. Our results demonstrate that all real-world topologies likely emerge through processes driving interactions between pairs of species. Additionally, our simulations suggest that networks containing similar species differ from heterogeneous networks and that modules may not present the topology of entire networks.
Hauenstein, S., Kshatriya, M., Blanc, J., Dormann, C. F., Beale, C. M.
African elephant poaching rates correlate with local poverty, national corruption and global ivory price
2019 Nat Commun, volume: 10, page: 2242

Abstract Poaching is contributing to rapid declines in elephant populations across Africa. Following high-profile changes in the political environment, the overall number of illegally killed elephants in Africa seems to be falling, but to evaluate potential conservation interventions we must understand the processes driving poaching rates at local and global scales. Here we show that annual poaching rates in 53 sites strongly correlate with proxies of ivory demand in the main Chinese markets, whereas between-country and between-site variation is strongly associated with indicators of corruption and poverty. Our analysis reveals a recent decline in annual poaching mortality rate from an estimated peak of over 10% in 2011 to <4% in 2017. Based on these findings, we suggest that continued investment in law enforcement could further reduce poaching, but is unlikely to succeed without action that simultaneously reduces ivory demand and tackles corruption and poverty.
Bagnara, M., Silveyra Gonzalez, R., Reifenberg, S., Steinkamp, J., Hickler, T., Werner, C., Dormann, C. F., Hartig, F.
An R package facilitating sensitivity analysis, calibration and forward simulations with the LPJ-GUESS dynamic vegetation model
2019 Environ Modell Softw, volume: 111, pages: 55 - 60

Abstract Dynamic global vegetation models (DGVMs) are of crucial importance for understanding and predicting vegetation, carbon, nitrogen and water dynamics of ecosystems in response to climate change. Their complexity, however, creates challenges for model analysis and data integration. A solution is to interface DGVMs with established statistical computing environments. Here we introduce rLPJGUESS, an R-package that couples the widely used DGVM LPJ-GUESS with the R environment for statistical computing, making existing R-packages and functions readily available to perform complex analyses with this model. We demonstrate the advantages of this framework by using rLPJGUESS to perform several otherwise laborious tasks: first, a set of single simulations, followed by global and local sensitivity analyses, a Bayesian calibration with a Markov-Chain Monte Carlo (MCMC) algorithm, and a predictive simulation with multiple climate scenarios. Our example highlights the opportunities of interfacing existing models in earth and environmental sciences with state-of-the-art computing environments such as R.
Berberich, G. M., Klimetzek, D., Paraschiv, M., Stancioiu, P. T., Grumpe, A.
Biogeostatistics confirm: Even a low total number of red wood ant nests provide new information on tectonics in the East Carpathian Orogen (Romania)
2019 Ecol Indic, volume: 101, pages: 486 - 500

Abstract Recent statistical analyses revealed that the spatial distribution of nests of red wood ants (RWA; Formica rufa-group) and actively degassing fault zone are strongly correlated. We now applied the modified Hough Transform (mHT) and Iterative Mode Detection (IMD) to RWA nest positions in four study areas of the Eastern Carpathian Orogen. The aim of this analysis was (1) to evaluate relationships between spatial distribution of RWA nests and complex tectonic stress regimes in the Eastern Carpathian Orogen, (2) to test if this procedure is also applicable even when only a low total number of RWA nests is available, and (3) to further verify the validity of this statistic approach. By applying a double-blind study, we minimized bias by researchers’ preconceptions. Since irregular shapes of the study areas were found to strongly influence the findings of distribution patterns, all subsequent analyses were carried out for circular areas. Statistical results substantiated our hypothesis that RWA nest distributions clearly show very pronounced directions even in complex tectonic environments such as the Eastern Carpathian Orogen. Dominant NW-SE directions (scattering between 120° and 150°) are corresponding to the 1st order regional stress field in the East Carpathians. Additionally, our analyses revealed the 2nd order stress field in NE-SW orientation. Furthermore, directions of re-activated shear systems, e.g. from Late Miocene and Pliocene that had been modified by overprinting due to changes of the main stress field, could be identified. For the Moldavian and East European Platform, which are characterized by thick sediment cover, our analyses could significantly contribute to otherwise concealed tectonics. Furthermore, the mode of some faults identified in previous tectonic studies could be complemented and specified and assigned to the corresponding tectonic regime. Our study thus confirms the validity of our statistic approach even when the total number of RWA nests is low.
Lautenbach, S., Mupepele, A.-C., Dormann, C. F., Lee, H., Schmidt, S., Scholte, S. S. K., Seppelt, R., van Teeffelen, A. J. A., Verhagen, W., Volk, M.
Blind spots in ecosystem services research and challenges for implementation
2019 Reg Environ Change, pages: 1 - 22

Abstract Ecosystem service research is high on the policy agenda. Strategies to synthesize individual success stories and derive generalized results to provide guidance for policymakers and stakeholder is central to many science-policy initiatives, such as Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and The Economics of Ecosystems and Biodiversity. However, generalization requires the documentation of basic information on methods and results of case studies, which might not be present throughout all case studies. We used a quantitative review based on a random sample of studies published in the ISI Web of Knowledge between 1996 and 2016 to identify blind spots in ecosystem service research that might hinder the generalization. We structured our analysis along critical questions about five facets that characterize the holistic ideal of ecosystem services research: (i) social-ecological validity of ecosystem data and models, (ii) consideration of trade-offs between ecosystem services, (iii) recognition of off-site effects, (iv) comprehensive and shrewd involv ement of stakeholders, and (v) relevance and usability of study results for the operationalization of the ecosystem service concept in practice. Results show that these facets were not addressed by the majority of case studies including more recent studies. Clusters of ecosystem services studied together were prone to different blind spots. To effectively operationalize the concept of ecosystem services, the blind spots need to be addressed by upcoming studies. A list of critical questions is provided to raise the awareness of the blind spots both for synthesis of existing knowledge and for future research agendas.
Lautenbach S, Mupepele AC, Dormann CF, Lee H, Schmidt S, Scholte SSK, Seppelt R, van Teeffelen AJA, Verhagen W, Volk M
Blind spots in ecosystem services research and challenges for implementation
2019 Reg Environ Change, volume: 19, pages: 2151 - 2172

Abstract Ecosystem service research is high on the policy agenda. Strategies to synthesize individual success stories and derive generalized results to provide guidance for policymakers and stakeholder is central to many science-policy initiatives, such as Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and The Economics of Ecosystems and Biodiversity. However, generalization requires the documentation of basic information on methods and results of case studies, which might not be present throughout all case studies. We used a quantitative review based on a random sample of studies published in the ISI Web of Knowledge between 1996 and 2016 to identify blind spots in ecosystem service research that might hinder the generalization. We structured our analysis along critical questions about five facets that characterize the holistic ideal of ecosystem services research: (i) social-ecological validity of ecosystem data and models, (ii) consideration of trade-offs between ecosystem services, (iii) recognition of off-site effects, (iv) comprehensive and shrewd involv ement of stakeholders, and (v) relevance and usability of study results for the operationalization of the ecosystem service concept in practice. Results show that these facets were not addressed by the majority of case studies including more recent studies. Clusters of ecosystem services studied together were prone to different blind spots. To effectively operationalize the concept of ecosystem services, the blind spots need to be addressed by upcoming studies. A list of critical questions is provided to raise the awareness of the blind spots both for synthesis of existing knowledge and for future research agendas.
Patenaude G, Lautenbach S, Paterson JS, Locatelli T, Dormann CF, Metzger MJ, Walz A
Breaking the environmental services glass ceiling: realising impact
2019 Reg Environ Change, volume: 19, pages: 2261 - 2274

Abstract Through changes in policy and practice, the inherent intent of the ecosystem services (ES) concept is to safeguard ecosystems for human wellbeing. While impact is intrinsic to the concept, little is known about how and whether ES science leads to impact. Evidence of impact is needed. Given the lack of consensus on what constitutes impact, we differentiate between attributional impacts (transitional impacts on policy, practice, awareness or other drivers) and consequential impacts (real, on-the-ground impacts on biodiversity, ES, ecosystem functions and human wellbeing) impacts. We conduct rigorous statistical analyses on three extensive databases for evidence of attributional impact (the form most prevalently reported): the IPBES catalogue (n = 102), the Lautenbach systematic review (n = 504) and a 5-year in-depth survey of the OPERAs Exemplars (n = 13). To understand the drivers of impacts, we statistically analyse associations between study characteristics and impacts. Our findings show that there exists much confusion with regard to defining ES science impacts, and that evidence of attributional impact is scarce: only 25% of the IPBES assessments self-reported impact (7% with evidence); in our meta-analysis of Lautenbach’s systematic review, 33% of studies provided recommendations indicating intent of impacts. Systematic impact reporting was imposed by design on the OPERAs Exemplars: 100% reported impacts, suggesting the importance of formal impact reporting. The generalised linear models and correlations between study characteristics and attributional impact dimensions highlight four characteristics as minimum baseline for impact: study robustness, integration of policy instruments into study design, stakeholder involvement and type of stakeholders involved. Further in depth examination of the OPERAs Exemplars showed that study characteristics associated with impact on awareness and practice differ from those associated with impact on policy: to achieve impact along specific dimensions, bespoke study designs are recommended. These results inform targeted recommendations for ES science to break its impact glass ceiling.
Hauenstein, S., Fattebert, J., Grüebler, M. U., Naef‐Daenzer, B., Pe'er, G., Hartig, F.
Calibrating an individual‐based movement model to predict functional connectivity for little owls.
2019 Ecol Appl, volume: 29, issue: 4, page: e01873

Abstract Dispersal is crucial for population viability and thus a popular target for conservation measures. However, the ability of individuals to move between habitat patches is notoriously difficult to estimate. One solution is to quantify functional connectivity via realistic individual‐based movement models. Such simulation models, however, are difficult to build and even more difficult to parameterize. Here, we use the example of natal little owl (Athene noctua) dispersal to develop a new analysis chain for the calibration of individual‐based dispersal models using a hybrid of statistical parameter estimation and Approximate Bayesian Computation (ABC). Specifically, we use locations of 126 radio‐tracked juveniles to first estimate habitat utilization by generalized additive models (GAMs) and the biased random bridges (BRB) method. We then include the estimated parameters in a spatially explicit individual‐based model (IBM) of little owl dispersal and calibrate further movement parameters using ABC. To derive efficient summary statistics, we use a new dimension reduction method based on random forest (RF) regression. Finally, we use the calibrated IBM to predict the dispersal potential of little owls from local populations in southwestern Germany to suitable habitat patches in northern Switzerland. We show that pre‐calibrating habitat preference parameters while inferring movement behavioral parameters via ABC is a computationally efficient solution to obtain a plausible IBM parameterization. We also find that dimension reduction via RF regression outperforms the widely used least squares regression, which we applied as a benchmark approach. Estimated movement parameters for the individuals reveal plausible inter‐individual and inter‐sexual differences in movement behavior during natal dispersal. In agreement with a sex‐biased dispersal distance in little owls, females show longer individual flights and higher directional persistence. Simulations from the fitted model indicate that a (re)colonization of northern Switzerland is generally possible, albeit restricted. We conclude that the presented analysis chain is a sensible work‐flow to assess dispersal connectivity across species and ecosystems. It embraces species‐ and individual‐specific behavioral responses to the landscape and allows likelihood‐based calibration, despite an irregular sampling design. Our study highlights existing, yet narrow dispersal corridors, which may require enhancements to facilitate a recolonization of little owl habitat patches in northern Switzerland.
Greyson-Gato, C. J., McCann, K. S., Fründ, J., Lucarotti, C. J., Smith, M. A., Eveleigh, E. S.
Coherent whole food web responses to outbreaking spruce budworm
2019 BioRxiv, page: Preprint

Abstract The world is astoundingly variable, and individuals to whole communities must respond to variability to survive. One potent example of nature’s variability is the massive fluctuations in spruce budworm (Choristoneura fumiferana Clemens) populations that occur over 35 years. We examined how the parasitoid community altered its parasitism of budworm and other caterpillars in response to these fluctuations. Budworm and other caterpillar species were sampled from balsam fir in three plots for 13 years in Atlantic Canada. These caterpillars were reared to identify any emerging parasitoids. We found that the parasitoid community showed a simple linear, and indiscriminate, response (i.e., no preference and so densities purely dictated parasitism rates) to changes in budworm densities relative to other caterpillar species on balsam fir. Furthermore, we observed strong changes in topology and distributions of interaction strengths. These observations suggest parasitoid movement between hardwood stands and balsam fir stands is integral to the population dynamics of budworm. Furthermore, our study remarkably shows that species communities coherently alter species interactions in response to variable resources, fundamentally shifting food web pathways in a manner similar to generalist apex predators.
Daniel S. Karpa, Rebecca Chaplin-Kramer, Timothy D. Meehan, Emily A. Martin, Fabrice DeClerck, Heather Grab, Claudio Gratton, Lauren Hunt, Ashley E. Larsen, Alejandra Martínez-Salinas, Megan E. O’Rourke, Adrien Rusch, Katja Poveda, Mattias Jonsson, Jay A. Rosenheim, Nancy A. Schellhorn, Teja Tscharntke, Stephen D. Wratten, Wei Zhang, Aaron L. Iverson, Lynn S. Adler, Matthias Albrecht, Audrey Alignier, Gina M. Angelella, Muhammad Zubair Anjum, Jacques Avelino, Péter Batáry, Johannes M. Baveco, Felix J. J. A. Bianchi, Klaus Birkhofer, Eric W. Bohnenblusta, Riccardo Bommarco, Michael J. Brewer, Berta Caballero-López, Yves Carrière, Luísa G. Carvalheiro, Luis Cayuela, Mary Centrell, Aleksandar Cetkovic, Dominic Charles Henri, Ariane Chabert, Alejandro C. Costamagna, Aldo De la Mora, Joop de Kraker, Nicolas Desneux, Eva Diehl, Tim Diekötter, Carsten F. Dormann, James O. Eckberg, Martin H. Entling, Daniela Fiedler, Pierre Franck, F. J. Frank van Veen, Thomas Frank, Vesna Gagic, Michael P. D. Garratt, Awraris Getachew, David J. Gonthier, Peter B. Goodell, Ignazio Graziosi, Russell L. Groves, Geoff M. Gurr, Zachary Hajian-Forooshani, George E. Heimpel, John D. Herrmann, Anders S. Huseth, Diego J. Inclán, Adam J. Ingrao, Phirun Iv, Katja Jacot, Gregg A. Johnson, Laura Jones, Marina Kaiser, Joe M. Kaser, Tamar Keasar, Tania N. Kim, Miriam Kishinevsky, Douglas A. Landis, Blas Lavandero, Claire Lavignet, Anne Le Ralec, Debissa Lemessa, Deborah K. Letourneau, Heidi Liere, Yanhui Lu, Yael Lubin, Tim Luttermoser, Bea Maas, Kevi Mace, Filipe Madeira, Viktoria Mader, Anne Marie Cortesero, Lorenzo Marini, Eliana Martine, Holly M. Martinson, Philippe Menozzi, Matthew G. E. Mitchell, Tadashi Miyashita, Gonzalo A. R. Molina, Marco A. Molina-Montenegro, Matthew E. O’Neal, Itai Opatovsky, Sebaastian Ortiz-Martinez, Michael Nash, Örjan Östman, Annie Ouin, Damie Pak, Daniel Paredes, Soroush Parsa, Hazel Parry, Ricardo Perez-Alvarez, David J. Perovic, Julie A. Peterson, Sandrine Petit, Stacy M. Philpott, Manuel Plantegenest, Milan Plecas, Therese Pluess, Xavier Pons, Simon G. Potts, Richard F. Pywell, David W. Ragsdale, Tatyana A. Rand, Lucie Raymond, Benoît Ricci, Chris Sargent, Jean-Pierre Sarthou, Julia Saulais, Jessica Schäckermann, Nick P. Schmidt, Gudrun Schneider, Christof Schüepp, Frances S. Sivakoff, Henrik G. Smith, Kaitlin Stack Whitney, Sonja Stutz, Zsofia Szendrei, Mayura B. Takada, Hisatomo Taki, Giovanni Tamburini, Linda J. Thomson, Yann Tricault, Noelline Tsafack, Matthias Tschumi, Muriel Valantin-Morison, Mai Van Trinh, Wopke van der Werf, Kerri T. Vierling, Ben P. Werling, Jennifer B. Wickens, Victoria J. Wicken, Ben A. Woodcock, Kris Wyckhuys, Haijun Xiao, Mika Yasuda, Akira Yoshioka, Yi Zou
Crop pests and predators exhibit inconsistent responses to surrounding landscape composition
2019 P Natl Acad Sci Usa, volume: 115, issue: 33, pages: E7863 - E7870

Abstract The idea that noncrop habitat enhances pest control and repre- sents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes bene- fits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be bi- ological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model nat- ural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across stud- ies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain vari- ation across studies, though prediction did improve when compar- ing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bol- ster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conser- vation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.

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Dupke, C., Dormann, C. F., Heurich, M.
Does Public Participation Shift German National Park Priorities Away from Nature Conservation?
2019 Environ Conserv, volume: 46, pages: 84 - 91

Abstract National park management has the dual mission of protecting and conserving natural systems and providing services to visitors. These two goals are often contradictory, especially when levels of recreation and tourism increase. We studied whether and how the management of the 13 terrestrial national parks in Germany respond to increasing numbers of visitors. One to three managers from each national park completed an online questionnaire and were then interviewed by phone. We found no general strategy for managing high levels of recreational use. Adaptation to increasing visitor numbers seemed to be complex and arduous. Management options are particularly constrained by the mandatory public participation process, in which various stakeholders are involved in decision-making. Given the political pressure to make amends for restrictions imposed by designated protected areas, national park management is characterized by compromises, which results in a shift of priorities from conservation towards service provision. We argue that to maintain the balance between the dual objectives of conservation and recreation, park managers need the support of both social and biological research communities. Above all, the unique ecological merits of national parks could be more strongly highlighted to increase the general public’s acceptance of park restrictions.
Vollhardt, I. M. C., Ye, Z., Parth, N., Rennstam Rubbmark, O. R., Fründ, J., Traugott, M.
Influence of plant fertilisation on cereal aphid-primary parasitoid-secondary parasitoid networks in simple and complex landscapes.
2019 Agr Ecosyst Environ, volume: 281, pages: 47 - 55

Abstract Agricultural intensification can impact agrobiodiversity in several ways such as in terms of population densities, community composition and food web interactions across all trophic levels. This effect can be investigated at two scales: field-scale and landscape scale. Here it was assessed how the impact of fertilisation (within field) and landscape complexity (within landscape) impact cereal aphid-primary parasitoid-secondary parasitoid systems in winter wheat in Germany. A newly developed molecular technique was used to quantify species-specific linkages between aphids, primary parasitoids and secondary parasitoids sampled in fertilised and unfertilised plots in either simple or complex structured landscapes. The results show a stronger effect of fertilisation than landscape complexity on the groups: fertilisation positively affected the crop plants while it negatively affected both the density of the cereal aphid Sitobion avenae and its primary parasitism rates whereas no effect on the level of secondary parasitism rates was observed. Landscape complexity had no effect on plants, aphids, as well as on primary parasitism rate. In case of secondary parasitism rate there was an effect in interaction with sampling date. Field identity accounted for the strongest effect on parasitoid community composition (10.6% of the variance) from all tested variables, while fertilisation and landscape complexity had almost no effect (1.1% and no effect). Nevertheless, a weak cascading effect of both environmental factors could be observed as the primary-secondary parasitoid network structure responded to both. However, these observed effects on food webs strongly depended on species identity, highlighting the need of species-level food web assessment.
Grady, J. M., Maitner, B. S., Winter, A. S., Kaschner, K., Tittensor, D. P., Record, S., Smith, F. A., Wilson, A. M., Dell, A. I., Zarnetske, P. L., Wearing, H. J., Alfaro, B., Brown, J.H.
Metabolic asymmetry and the global diversity of marine predators
2019 Science, volume: 363, page: 366

Abstract One of the most general patterns in ecology is that diversity increases toward the equator. In the ocean, however, mammal and bird richness generally peak in colder, temperate waters. This pattern is especially puzzling given the thermal stress that cold water imposes on warmbodied endotherms, which must maintain constant, elevated body temperatures through metabolic activity. In contrast, ectothermic fish and reptiles that rely on ambient heat to regulate their body temperature show the highest diversity in tropical and subtropical habitats.
Adedoja, O., Dormann, C. F., Kehinde, T., Samways, M. J.
Refuges from fire maintain pollinator–plant interaction networks
2019 Ecol Evol, volume: 9, pages: 5777 - 5786

Abstract Fire is a major disturbance factor in many terrestrial ecosystems, leading to landscape transformation in fire‐prone areas. Species in mutualistic interactions are often highly sensitive to disturbances like fire events, but the degree and complexity of their responses are unclear. We use bipartite insect–flower interaction networks across a recently burned landscape to explore how plant–pollinator interaction networks respond to a recent major fire event at the landscape level, and where fire refuges were present. We also investigate the effectiveness of these refuges at different elevations (valley to hilltop) for the conservation of displaced flower‐visiting insects during fire events. Then, we explore how the degree of specialization of flower‐visiting insects changes across habitats with different levels of fire impact. We did this in natural areas in the Greater Cape Floristic Region (GCFR) biodiversity hotspot, which is species rich in plants and pollinators. Bees and beetles were the most frequent pollinators in interactions, followed by wasps and flies. Highest interaction activity was in the fire refuges and least in burned areas. Interactions also tracked flower abundance, which was highest in fire refuges in the valley and lowest in burned areas. Interactions consisted mostly of specialized flower visitors, especially in refuge areas. The interaction network and species specialization were lowest in burned areas. However, species common to at least two fire classes showed no significant difference in species specialization. We conclude that flower‐rich fire refuges sustain plant–pollinator interactions, especially those involving specialized species, in firedisturbed landscape. This may be an important shelter for specialized pollinator species at the time that the burned landscape goes through regrowth and succession as part of ecosystem recovery process after a major fire event.
Gustafsson, L., Bauhus, J., Asbeck, T., Augustynczik, A. L. D., Basile, M., Frey, J., Gutzat, F., Hanewinkel, M., Helbach, J., Jonker, M., Knuff, A., Messier, C., Penner, J., Pyttel, P., Reif, A., Storch, F., Winiger, N., Winkel, G., Yousefpour, R., Storch, I.
Retention as an integrated biodiversity conservation approach for continuous-cover forestry in Europe.
2019 Ambio, pages: 1 - 13

Abstract Retention forestry implies that biological legacies like dead and living trees are deliberately selected and retained beyond harvesting cycles to benefit biodiversity and ecosystem functioning. This model has been applied for several decades in even-aged, clearcutting (CC) systems but less so in uneven-aged, continuous-cover forestry (CCF). We provide an overview of retention in CCF in temperate regions of Europe, currently largely focused on habitat trees and dead wood. The relevance of current meta-analyses and many other studies on retention in CC is limited since they emphasize larger patches in open surroundings. Therefore, we reflect here on the ecological foundations and socio-economic frameworks of retention approaches in CCF, and highlight several areas with development potential for the future. Conclusions from this perspective paper, based on both research and current practice on several continents, although highlighting Europe, are also relevant to other temperate regions of the world using continuous-cover forest management approaches.
Fechter, D., Ciuti, S., Kelle, D., Pratje, P., Dormann, C. F., Storch, I.
Spatial behavior in rehabilitated orangutans in Sumatra: Where do they go?
2019 Plos One, volume: 14, issue: 5, page: e0215284

Abstract Wildlife restoration is one of the key components of conservation strategies, and this includes the rehabilitation and release of animals confiscated from wildlife traffickers. When primates are re-introduced, most individuals need a pre-release training to acquire the skills needed to survive in the wild. Pre-release training may either negatively or positively affect primate post-release behavior and survival. Post-release behavior, however, has rarely been monitored even though it is the only means to assess the survival of released individuals. Here, we present a thorough analysis of data from a 3-year radio tracking study on 32 orangutans (Pongo abelii) released in Sumatra after their rehabilitation. We investigated whether and how the age at release, the duration of the pre-release rehabilitation and training, and the release location affected the post-release individual spatial behavior. Orangutans released at older age exhibited post-release habitat selection patterns that were more comparable to that shown by wild conspecifics, i.e., they chose areas closer to rivers and at lower elevations (150–250 meters a.s.l.) where previous research had documented greater food availability. In contrast, individuals released at younger age showed a stronger spatial dependency on the rehabilitation station and exhibited disrupted habitat selection patterns; although after several months after the release all individuals tended to decrease their spatial reliance on the rehabilitation facility. This study indicates that the rehabilitation of individuals for a longer period and their release further from the rehabilitation station have facilitated the subsequent development of more natural spatial behavior, i.e. driven by food availability rather than by the dependence on care-giving human facility. Our study provides indications on how to improve the rehabilitation and release of confiscated orangutans, highlighting the importance of the age at release, the length of the rehabilitation program, and the location of the release site.
Araújo, M. B., Anderson, R. P., Barbosa, A. M., Beale, C. M., Dormann, C. F., Early, R., Garcia, R. A., Guisan, A., Maiorano, L., Naimi, B., O’Hara, R. B., Zimmermann, N. E., Rahbek, C.
Standards for distribution models in biodiversity assessments
2019 Sci Adv, volume: 5, page: eaat4858

Abstract Demand for models in biodiversity assessments is rising, but which models are adequate for the task? We propose a set of best-practice standards and detailed guidelines enabling scoring of studies based on species distribution models for use in biodiversity assessments. We reviewed and scored 400 modeling studies over the past 20 years using the proposed standards and guidelines. We detected low model adequacy overall, but with a marked tendency of improvement over time in model building and, to a lesser degree, in biological data and model evaluation. We argue that implementation of agreed-upon standards for models in biodiversity assessments would promote transparency and repeatability, eventually leading to higher quality of the models and the inferences used in assessments. We encourage broad community participation toward the expansion and ongoing development of the proposed standards and guidelines.
Emily A. Martin, Matteo Dainese, Yann Clough, Andreas Baldi, Riccardo Bommarco, Vesna Gagic, Michael P.D. Garratt, Andrea Holzschuh, David Kleijn, Aniko Kovacs-Hostyanszki, Lorenzo Marini, Simon G. Potts, Henrik G. Smith, Diab Al Hassan, Matthias Albrecht, Georg K.S. Andersson, Josep D. Asıs, Stephanie Aviron, Mario V. Balzan, Laura Banos-Picon, Ignasi Bartomeus, Peter Batary, Francoise Burel, Berta Caballero-Lopez, Elena D. Concepcion, Valerie Coudrain, Juliana Dänhardt, Mario Diaz, Tim Diekötter, Carsten F. Dormann, Remi Duflot, Martin H. Entling, Nina Farwig, Christina Fischer, Thomas Frank, Lucas A. Garibaldi, John Hermann, Felix Herzog, Diego Inclan, Katja Jacot, Frank Jauker, Philippe Jeanneret, Marina Kaiser, Jochen Krauss, Violette Le Feon, Jon Marshall, Anna-Camilla Moonen, Gerardo Moreno, Verena Riedinger, Maj Rundlöf, Adrien Rusch, Jeroen Scheper, Gudrun Schneider, Christof Schüepp, Sonja Stutz, Louis Sutter, Giovanni Tamburini, Carsten Thies, Jose Tormos, Teja Tscharntke, Matthias Tschumi, Deniz Uzman, Christian Wagner, Muhammad Zubair-Anjum, Ingolf Steffan-Dewenter
The interplay of landscape composition and configuration: new pathways to manage functional biodiversity and agroecosystem services across Europe
2019 Ecol Lett, volume: 22, pages: 1083 - 1094

Abstract Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habi- tats) and configuration (edge density) on arthropods in fields and their margins, pest control, pol- lination and yields. Configuration effects interacted with the proportions of crop and non-crop habitats, and species’ dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7- and 1.4-fold respectively. Arable-dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services.
Manning, P., Loos, J., Barnes, A. D., Batáry, P., Bianchi, F. J. J. A., Buchmann, N., De Deyn, G. B., Ebeling, A., Eisenhauer, N., Fischer, M., Fründ, J., Grass, I., Isselstein, J., Jochum, M., Klein, A. M., Klingenberg, E. O. F., Landis, D. A., Lepš, J., Lindborg, R., Meyer, S. T., Temperton, V., Westphal, C., Tscharntke, T.
Transferring biodiversity ecosystem function research to the management of ‘real world’ ecosystems
2019 Adv Ecol Res, page: In press

Abstract Biodiversity-ecosystem functioning (BEF) research grew rapidly following concerns that biodiversity loss would negatively affect ecosystem functions and the ecosystem services they underpin. However, despite evidence that biodiversity strongly affects ecosystem functioning, the influence of BEF research upon policy and the management of ‘real-world’ ecosystems, i.e., semi-natural habitats and agroecosystems, has been limited. Here, we address this issue by classifying BEF research into three clusters based on the degree of human control over species composition and the spatial scale, in terms of grain, of the study, and discussing how the research of each cluster is best suited to inform particular fields of ecosystem management. Research in the first cluster, small-grain highly controlled studies, is best able to provide general insights into mechanisms and to inform the management of species-poor and highly managed systems such as croplands, plantations, and the restoration of heavily degraded ecosystems. Research from the second cluster, small-grain observational studies, and species removal and addition studies, may allow for direct predictions of the impacts of species loss in specific semi-natural ecosystems. Research in the third cluster, large-grain uncontrolled studies, may best inform landscape-scale management and national-scale policy. We discuss barriers to transfer within each cluster and suggest how new research and knowledge exchange mechanisms may overcome these challenges. To meet the potential for BEF research to address global challenges, we recommend transdisciplinary research that goes beyond these current clusters and considers the social-ecological context of the ecosystems in which BEF knowledge is generated. This requires recognizing the social and economic value of biodiversity for ecosystem services at scales, and in units, that matter to land managers and policy makers.

2018

Benadi, G., Gegear, R. J.
Adaptive Foraging of Pollinators Can Promote Pollination of a Rare Plant Species
2018 Am Nat, volume: 192, issue: 2, pages: E81 - E92

Abstract Most pollinators have the foraging flexibility to visit a wide variety of plant species. Yet few studies of pollinator-mediated processes in plants have considered the effects of variation in individual foraging patterns on plant reproductive success. In this study, we use an individual-based model of pollinator foraging economics to predict how visitation rates and pollination success of two coflowering plant species change with their frequency (relative abundance). Whereas previous studies suggested that adaptive foraging of pollinators always favors pollination of abundant plant species (positive frequency dependence), here we show that under certain conditions the per capita pollination success of a rare plant species can exceed that of a more abundant species. Specifically, when the overall flower density is sufficiently high and pollinators’ perception ranges are sufficiently large, animals with limited memory of previously encountered rewards forage in a way that favors pollination of the rarer plant species. Moreover, even with perfectly informed foragers, a rare plant species benefits more from offering a higher floral reward than a more abundant species. Our results show that adaptive foraging of individual pollinators can have important implications for plant community dynamics and the persistence of rare plant species.
Ciuti, S., Tripke, H., Antkowiak, P., Silveyra Gonzalez, R., Dormann, C. F., Heurich, M.
An efficient method to exploit LiDAR data in animal ecology
2018 Methods Ecol Evol, volume: 9, pages: 893 - 904

Abstract 1. Light detection and ranging (LiDAR) technology provides ecologists with high- resolution data on three-dimensional vegetation structure. Large LiDAR datasets challenge predictive ecologists, who commonly simplify point clouds into structural attributes (namely LiDAR-based metrics such as canopy height), which are used as predictors in ecological models, potentially with loss of relevant information. 2. We illustrate an efficient alternative approach to reduce the dimensionality of LiDAR data that aims at minimal data filtering with no a priori assumptions on the ecology of the target species. We first fit the ecological model exploiting the full variability in the LiDAR point cloud, then we explain the results using post-model- ling LiDAR-data classification for ecological interpretation only. This is the classical logic of explorative, hypothesis generating and predictive statistics, rather than testing specific vegetation-structural hypotheses. 3. First, we reduce the dimensionality of the LiDAR point cloud by principal compo- nent analysis (PCA) to fewer predictors. Second, we show that LiDAR-PCs are ca- pable to outperforming commonly used environmental predictors in ecological modelling, including LiDAR-based metrics. We exemplify this by modelling red deer (Cervus elaphus) and roe deer (Capreolus capreolus) resource selection in the Bavarian Forest National Park, Germany. After fitting the ecological model, we provide an interpretation of the information included in LiDAR-PCs, which allows users to draw conclusions whenever using them as predictors. We make use of the PCA rotation matrix and post-modelling data classification, and document deer selection for understorey vegetation at unprecedented fine scale. 4. OurapproachisthefirstattemptinanimalecologytoavoidtheuseofLiDAR-based metrics as model predictors, but rather generate principal components able to cap- ture most of the LiDAR point cloud variability. Our study demonstrates that LiDAR- PCs can boost ecological models. We envision a potential use of LiDAR-PCs in several applications, particularly species distribution and habitat suitability models. We demonstrate an application of our approach by building suitability maps for both deer species, which can be used by practitioners to visualize model spatial predictions and understand the type of forest structures selected by deer.
Mannocci, L., Roberts, J. J., Halpin, P. N., Authier, M., Boisseau, O., Bradai, M. N., Cañadas, A., Chicote, C., David, L., Di-Méglio, N., Fortuna, C. M., Frantzis, A., Gazo, M., Genov, T., Hammond, P. S., Holcer, D., Kaschner, K., Kerem, D., Lauriano, G., Lewis, T., Notarbartolo di Sciara, G., Panigada, S., Raga, J. A., Scheinin, A., Ridoux, V., Vella, A., Vella, J.
Assessing cetacean surveys throughout the Mediterranean Sea: a gap analysis in environmental space
2018 Sci Rep-uk, volume: 8, issue: 3126

Abstract Heterogeneous data collection in the marine environment has led to large gaps in our knowledge of marine species distributions. To fill these gaps, models calibrated on existing data may be used to predict species distributions in unsampled areas, given that available data are sufficiently representative. Our objective was to evaluate the feasibility of mapping cetacean densities across the entire Mediterranean Sea using models calibrated on available survey data and various environmental covariates. We aggregated 302,481 km of line transect survey effort conducted in the Mediterranean Sea within the past 20 years by many organisations. Survey coverage was highly heterogeneous geographically and seasonally: large data gaps were present in the eastern and southern Mediterranean
Bagnara, M., Van Oijen, M., Cameron, D., Gianelle, D., Magnani, F., Sottocornola, M.
Bayesian calibration of simple forest models with multiplicative mathematical structure: A case study with two Light Use Efficiency models in an alpine forest
2018 Ecol Model, volume: 371, pages: 90 - 100

Abstract Forest models are increasingly being used to study ecosystem functioning, through simulation of carbon fluxes and productivity in different biomes and plant functional types all over the world. Several forest models based on the concept of Light Use Efficiency (LUE) rely mostly on a simplified mathematical structure and empirical parameters, require little amount of data to be run, and their computations are usually fast. However, possible calibration issues must be investigated in order to ensure reliable results. Here we addressed the important issue of delayed convergence when calibrating LUE models, characterized by a multiplicative structure, with a Bayesian approach. We tested two models (Prelued and the Horn and Schulz (2011a) model), applying three Markov Chain Monte Carlo-based algorithms with different number of iterations, and different sets of prior parameter distributions with increasing information content. The results showed that recently proposed algorithms for adaptive calibration did not confer a clear advantage over the Metropolis–Hastings Random Walk algorithm for the forest models used here, and that a high number of iterations is required to stabilize in the convergence region. This can be partly explained by the multiplicative mathematical structure of the models, with high correlations between parameters, and by the use of empirical parameters with neither ecological nor physiological meaning. The information content of the prior distributions of the parameters did not play a major role in reaching convergence with a lower number of iterations. We conclude that there is a need for a more careful approach to calibration to solve potential problems when applying models characterized by a multiplicative mathematical structure. Moreover, the calibration proved time consuming and mathematically difficult, so advantages of using a computationally fast and user-friendly model were lost due to the calibration process needed to obtain reliable results.
Dormann, C. F., Bobrowski, M., Dehling, D. M., Harris, D. J., Hartig, F., Lischke, H., Moretti, M. D., Pagel, J., Pinkert, S., Schleuning, M., Schmidt, I. S., Sheppard, C. S., Steinbauer, M. J., Zeuss, D., Kraan, C.
Biotic interactions in species distribution modelling: 10 questions to guide interpretation and avoid false conclusions
2018 Global Ecol Biogeogr, volume: 27, pages: 1004 - 1016

Abstract Aim: Recent studies increasingly use statistical methods to infer biotic interactions from cooccurrence information at a large spatial scale. However, disentangling biotic interactions from other factors that can affect co-occurrence patterns at the macroscale is a major challenge. Approach: We present a set of questions that analysts and reviewers should ask to avoid erroneously attributing species association patterns to biotic interactions. Our questions relate to the appropriateness of data and models, the causality behind a correlative signal, and the problems associated with static data from dynamic systems. We summarize caveats reported by macroecological studies of biotic interactions and examine whether conclusions on the presence of biotic interactions are supported by the modelling approaches used. Findings: Irrespective of the method used, studies that set out to test for biotic interactions find statistical associations in species’ co-occurrences. Yet, when compared with our list of questions, few purported interpretations of such associations as biotic interactions hold up to scrutiny. This does not dismiss the presence or importance of biotic interactions, but it highlights the risk of too lenient interpretation of the data. Combining model results with information from experiments and functional traits that are relevant for the biotic interaction of interest might strengthen conclusions. Main conclusions: Moving from species- to community-level models, including biotic interactions among species, is of great importance for process-based understanding and forecasting ecological responses. We hope that our questions will help to improve these models and facilitate the interpretation of their results. In essence, we conclude that ecologists have to recognize that a species association pattern in joint species distribution models will be driven not only by real biotic interactions, but also by shared habitat preferences, common migration history, phylogenetic history and shared response to missing environmental drivers, which specifically need to be discussed and, if possible, integrated into models.
Vonderach, C., Kändler, G., Dormann, C. F.
Consistent set of additive biomass functions for eight tree species in Germany fit by nonlinear seemingly unrelated regression
2018 Ann Forest Sci, volume: 75, page: 49

Abstract •Key message Biomass functions are relevant for an easy and quick estimation of tree biomass. Nevertheless, additive biomass functions for different species and different components have not been published for the area of Germany, yet. Now, we present a set of additive biomass functions for estimating component and total mass for eight species and up to nine components. •Context Biomass functions are relevant for an easy and quick estimation of tree biomass, e.g. for carbon budget calculation. Component-specific functions offer even more detail and can be used to answer questions about, e.g., biomass allocation to different components, (nutrient) element stock and flows or the amount and re-distribution of harvested biomass and its consequences. • Aims Since there exists no published additive biomass functions in the context of Germany, we aimed at providing such equations for different species and different components using a comprehensive data set from different sources. • Methods We collected several data sets for eight relevant tree species (Norway spruce, n = 1150 trees; Silver fir, n = 31; Douglas fir, n = 161; Scots pine, n = 460; European beech, n = 918; Oak, n = 313; Sycamore, n = 28 and European ash, n = 37) in Germany and adjacent countries, homogenised the component information, imputed missing values and applied nonlinear seemingly unrelated regression to eight (for deciduous trees species) respectively nine (for conifereous species) components simultaneously. • Results The collected data set contains trees from 7 cm diameter in breast height to around 80 cm. From this broad data basis, we established two sets of additive biomass functions: a simple model using the predictors diameter in breast height and tree height as well as a more elaborate model using up to six predictors. • Conclusion Finally, we can present additive models for the eight relevant tree species in Germany. Models for Silver fir, European ash and Sycamore are rather limited in their model range due to their input data; the other models are based on a broad range of predictors and are considered to be broadly applicable.
Karp, D. S., Chaplin-Kramer, R., Meehan, T. D., Martin, E. A., DeClerck, F., Grab, H., Gratton, C., Hunt, L., Larsen, A. E., Martínez-Salinas, A., O’Rourke, M. E., Rusch, A., Poveda, K., Jonsson, M., Rosenheim, J. A., Schellhorn, N. A., Tscharntke, T., Wratten, S. D., Zhang, W., Iverson, A. L., Adler, L. S., Albrecht, M., Alignier, A., Angelella, G. M., Anjum, M. Z., Avelino, J., Batáry, P., Baveco, J. M., Bianchi, F. J. J. A., Birkhofer, K., Bohnenblust, E. W., Bommarco, R., Brewer, M. J., Caballero-López, B., Carrière, Y., Carvalheiro, L. G., Cayuela, L., Centrella, M., Ćetković, A., Henri, D. C., Chabert, A., Costamagna, A. C., De la Mora, A., de Kraker, J., Desneux, N., Diehl, E., Diekötter, T., Dormann, C. F., Eckberg, J. E., Entling, M. H., Fiedler, D., Franck, P., van Veen, F. J. F., Frank, T., Gagic, V., Garratt, M. P. D., Getachew, A., Gonthier, D. J., Goodell, P. B, Graziosi, I., Groves, R. L., Gurr, G. M., Hajian-Forooshani, Z., Heimpel, G. E., Herrmann, J. D., Huseth, A. S., Inclán, D. J., Ingrao, A. J., Iv, P., Jacot, K., Johnson, G. A., Jones, L., Kaiser, M., Kaser, J. M., Keasar, T., Kim, T. N., Kishinevsky, M., Landis, D. A., Lavandero, B., Lavigne, C., Le Ralec, A., Lemessa, D., Letourneau, D. K., Liere, H., Lu, Y., Lubin, Y., Luttermoser, T., Maas, B., Mace, K., Madeira, F., Mader, V., Cortesero, A. M., Marini, L., Martinez, E., Martinson, H. M., Menozzi, P., Mitchell, M. G. E., Miyashita, T., Molina, G. A. R., Molina-Montenegro, M. A., O’Neal, M. E., Opatovsky, I., Ortiz-Martinez, S., Nash, M., Östman, Ö., Ouin, A., Pak, D., Paredes, D., Parsa, S., Parry, H., Perez-Alvarez, R., Perović, D. J., Peterson, J. A., Petit, S., Philpott, S. M., Plantegenest, M., Plećaš, M., Pluess, T., Pons, X., Potts, S. G., Pywell, R. F., Ragsdale, D. W., Rand, T. A., Raymond, L., Ricci, B., Sargent, C., Sarthou, J.-P., Saulais, J., Schäckermann, J., Schmidt, N. P., Schneider, G., Schüepp, C., Sivakoff, F. S., Smith, H.G., Whitney, K.S., Stutz, S., Szendrei, Z., Takada, M. B., Taki, H., Tamburini, G., Thomson, L. J., Tricault, Y., Tsafack, N., Tschumi, M., Valantin-Morison, M., Van Trinh, M., van der Werf, W., Vierling, K. T., Werling, B. P., Wickens, J. B., Wickens, V. J., Woodcock, B. A., Wyckhuys, K., Xiao, H., Yasuda, M., Yoshioka, A., Zou, Y.
Crop pests and predators exhibit inconsistent responses to surrounding landscape composition
2018 P Natl Acad Sci Usa, volume: 115, issue: 33, pages: E7863 - E7870

Abstract The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.
Game, E. T., Tallis, H., Olander, L., Alexander, S. M., Busch, J., Cartwright, N., Kalies, E. L., Masuda, Y. J., Mupepele, A.-M., Qiu, J., Rooney, A., Sills, E., Sutherland, W. J.
Cross-discipline evidence principles for sustainability policy
2018 Nature Sustainability, volume: 1, pages: 452 - 454

Abstract Evidence-based approaches to sustainability challenges must draw on knowledge from the environment, development and health communities. To be practicable, this requires an approach to evidence that is broader and less hierarchical than the standards often applied within disciplines.
Avila, I. C., Kaschner, K., Dormann, C. F.
Current global risks to marine mammals: Taking stock of the threats
2018 Biol Conserv, volume: 221, pages: 44 - 58

Abstract Marine mammals are impacted by many anthropogenic activities and mitigating these impacts requires knowledge about the geographic occurrence of threats. Here, we systematically reviewed, categorized and georeferenced information from > 1780 publications about threats affecting 121 marine mammal species worldwide between 1991 and 2016. We created risk maps by assigning threat to countries where they had been reported, further refining spatial allocation to specific ocean basins and Longhurst biogeographical provinces and subsequent intersection with mapped species' distributions. We superimposed risk maps for different taxa and threats to visualize geographic patterns of risks and quantify risk severity with respect to number of species affected. Almost all marine mammal species have been reported to face at least one threat. Incidental catch affected the most species (112 species), followed by pollution (99 species), direct harvesting (89 species) and traffic-related impacts (86 species). Direct human activities, mainly fisheries, urban development, whaling/ hunting and tourism were the major source of threats affecting most species (> 60 species). Risk areas were identified for 51% of marine mammal core habitat. Besides, the majority of local marine mammal communities are at high-risk in 47% of world coastal-waters. Hotspots were located mainly in temperate and polar coastal waters and in enclosed seas such as the Mediterranean or Baltic Sea. However, risk areas differed by threat types and taxa. Our maps show that human activities in coastal waters worldwide impose previously unrecognized levels of cumulative risk for most of marine mammal species, and provide a spatially explicit frame of reference for the assessment of mammals' species conservation status.
Gutzat, F., Dormann, C. F.
Decaying trees improve nesting opportunities for cavity‐nesting birds in temperate and boreal forests: A meta‐analysis and implications for retention forestry
2018 Ecol Evol, volume: 8, pages: 8616 - 8626

Abstract Many studies have dealt with the habitat requirements of cavity‐nesting birds, but there is no meta‐analysis on the subject and individual study results remain vague or contradictory. We conducted a meta‐analysis to increase the available evidence for nest‐site selection of cavity‐nesting birds. Literature was searched in Web of Science and Google Scholar and included studies that provide data on the habitat requirements of cavity‐nesting birds in temperate and boreal forests of varying naturalness. To compare nest and non‐nest‐tree characteristics, the following data were collected from the literature: diameter at breast height (DBH) and its standard deviation (SD), sample size of trees with and without active nest, amount of nest and available trees described as dead or with a broken crown, and amount of nest and available trees that were lacking these characteristics. Further collected data included bird species nesting in the cavities and nest‐building type (nonexcavator/excavator), forest type (coniferous/deciduous/mixed), biome (temperate/boreal), and naturalness (managed/natural). From these data, three effect sizes were calculated that describe potential nest trees in terms of DBH, vital status (dead/alive), and crown status (broken/intact). These tree characteristics can be easily recognized by foresters. The results show that on average large‐diameter trees, dead trees, and trees with broken crowns were selected for nesting. The magnitude of this effect varied depending primarily on bird species and the explanatory variables forest type and naturalness. Biome had lowest influence (indicated by ΔAIC). We conclude that diameter at breast height, vitality, and crown status can be used as tree characteristics for the selection of trees that should be retained in selectively harvested forests.
Morin, P. A., Foote, A. D., Baker, C. S., Hancock-Hanser, B. L., Kaschner, K., Mate, B. R., Mescnick, S. L., Pease, V. L., Rosel, P. E., Alexander, A.
Demography or selection on linked cultural traits or genes? Investigating the driver of low mtDNA diversity in the sperm whale using complementary mitochondrial and nuclear genome analyses.
2018 Mol Ecol, volume: 27, pages: 2604 - 2619

Abstract Mitochondrial DNA has been heavily utilized in phylogeography studies for several decades. However, underlying patterns of demography and phylogeography may be misrepresented due to coalescence stochasticity, selection, variation in mutation rates, and cultural hitchhiking (linkage of genetic variation to culturally transmitted traits affecting fitness). Cultural hitchhiking has been suggested as an explanation for low genetic diversity in species with strong social structures, counteracting even high mobility, abundance and limited barriers to dispersal. One such species is the sperm whale, which shows very limited phylogeographic structure and low mtDNA diversity despite a worldwide distribution and large population. Here, we use analyses of 175 globally distributed mitogenomes and three nuclear genomes to evaluate hypotheses of a population bottleneck/expansion versus a selective sweep due to cultural-hitchhiking or selection on mtDNA as the mechanism contributing to low worldwide mitochondrial diversity in sperm whales. In contrast to mtDNA control region (CR) data, mitogenome haplotypes are largely ocean-specific, with only one of 80 shared between the Atlantic and Pacific. Demographic analyses of nuclear genomes suggest low mtDNA diversity is consistent with a global reduction in population size that ended approximately 125,000 years ago, correlated with the Eemian interglacial. Phylogeographic analysis suggests that extant sperm whales descend from maternal lineages endemic to the Pacific during the period of reduced abundance, and have subsequently colonized the Atlantic several times. Results highlight the apparent impact of past climate change, and suggest selection and hitchhiking are not the sole processes responsible for low mtDNA diversity in this highly social species.
Mupepele, A.- C., Goebel, A., Dormann, C. F.
Die Evidenzgrundlage von Biodiversität und Ökosystemdienstleistungen in europäischen Agroforestsystemen
2018 BfN-Skripten, volume: 487, pages: 153 - 157

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Gutiérrez-Chacón, C., Dormann, C. F., Klein, A.-M.
Forest-edge associated bees benefit from the proportion of tropical forest regardless of its edge length
2018 Biol Conserv, volume: 220, pages: 149 - 160

Abstract Natural areas are important for wild bees in human-dominated landscapes as they provide permanent feeding and nesting resources. Understanding how bee communities vary with the amount of natural areas is thus key to guide conservation measures. This information, however, is largely lacking in montane tropical ecosystems. Here we explore to what extent the amount of forest area or forest edge (as landscape variables) influence the species richness and abundance of forest-edge associated bees in the Colombian Andes. In addition, we assess the effects of flower species richness and abundance (as local variables) to better understand the individual and interactive effects of forest conservation. Bees were surveyed along 20 forest edges differing in forest proportion and forest edge length within four spatial scales (250, 500, 1000 and 1500m radii). We conducted trait-specific analyses as bees with different traits associated to body size, sociality and nesting behavior might differ in their response to local and landscape variables. We found that overall bee species richness and abundance increased with an increasing proportion of forest within 1000m radius, but also with flower abundance. Similarly, the species richness and abundance of social, large and above-ground nesting bees increased with an increasing proportion of forest area, mainly within 500 and 1000m radii. However, only the abundance (not the species richness) of solitary and small bees were positively related to the proportion of forest within 1000 m. Below-ground nesters did not respond to the individual effect of forest area at any spatial scale. Interactive effects between local and landscape variables were mainly found between flower richness and the proportion of forest. Forest edge length influenced only the abundance of solitary bees. These findings highlight the importance of conserving and/or restoring forest areas – at meaningful spatial scales – to promote diverse bee communities in montane tropical regions.
Everaars, J., Settele, J., Dormann, C. F.
Fragmentation of nest and foraging habitat affects time budgets of solitary bees, their fitness and pollination services, depending on traits: Results from an individual-based model
2018 Plos One, volume: 13, issue: 2, page: e0188269.

Abstract Solitary bees are important but declining wild pollinators. During daily foraging in agricultural landscapes, they encounter a mosaic of patches with nest and foraging habitat and unsuitable matrix. It is insufficiently clear how spatial allocation of nesting and foraging resources and foraging traits of bees affect their daily foraging performance. We investigated potential brood cell construction (as proxy of fitness), number of visited flowers, foraging habitat visitation and foraging distance (pollination proxies) with the model SOLBEE (simulating pollen transport by solitary bees, tested and validated in an earlier study), for landscapes varying in landscape fragmentation and spatial allocation of nesting and foraging resources. Simulated bees varied in body size and nesting preference. We aimed to understand effects of landscape fragmentation and bee traits on bee fitness and the pollination services bees provide, as well as interactions between them, and the general consequences it has to our understanding of the system. This broad scope gives multiple key results. 1) Body size determines fitness more than landscape fragmentation, with large bees building fewer brood cells. High pollen requirements for large bees and the related high time budgets for visiting many flowers may not compensate for faster flight speeds and short handling times on flowers, giving them overall a disadvantage compared to small bees. 2) Nest preference does affect distribution of bees over the landscape, with cavity-nesting bees being restricted to nesting along field edges, which inevitably leads to performance reductions. Fragmentation mitigates this for cavity-nesting bees through increased edge habitat. 3) Landscape fragmentation alone had a relatively small effect on all responses. Instead, the local ratio of nest to foraging habitat affected bee fitness positively through reduced local competition. The spatial coverage ofpollination increases steeply in response to this ratio for all bee sizes. The nest to foraging habitat ratio, a strong habitat proxy incorporating fragmentation could be a promising and practical measure for comparing landscape suitability for pollinators. 4) The number of flower visits was hardly affected by resource allocation, but predominantly by bee size. 5) In landscapes with the highest visitation coverage, bees flew least far, suggesting that these pollination proxies are subject to a trade-off between either longer pollen transport distances or a better pollination coverage, linked to how nests are distributed over the landscape rather than being affected by bee size.
Benadi, G., Pauw, A.
Frequency dependence of pollinator visitation rates suggests that pollination niches can allow plant species coexistence
2018 J Ecol, volume: 106, pages: 1892 - 1901

Abstract 1. How do many species coexist within a trophic level? Resource niches are the classical answer, but in plants which share a small set of abiotic resources, the possibilities for resource partitioning are limited. One possible explanation is that plant species have different pollination niches, with each species specialized to a subset of the available animal species. If this pollinator partitioning results in negative frequency dependence such that each plant species’ reproduction is reduced when it becomes abundant, pollination niches could maintain plant diversity, provided that the strength of negative frequency dependence is sufficient to overcome fitness inequalities between species. 2. We tested this idea by quantifying the effect of species relative abundance on pollinator visitation rate in a 7,000 m2 plot of South African Fynbos vegetation. In addition, we quantified the effect of intraspecific abundance variation at a smaller spatial scale (9 m2 plots), documented species’ pollination niches, and tested the importance of pollinators for seed set in a subset of the plant species. 3. We found that visitation rate indeed declined sharply across the 33 plant species with increasing abundance, but visitation rate was also somewhat depressed in very rare species such that the resulting relationship between visitation rate and relative abundance was hump-shaped. Pollinator niche partitioning among plant species was evident, but less pronounced than in many other studies. Visitation rate was slightly higher in more generalized species, suggesting that they have access to a larger pollination resource. At the intraspecific level and smaller spatial scale, results were less clear and varied among species. Pollinators enhanced seed set in most species. 4. Synthesis. The results imply that, above an abundance threshold, intraspecific competition for pollination could limit the reproduction of common species, thus promoting plant species coexistence. However, the rarest plant species could become extinct due to pollen limitation, that is, an Allee effect. In addition, interactions with pollinators may introduce frequency-independent fitness differences between plant species, thereby increasing the strength of negative frequency dependence required for stable coexistence. These findings shed new light on the role of the pollination niche in plant coexistence.
Dormann, C. F., Calabrese, J. M., Guillera‐Arroita, G., Matechou, E., Bahn, V., Bartoń, K., Beale, C. M., Ciuti, S., Elith, J., Gerstner, K., Guelat, J., Keil, P., Lahoz‐Monfort, J. J., Pollock, L. J., Reineking, B., Roberts, D. R., Schröder, B., Thuiller, W., Warton, D. I., Wintle, B. A., Wood, S. N., Wüest, R. O., Hartig, F.
Model averaging in ecology: a review of Bayesian, information-theoretic, and tactical approaches for predictive inference
2018 Ecol Monogr, volume: 88, issue: 4, pages: 485 - 504

Abstract In ecology, the true causal structure for a given problem is often not known, and several plausible models and thus model predictions exist. It has been claimed that using weighted averages of these models can reduce prediction error, as well as better reflect model selection uncertainty. These claims, however, are often demonstrated by isolated examples. Analysts must better understand under which conditions model averaging can improve predictions and their uncertainty estimates. Moreover, a large range of different model averaging methods exists, raising the question of how they differ in their behaviour and performance. Here, we review the mathematical foundations of model averaging along with the diversity of approaches available. We explain that the error in model-averaged predictions depends on each model’s predictive bias and variance, as well as the covariance in predictions between models, and uncertainty about model weights. We show that model averaging is particularly useful if the predictive error of contributing model predictions is dominated by variance, and if the covariance between models is low. For noisy data, which predominate in ecology, these conditions will often be met. Many different methods to derive averaging weights exist, from Bayesian over information-theoretical to cross-validation optimized and resampling approaches. A general recommendation is difficult, because the performance of methods is often context dependent. Importantly, estimating weights creates some additional uncertainty. As a result, estimated model weights may not always outperform arbitrary fixed weights, such as equal weights for all models.When averaging a set of models with many inadequate models, however, estimating model weights will typically be superior to equal weights.We also investigate the quality of the confidence intervals calculated for model-averaged predictions, showing that they differ greatly in behaviour and seldom manage to achieve nominal coverage. Our overall recommendations stress the importance of non-parametric methods such as cross-validation for a reliable uncertainty quantification of model-averaged predictions.
Yates, K. L., Bouchet, P. J., Caley, M. J., Mengersen, K., Randin, C. F., Parnell, S., Fielding, A. H., Bamford, A. J., Ban, S., Barbosa, A. M., Dormann, C. F., Elith, J., Embling, C. B., Ervin, G. N., Fisher, R., Gould, S., Graf, R. F., Gregr, E. J., Halpin, P. N., Heikkinen, R. K., Heinänen, S., Jones, A. R., Krishnakumar, P. K., Lauria, V., Lozano-Montes, H., Mannocci, L., Mellin, C., Mesgaran, M. B., Moreno-Amat, E., Mormede, S., Novaczek, E., Oppel, S., Ortuño Crespo, G., Peterson, A. T., Rapacciuolo, G., Roberts, J. J., Ross, R. E., Scales, K. L., Schoeman, D., Snelgrove, P., Sundblad, G., Thuiller, W., Torres, L. G., Verbruggen, H., Wang, L., Wenger, S., Whittingham, M. J., Zharikov, Y., Zurell, D., Sequeira, A. M. M.
Outstanding Challenges in the Transferability of Ecological Models
2018 Trends Ecol Evol, volume: 33, issue: 10

Abstract Predictive models are central to many scientific disciplines and vital for informing management in a rapidly changing world. However, limited understanding of the accuracy and precision of models transferred to novel conditions (their ‘trans- ferability’) undermines confidence in their predictions. Here, 50 experts identified priority knowledge gaps which, if filled, will most improve model transfers. These are summarized into six technical and six fundamental challenges, which underlie the combined need to intensify research on the determinants of ecological predictability, including species traits and data quality, and develop best prac- tices for transferring models. Of high importance is the identification of a widely applicable set of transferability metrics, with appropriate tools to quantify the sources and impacts of prediction uncertainty under novel conditions.
Storch, F., Dormann, C. F., Bauhus, J.
Quantifying forest structural diversity based on large-scale inventory data: a new approach to support biodiversity monitoring
2018 for Ecosyst, volume: 5, page: 34

Abstract Background: The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to quantify structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed, for example to support biodiversity monitoring. The existing approaches to quantify forest structural diversity are based on small geographical regions or single forest types, typically using only small data sets. Results: Here we developed an index of structural diversity based on National Forest Inventory (NFI) data of Baden- Württemberg, Germany, a state with 1.3 million ha of diverse forest types in different ownerships. Based on a literature review, 11 aspects of structural diversity were identified a priori as crucially important to describe structural diversity. An initial comprehensive list of 52 variables derived from National Forest Inventory (NFI) data related to structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of structural diversity. These variables comprise 1) quadratic mean diameter at breast height (DBH), 2) standard deviation of DBH, 3) standard deviation of stand height, 4) number of decay classes, 5) bark-diversity index, 6) trees with DBH ≥ 40 cm, 7) diversity of flowering and fructification, 8) average mean diameter of downed deadwood, 9) mean DBH of standing deadwood, 10) tree species richness and 11) tree species richness in the regeneration layer. These variables were combined into a simple, additive index to quantify the level of structural diversity, which assumes values between 0 and 1. We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse structural diversity in large-scale forest inventories. Conclusions: The forest structure index presented here can be derived in a similar way from standard inventory variables for most other large-scale forest inventories to provide important information about biodiversity relevant forest conditions and thus provide an evidence-base for forest management and planning as well as reporting.
Beale, C. M., Hauenstein, S., Mduma, S., Frederick, H., Jones, T., Bracebridge, C., Maliti H., Kija, H., Kohi, E. M.
Spatial analysis of aerial survey data reveals correlates of elephant carcasses within a heavily poached ecosystem
2018 Biol Conserv, volume: 218, pages: 258 - 267

Abstract Growth of the illegal wildlife trade is a key driver of biodiversity loss, with considerable research focussing on trafficking and trade, but rather less focussed on supply. Elephant poaching for ivory has driven a recent population decline in African elephants and is a typical example of illegal wildlife trade. Some of the heaviest poaching has been in Southern Tanzania's Ruaha-Rungwa ecosystem. Using data from three successive aerial surveys and modern spatial analysis techniques we identify the correlates of elephant carcasses within the ecosystem, from which important information about how poachers operate can be gleaned. Carcass density was highest close to wet-season (but not dry season) waterholes, at higher altitudes and at intermediate travel cost from villages. We found no evidence for an ecosystem-wide impact of ranger patrol locations on carcass abundance, but found strong evidence that different ranger posts showed contrasting patterns in relation to carcasses, some being significantly associated with clusters of carcasses, others showing the expected negative correlation and most showing no pattern at all. Despite a spatial change in elephant carcass locations between years, we find little evidence to suggest poachers have changed their behaviour in relation to key modelled covariates. Our maps of poaching activity can feed directly into anti-poaching control measures, but also provide general insights into how illegal harvest of high value wildlife products occurs in the field, and our spatio-temporal analysis provides a valuable analysis framework for aerial survey data from protected areas globally.
Benneter, A., Forrester, D. I., Bouriaud, O., Dormann, C. F., Bauhus, J.
Tree species diversity does not compromise stem quality in major European forest types
2018 Forest Ecol Manag, volume: 422, pages: 323 - 337

Abstract Mixed-species forests can have higher productivity, in terms of wood volume, than monospecific forests. In addition, higher tree species richness has been found to positively correlate with multiple ecosystem services and functions. Surprisingly, stem quality as one of the most important factors regarding the economic value of forests has rarely been formally studied in diverse forests. This paper aims at investigating how tree species richness influences stem quality and which factors may drive quality development in these stands. Stem quality, understood here essentially as the suitability of a particular stem for particular end-uses, is influenced by a tree's ability to capture sufficient resources for growth and is influenced by neighbouring trees, e.g. through shading and physical crown interactions. We collected data on crown size, stem form and tree health for over 12,000 trees in 209 study plots in six European regions (Finland, Germany, Poland, Romania, Italy and Spain) within naturally diverse forests to assess the impact of tree species richness on these characteristics. Results showed that quality variability between regions, stands and individual trees was high across species. At the stand level, there was a slight tendency towards lower stem quality with increasing diversity. However, individual trees of high quality were present at all diversity levels and for all target species. Tree species richness could not be confirmed as a primary influence on stem quality at the stand level. Rather, stand and individual tree properties such as structural composition, competition, tree size and crown characteristics were identified as the main factors for stem quality development, even in mixed stands. Many of the factors identified in this study can be directly or indirectly influenced by forest management strategies tailored to produce high-quality timber in mixed-species forests. Our findings suggest that diverse stands are not inferior regarding stem quality, while at the same time being able to provide various other ecosystem services.
El Gabbas, A., Dormann, C. F.
Wrong, but useful: regional species distribution models may not be improved by range-wide data under biased sampling.
2018 Ecol Evol, volume: 8, pages: 2196 - 2206

Abstract Species distribution modeling (SDM) is an essential method in ecology and conservation. SDMs are often calibrated within one country's borders, typically along a limited environmental gradient with biased and incomplete data, making the quality of these models questionable. In this study, we evaluated how adequate are national presence-only data for calibrating regional SDMs. We trained SDMs for Egyptian bat species at two different scales: only within Egypt and at a species-specific global extent. We used two modeling algorithms: Maxent and elastic net, both under the point-process modeling framework. For each modeling algorithm, we measured the congruence of the predictions of global and regional models for Egypt, assuming that the lower the congruence, the lower the appropriateness of the Egyptian dataset to describe the species' niche. We inspected the effect of incorporating predictions from global models as additional predictor (“prior”) to regional models, and quantified the improvement in terms of AUC and the congruence between regional models run with and without priors. Moreover, we analyzed predictive performance improvements after correction for sampling bias at both scales. On average, predictions from global and regional models in Egypt only weakly concur. Collectively, the use of priors did not lead to much improvement: similar AUC and high congruence between regional models calibrated with and without priors. Correction for sampling bias led to higher model performance, whatever prior used, making the use of priors less pronounced. Under biased and incomplete sampling, the use of global bats data did not improve regional model performance. Without enough bias-free regional data, we cannot objectively identify the actual improvement of regional models after incorporating information from the global niche. However, we still believe in great potential for global model predictions to guide future surveys and improve regional sampling in data-poor regions.

2017

O'Hara, C. C., Afflerbach, J. C., Scarborough, C., Kaschner, K., Halpern, B. S.
Aligning marine species range data to better serve science and conservation
2017 Plos One, volume: 12, issue: 5, page: e0175739

Abstract Species distribution data provide the foundation for a wide range of ecological research studies and conservation management decisions. Two major efforts to provide marine species distributions at a global scale are the International Union for Conservation of Nature (IUCN), which provides expert-generated range maps that outline the complete extent of a species' distribution; and AquaMaps, which provides model-generated species distribution maps that predict areas occupied by the species. Together these databases represent 24,586 species (93.1% within AquaMaps, 16.4% within IUCN), with only 2,330 shared species. Differences in intent and methodology can result in very different predictions of species distributions, which bear important implications for scientists and decision makers who rely upon these datasets when conducting research or informing conservation policy and management actions. Comparing distributions for the small subset of species with maps in both datasets, we found that AquaMaps and IUCN range maps show strong agreement for many well-studied species, but our analysis highlights several key examples in which introduced errors drive differences in predicted species ranges. In particular, we find that IUCN maps greatly overpredict coral presence into unsuitably deep waters, and we show that some AquaMaps computer-generated default maps (only 5.7% of which have been reviewed by experts) can produce odd discontinuities at the extremes of a species’ predicted range. We illustrate the scientific and management implications of these tradeoffs by repeating a global analysis of gaps in coverage of marine protected areas, and find significantly different results depending on how the two datasets are used. By highlighting tradeoffs between the two datasets, we hope to encourage increased collaboration between taxa experts and large scale species distribution modeling efforts to further improve these foundational datasets, helping to better inform science and policy recommendations around understanding, managing, and protecting marine biodiversity.
Weatherdon, L. V., Appeltans, W., Bowles-Newark, N., Brooks, T. M., Davis, F. E., Despot-Belmonte, K., Fletcher, S., Garilao, C., Hilton-Taylor, C., Hirsch, T., Juffe-Bignoli, D., Kaschner, K., Kingston, N., Malsch, K., Regan, E. C., Kesner-Reyes, K., Rose, D. C., Wetzel, F. T., Wilkinson, T., Martin, C. S.
Blueprints of Effective Biodiversity and Conservation Knowledge Products That Support Marine Policy
2017 Front. Mar. Sci.

Abstract Biodiversity and conservation data are generally costly to collect, particularly in the marine realm. Hence, data collected for a given—often scientific—purpose are occasionally contributed toward secondary needs, such as policy implementation or other types of decision-making. However, while the quality and accessibility of marine biodiversity and conservation data have improved over the past decade, the ways in which these data can be used to develop and implement relevant management and conservation measures and actions are not always explicit. For this reason, there are a number of scientifically-sound datasets that are not used systematically to inform policy and decisions. Transforming these marine biodiversity and conservation datasets into knowledge products that convey the information required by policy- and decision-makers is an important step in strengthening knowledge exchange across the science-policy interface. Here, we identify seven characteristics of a selection of online biodiversity and conservation knowledge products that contribute to their ability to support policy- and decision-making in the marine realm (as measured by e.g., mentions in policy resolutions/decisions, or use for reporting under selected policy instruments; use in high-level screening for areas of biodiversity importance). These characteristics include: a clear policy mandate; established networks of collaborators; iterative co-design of a user-friendly interface; standardized, comprehensive and documented methods with quality assurance; consistent capacity and succession planning; accessible data and value-added products that are fit-for-purpose; and metrics of use collated and reported. The outcomes of this review are intended to: (a) support data creators/owners/providers in designing and curating biodiversity and conservation knowledge products that have greater influence, and hence impact, in policy- and decision-making, and (b) provide recommendations for how decision- and policy-makers can support the development, implementation, and sustainability of robust biodiversity and conservation knowledge products through the framing of marine policy and decision-making frameworks.
Roberts, D. R., Bahn, V., Ciuti, S., Boyce, M. S., Elith, J., Guillera-Arroita, G., Hauenstein, S., Lahoz-Monfort, J. J., Schröder, B., Thuiller, W., Warton, D. I., Wintle, B. A., Hartig, F., Dormann, C. F.
Cross-validation strategies for data with temporal, spatial, hierarchical, or phylogenetic structure.
2017 Ecography, volume: 40, pages: 913 - 929

Abstract Ecological data often show temporal, spatial, hierarchical (random effects), or phylogenetic structure. Modern statistical approaches are increasingly accounting for such dependencies. However, when performing cross-validation, these structures are regularly ignored, resulting in serious underestimation of predictive error. One cause for the poor performance of uncorrected (random) cross-validation, noted often by modellers, are dependence structures in the data that persist as dependence structures in model residuals, violating the assumption of independence. Even more concerning, because often overlooked, is that structured data also provides ample opportunity for overfitting with non-causal predictors. This problem can persist even if remedies such as autoregressive models, generalized least squares, or mixed models are used. Block cross-validation, where data are split strategically rather than randomly, can address these issues. However, the blocking strategy must be carefully considered. Blocking in space, time, random effects or phylogenetic distance, while accounting for dependencies in the data, may also unwittingly induce extrapolations by restricting the ranges or combinations of predictor variables available for model training, thus overestimating interpolation errors. On the other hand, deliberate blocking in predictor space may also improve error estimates when extrapolation is the modelling goal. Here, we review the ecological literature on non-random and blocked cross-validation approaches. We also provide a series of simulations and case studies, in which we show that, for all instances tested, block cross-validation is nearly universally more appropriate than random cross-validation if the goal is predicting to new data or predictor space, or for selecting causal predictors. We recommend that block cross-validation be used wherever dependence structures exist in a dataset, even if no correlation structure is visible in the fitted model residuals, or if the fitted models account for such correlations.
Donoso, I., Schleuning, M., García, D., Fründ, J.
Defaunation effects on plant recruitment depend on size matching and size trade-offs in seed-dispersal networks
2017 P Roy Soc B-biol Sci, volume: 284, issue: 1855

Abstract Defaunation by humans causes a loss of large animals in many ecosystems globally. Recent work has emphasized the consequences of downsizing in animal communities for ecosystem functioning. However, no study so far has integrated network theory and life-history trade-offs to mechanistically evaluate the functional consequences of defaunation in plant–animal networks. Here, we simulated an avian seed-dispersal network and its derived ecosystem function seedling recruitment to assess the relative importance of different size-related mechanisms. Specifically, we considered size matching (between bird size and seed size) and size trade-offs, which are driven by differences in plant or animal species abundance (negative size– quantity relationship) as well as in recruitment probability and disperser quality (positive size–quality relationship). Defaunation led to impoverished seedling communities in terms of diversity and seed size, but only if models accounted for size matching. In addition, size trade-off in plants, in concert with size matching, provoked rapid decays in seedling abundance in response to defaunation. These results underscore a disproportional importance of large animals for ecosystem functions. Downsizing in ecological networks will have severe consequences for ecosystem functioning, especially in interaction networks that are structured by size matching between plants and animals.
Fornoff, F., Klein, A.-M., Hartig, F., Benadi, G., Venjakob, C., Schaefer, H. M., Ebeling, A.
Functional flower traits and their diversity drive pollinator visitation.
2017 Oikos, volume: 126, issue: 7, pages: 1020 - 1030

Abstract Recent studies have shown that the diversity of flowering plants can enhance pollinator richness and visitation frequency and thereby increase the resilience of pollination. It is assumed that flower traits explain these effects, but it is still unclear which flower traits are responsible, and knowing that, if pollinator richness and visitation frequency are more driven by mass-ratio effects (mean trait values) or by trait diversity. Here, we analyse a three-year data set of pollinator observations collected in a European grassland plant diversity experiment (The Jena experiment). The data entail comprehensive flower trait measurements, including reward traits (nectar and pollen amount), morphological traits (height, symmetry, area, colour spectra), and chemical traits (nectar-amino acid and nectar-sugar concentration). We test if pollinator species richness and visitation frequency of flower communities depend on overall functional diversity combining all flower traits within a community, single trait diversities (within trait variation) and community-weighted means of the single traits, using Bayesian inference. Overall functional diversity did not affect pollinator species richness, but reduced visitation frequency. When looking at individual flower traits separately, we found that single trait diversity of flower reflectance and flower morphology were important predictors of pollinator visitation frequency. Moreover, independent of total flower abundance, community-weighted means of flower height, area, reflectance, nectar-sugar concentration and nectar-amino acid concentration strongly affected both pollinator species richness and visitation frequency. Our results, challenge the idea that functional diversity always positively affects ecosystem functions. Nonetheless, we demonstrate that both single trait diversity and mass-ratio effects of flower traits play an important role for diverse and frequent flower visits, which underlines the functionality of flower traits for pollination services.
Filla, M., Premier, J., Magg, N., Dupke, C., Khorozyan, I., Waltert, M., Bufka, L., Heurich, M.
Habitat selection by Eurasian lynx ('Lynx lynx') is primarily driven by avoidance of human activity during day and prey availability during night
2017 Ecol Evol, volume: 7, pages: 6367 - 6381

Abstract The greatest threat to the protected Eurasian lynx (Lynx lynx) in Central Europe is human-induced mortality. As the availability of lynx prey often peaks in human-modified areas, lynx have to balance successful prey hunting with the risk of encounters with humans. We hypothesized that lynx minimize this risk by adjusting habitat choices to the phases of the day and over seasons. We predicted that (1) due to avoidance of human-dominated areas during daytime, lynx range use is higher at nighttime, that (2) prey availability drives lynx habitat selection at night, whereas high cover, terrain inaccessibility, and distance to human infrastructure drive habitat selection during the day, and that (3) habitat selection also differs between seasons, with altitude being a dominant factor in winter. To test these hypotheses, we analyzed telemetry data (GPS, VHF) of 10 lynx in the Bohemian Forest Ecosystem (Germany, Czech Republic) between 2005 and 2013 using generalized additive mixed models and considering various predictor variables. Night ranges exceeded day ranges by more than 10%. At night, lynx selected open habitats, such as meadows, which are associated with high ungulate abundance. By contrast, during the day, lynx selected habitats offering dense understorey cover and rugged terrain away from human infrastructure. In summer, land-cover type greatly shaped lynx habitats, whereas in winter, lynx selected lower altitudes. We concluded that open habitats need to be considered for more realistic habitat models and contribute to future management and conservation (habitat suitability, carrying capacity) of Eurasian lynx in Central Europe.
Paton, D. G., Ciuti, S., Quinn, M., Boyce, M. S.
Hunting exacerbates the response to human disturbance in large herbivores while migrating through a road network
2017 Ecosphere, volume: 8, issue: 6, page: e01841
Panassiti, B., Hartig, F., Fahrentrapp, J., Breuer, M., Biedermann, R.
Identifying local drivers of a vector-pathogen-disease system using Bayesian modeling
2017 Basic and Applied Ecology, volume: 18, pages: 75 - 85

Abstract ‘Bois noir’ is a phytoplasma-mediated grapevine yellows disease that causes great economic damage in European vineyards. Previous studies have examined habitat relationships on a regional scale, which help to better understand the large-scale epidemiology. Local drivers, such as micro-habitat preferences of the vector (Hyalesthes obsoletus, a cixiid planthopper), or local interactions with reservoir host plants, however, are still poorly understood, although this knowledge is crucial for developing site-specific management strategies. Here, we examined the local environment-species relationships of a phytoplasma-mediated grapevine disease on a scale of 15 m in a 2.9 ha vineyard using: (i) data on elevation and habitat types; (ii) cover of host plants Urtica dioica and Convolvulus arvensis over three seasons, (iii) vector monitoring over four seasons; (iv) genetic tests for phytoplasma presence in the vector; and (v) inspection of 6056 grapevine plants for visual symptoms of the ‘bois noir’ disease. The data were analyzed in a joint causal model that describes the interplay between vector, pathogen, disease and environment, estimated with Bayesian inference. Our results indicate that surrounding natural and semi-natural vegetation (fallow land, forest and managed agricultural land) and high density of the major host plant U. dioica are associated with an increase in vector population densities. Higher vector population densities at low availability of U. dioica were associated with higher phytoplasma infection rates in the vector. The prevalence of disease symptoms in grapevine plants was nonetheless more affected by grapevine cultivar and higher elevation than by the estimated availability of infected vectors. The results of our local analysis support current bois noir management recommendations stating that (1) removal of the host plant U. dioica should be best carried out in either spring or autumn; and (2) grapevine cultivars are unequally susceptible. Moreover, we provide evidence that U. dioica control before the flight period may result in low U. dioica densities and high H. obsoletus population densities, causing an increase in vector infection rates and disease pressure.
El-Gabbas, A., Dormann, C. F.
Improved species-occurrence predictions in data-poor regions: using large-scale data and bias correction with down-weighted Poisson regression and Maxent
2017 Ecography, volume: 41, pages: 1161 - 1172,

Abstract Species distribution modelling (SDM) has become an essential method in ecology and conservation. In the absence of survey data, the majority of SDMs are calibrated with opportunistic presence-only data, incurring substantial sampling bias. We address the challenge of correcting for sampling bias in the data-sparse situations. We modelled the relative intensity of bat records in their entire range using three modelling algorithms under the point-process modelling framework (GLMs with subset selection, GLMs fitted with an elastic-net penalty, and Maxent). To correct for sampling bias, we applied model-based bias correction by incorporating spatial information on site accessibility or sampling efforts. We evaluated the effect of bias correction on the models’ predictive performance (AUC and TSS), calculated on spatial-block cross-validation and a holdout data set. When evaluated with independent, but also sampling-biased test data, correction for sampling bias led to improved predictions. The predictive performance of the three modelling algorithms was very similar. Elastic-net models have intermediate performance, with slight advantage for GLMs on cross-validation and Maxent on hold-out evaluation. Model-based bias correction is very useful in data-sparse situations, where detailed data are not available to apply other bias correction methods. However, bias correction success depends on how well the selected bias variables describe the sources of bias. In this study, accessibility covariates described bias in our data better than the effort covariate, and their use led to larger changes in predictive performance. Objectively evaluating bias correction requires bias-free presence–absence test data, and without them the real improvement for describing a species’ environmental niche cannot be assessed.
Fürstenau Oliveira, J. S., Georgiadis, G., Campello, S., Brandão, R. A., Ciuti, S.
Improving river dolphin monitoring using aerial surveys
2017 Ecosphere
Mupepele, A.-C., Dormann, C. F.
Influence of Forest Harvest on Nitrate Concentration in Temperate Streams—A Meta-Analysis
2017 Forests, volume: 8, issue: 1, page: 5

Abstract Forest harvest alters natural nutrient cycles, which is reflected in stream water run-off from harvested catchments. Nitrate is an essential nutrient for plant growth, but increased concentrations in rivers, lakes, and oceans have contributed to eutrophication and anoxic conditions. Based on a literature review, we assessed the impact of three different harvest methods—clearcut, patchcut, and selective harvest—on nitrate concentrations in temperate forest streams. In a meta-analysis, the influence of harvest methods and additional environmental variables was analysed. Nitrate concentrations are significantly influenced by harvest methods, forest composition, site altitude, and time passed after the harvesting. The remaining unexplained between-site variability is small compared to the between-site variability explained by the model, indicating the model’s validity. The effect of forest harvest is most pronounced in coniferous and deciduous forests, where clearcuts and patchcuts result in high nitrate run-off three to five years after harvest. Mixed forest plots can compensate for clearcut and patchcut, and do not show a significantly increased nitrate concentration after harvest. Selective harvest at low intensities succeeded in maintaining nitrate levels similar to control or pre-harvest levels in coniferous and mixed forests, and showed a positive but not significant trend in deciduous forests. Coniferous and deciduous monocultures clearly face the problem that nitrate wash-out cannot be minimized by reducing clearcut to patchcut harvest, whereas mixed forests are more suitable to diminish nitrate wash-out in both clearcut and patchcut.
Davies, T. E., Maxwell, S. M., Kaschner, K., Garilao, C., Ban, N. C.
Large marine protected areas represent biodiversity now and under climate change
2017 Nature, volume: 7, page: 9569

Abstract Large marine protected areas (>30,000 km2) have a high profile in marine conservation, yet their contribution to conservation is contested. Assessing the overlap of large marine protected areas with 14,172 species, we found large marine protected areas cover 4.4% of the ocean and at least some portion of the range of 83.3% of the species assessed. Of all species within large marine protected areas, 26.9% had at least 10% of their range represented, and this was projected to increase to 40.1% in 2100. Cumulative impacts were significantly higher within large marine protected areas than outside, refuting the critique that they only occur in pristine areas. We recommend future large marine protected areas be sited based on systematic conservation planning practices where possible and include areas beyond national jurisdiction, and provide five key recommendations to improve the long-term representation of all species to meet critical global policy goals (e.g., Convention on Biological Diversity’s Aichi Targets).
Thurfjell, H., Ciuti, S., Boyce, M. S.
Learning from the mistakes of others: how female elk (Cervus elaphus) adjust behaviour with age to avoid hunters
2017 Plos One, volume: 12, issue: 6, page: e0178082
Sarmento Cabral, J., Valente, L., Hartig, F.
Mechanistic simulation models in macroecology and biogeography: state-of-art and prospects
2017 Ecography, volume: 40, issue: 2, pages: 267 - 280

Abstract Macroecology and biogeography are concerned with understanding biodiversity patterns across space and time. In the past, the two disciplines have addressed this question mainly with correlative approaches, despite frequent calls for more mechanistic explanations. Recent advances in computational power, theoretical understanding, and statistical tools are, however, currently facilitating the development of more system-oriented, mechanistic models. We review these models, identify different model types and theoretical frameworks, compare their processes and properties, and summarize emergent findings. We show that ecological (physiology, demographics, dispersal, biotic interactions) and evolutionary processes, as well as environmental and human-induced drivers, are increasingly modelled mechanistically; and that new insights into biodiversity dynamics emerge from these models. Yet, substantial challenges still lie ahead for this young research field. Among these, we identify scaling, calibration, validation, and balancing complexity as pressing issues. Moreover, particular process combinations are still understudied, and so far models tend to be developed for specific applications. Future work should aim at developing more flexible and modular models that not only allow different ecological theories to be expressed and contrasted, but which are also built for tight integration with all macroecological data sources. Moving the field towards such a ‘systems macroecology’ will test and improve our understanding of the causal pathways through which eco-evolutionary processes create diversity patterns across spatial and temporal scales.
Stängle, S. M., Dormann, C. F:
Modelling the variation of bark thickness within and between European silver fir (Abies alba Mill.) trees in southwest Germany
2017 Forestry, volume: 00, pages: 1 - 12

Abstract This study examined bark thickness variability of Silver fir (Abies alba Mill.) in southwest Germany over time and space by comparing a dataset of bark measurements from the 1970s with more recent assessments. Within-tree variability of bark thickness was analysed to estimate the required number of sampling locations per tree for defined accuracy levels. A range of models from the literature that predict bark thickness were compared for their predictive performance and Monte-Carlo simulations were used to estimate the effect of the number of sample trees and plots on the precision of the predictions. In addition, net log volume after bark subtraction was compared for logs of varying lengths to assess the influence of log assortments on calculated sales volume. Results show that several sampling locations are needed per tree and that at least five trees from at least 35 plots should be selected for measurements in the study region. For practical applications, diameter outside bark and breast height diameter are suggested as explanatory variables for models that predict double bark thickness. Additionally, relative tree height and age – and therefore growth rate – significantly improved predictions; however, environmental factors could not explain the variation between stands. Log lengths from 5 to 21m only slightly influenced bark thickness equations that were fit on measurements at log midpoints. The findings highlight the need to consider bark thickness variability at different levels when developing bark thickness equations. In general, bark thickness was found to be smaller in more recent assessments and this indicates the need to regularly review existing bark equations for their validity.
Dormann, C. F., von Riedmatten, L., Scherer-Lorenzen, M.
No consistent effect of plant species richness on resistance to simulated climate change for above- or below-ground processes in managed grasslands
2017 Bmc Ecol, volume: 17, page: 23

Abstract Background: Species richness affects processes and functions in many ecosystems. Since management of temperate grasslands is directly affecting species composition and richness, it can indirectly govern how systems respond to fluctuations in environmental conditions. Our aim in this study was to investigate whether species richness in managed grasslands can buffer the effects of drought and warming manipulations and hence increase the resistance to climate change. We established 45 plots in three regions across Germany, each with three different management regimes (pasture, meadow and mown pasture). We manipulated spring warming using open-top chambers and summer drought using rain-out shelters for 4 weeks. Results: Measurements of species richness, above- and below-ground biomass and soil carbon and nitrogen concentrations showed significant but inconsistent differences among regions, managements and manipulations. We detected a three-way interaction between species richness, management and region, indicating that our study design was sensitive enough to detect even intricate effects. Conclusions: We could not detect a pervasive effect of species richness on biomass differences between treatments and controls, indicating that a combination of spring warming and summer drought effects on grassland systems are not consistently moderated by species richness. We attribute this to the relatively high number of species even at low richness levels, which already provides the complementarity required for positive biodiversity–ecosystem functioning relationships. A review of the literature also indicates that climate manipulations largely fail to show richnessbuffering, while natural experiments do, suggesting that such manipulations are milder than reality or incur treatment artefacts.
Augustynczik, A. L. D., Hartig, F., Minunno, F., Kahle, H.-P., Diaconu, D., Hanewinkel, M., Yousefpour, R.
Productivity of Fagus sylvatica under climate change – A Bayesian analysis of risk and uncertainty using the model 3-PG
2017 Forest Ecol Manag, volume: 401, pages: 192 - 206

Abstract To assess the long-term impacts of forest management interventions under climate change, process- based models, which allow to predict transient dynamics under environmental change, are arguably the most suitable tools available. A challenge for using these models for management decisions, however, is their higher parametric uncertainty, which propagates to predictions and thus into the decision- making process. Here, we demonstrate how this problem can be addressed through Bayesian inference. We first conduct a Bayesian calibration to generate an estimate of posterior parametric uncertainty for the process-based forest growth model 3-PG for Fagus sylvatica. The calibration uses data from twelve sites in Germany, together with a robust (Student’s t) error model. We then propagate the estimated uncertainty together with economic uncertainty to forest productivity and Land Expectation Value (LEV), allowing us to evaluate alternative management regimes under climate change. Our results demonstrate that parametric and economic uncertainty have strong impacts on the variation of predicted forest productivity and profitability. Management regimes with increased thinning intensity were overall most robust to economic, climate change and parametric model uncertainty. We conclude that estimat- ing and propagating economic and model uncertainty is crucial for developing robust adaptive manage- ment strategies for forests under climate change.
Kämmerle, J. L., Coppes, J., Ciuti, S., Suchant, R., Storch, I.
Range loss of a threatened grouse species is related to the relative abundance of a mesopredator
2017 Ecosphere, volume: 8, issue: 9, page: e01934

Abstract Mammalian generalist mesopredators can reach high densities in forest–farmland mosaic landscapes in the absence of top-down control. The abundance of generalist mesopredators is a potentially limiting factor for prey populations, especially ground breeding birds such as grouse. High mesopredator abundance has been associated with reduced reproductive success in grouse. There is little evidence, however, on how variation in mesopredator abundance affects grouse population trends while considering other environmental covariates. We make use of range maps spanning two decades (1993–2013) of a locally threatened capercaillie (Tetrao urogallus) population in the Black Forest, Germany, to assess whether range loss of grouse in forest–farmland mosaic landscapes can be explained by a gradient in red fox abundance, while accounting for other potential determinants of grouse range loss. We show that capercaillie range persistence was favored by increasing snow cover, decreasing index of red fox abundance, slightly increasing index for soil quality, and increasing population connectivity. Red fox abundance had the largest relative impact in areas already facing an elevated capercaillie extinction risk due to unsuitable site conditions, dense forests, or lack of connectivity, but the negative effect was compensated under otherwise optimal conditions. This indicates that the relative importance of predator abundance for prey population dynamics is mediated by environmental attributes, emphasizing the threat to remnant populations but also indicating potential for species conservation.
de Avila, A. L., Schwartz, G., Ruschel, A. R., Lopes, J. C., Macedo Silva, J. N., Pereira de Carvalho, J. O., Dormann, C. F., Mazzei, L., Mota Soares, M. H., Bauhus, J.
Recruitment, growth and recovery of commercial tree species over 30 years following logging and thinning in a tropical rain forest
2017 Forest Ecol Manag, volume: 385, pages: 225 - 235

Abstract Sustainable production of timber from commercial species across felling cycles is a core challenge for tropical silviculture. In this study, we analysed how the intensity and type (harvesting and thinning) of silvicultural interventions affect: (a) recruitment of small stems (5 cm 6 DBH < 15 cm), (b) increment of future crop trees (15 cm 6 DBH < 50 cm) and (c) recovery of harvestable growing stocks (DBHP50 cm) of 52 commercial timber species in the Tapajós National Forest, Brazil. Intervention intensities comprised logging (on average 61 m3 ha!1) and associated damage to remaining trees (1982) and thinning (refinement) to reduce basal area at the stand level (1993/1994). These interventions together resulted in a gradient of reduction in basal-area from 19 to 53% relative to pre-logging stocks. Trees (DBHP5 cm) were measured on eight occasions in 41 permanent sample plots of 0.25 ha each. The dynamics were analysed at the stand level over 30 years and compared among treatments (including unlogged forest) and to pre-logging stands. Recruitment and growth temporarily increased following interventions and recovery of harvestable growing stock decreased with intervention intensity. Harvesting substantially increased recruitment of small stems relative to the unlogged forest, but recruitment rates decreased over time and did not increase following thinning. Gross increment of future crop trees was higher in logged than in unlogged forest and increased over time with high intensity of followup thinning, where it remained significantly higher than in control plots over time. Increased recruitment rates and volume increments were mainly driven by long-lived pioneer species, changing the composition of the growing stock. In 2012, recovery of harvestable growing stock of the 22 species harvested in 1982 varied between 19% and 57% in logged treatments relative to pre-logging levels. When considering an additional group of 30 species that were not harvested in the permanent sample plots but are now potentially commercial, relative recovery increased enough to support a second harvest under the present regulations (maximum harvest of 30 m3 ha!1), except for treatment with high thinning intensity where stocks were still less than 30% relative to pre-harvest levels. In contrast, light and medium thinning intensity promoted recovery of harvestable growing stock. These findings indicate that intensive thinning should be avoided and silvicultural interventions oriented towards future crop trees of target species should be adopted. This may enhance recovery and reduce unintended changes in composition of the commercial growing stock.
Batáry, P., Gallé, R., Riesch, F., Fischer, C., Dormann, C. F., Mußhof, O., Császár, P., Fusaro, S., Gayer, C., Happe, A.-K., Kurucz, K., Molnár, D., Rösch, V., Wietzke, A., Tscharntke, T.
The former Iron Curtain still drives biodiversity– profit trade-offs in German agriculture
2017 Ecol Evol, volume: 1, pages: 1279 - 1284

Abstract Agricultural intensification drives biodiversity loss and shapes farmers’ profit, but the role of legacy effects and detailed quan- tification of ecological–economic trade-offs are largely unknown. In Europe during the 1950s, the Eastern communist bloc switched to large-scale farming by forced collectivization of small farms, while the West kept small-scale private farming. Here we show that large-scale agriculture in East Germany reduced biodiversity, which has been maintained in West Germany due to >70% longer field edges than those in the East. In contrast, profit per farmland area in the East was 50% higher than that in the West, despite similar yield levels. In both regions, switching from conventional to organic farming increased biodiversity and halved yield levels, but doubled farmers’ profits. In conclusion, European Union policy should acknowledge the surprisingly high biodiversity benefits of small-scale agriculture, which are on a par with conversion to organic agriculture.
Schwarz, B.,, Barnes, A.,, Thakur, M.,, Brose, U.,, Ciobanu, M.,, Reich, P.,, Rich, R.,, Rosenbaum, B.,, Stefanski, A.,, Eisenhauer, N.
Warming alters energetic structure and function but not resilience of soil food webs
2017 Nat Clim Change, volume: 7, pages: 895 - 900

Abstract Climate warming is predicted to alter the structure, stability, and functioning of food webs1,2,3,4,5. Yet, despite the importance of soil food webs for energy and nutrient turnover in terrestrial ecosystems, the effects of warming on these food webs—particularly in combination with other global change drivers—are largely unknown. Here, we present results from two complementary field experiments that test the interactive effects of warming with forest canopy disturbance and drought on energy flux in boreal–temperate ecotonal forest soil food webs. The first experiment applied a simultaneous above- and belowground warming treatment (ambient, +1.7 °C, +3.4 °C) to closed-canopy and recently clear-cut forest, simulating common forest disturbance6. The second experiment crossed warming with a summer drought treatment (−40% rainfall) in the clear-cut habitats. We show that warming reduces energy flux to microbes, while forest canopy disturbance and drought facilitates warming-induced increases in energy flux to higher trophic levels and exacerbates the reduction in energy flux to microbes, respectively. Contrary to expectations, we find no change in whole-network resilience to perturbations, but significant losses in ecosystem functioning. Warming thus interacts with forest disturbance and drought, shaping the energetic structure of soil food webs and threatening the provisioning of multiple ecosystem functions in boreal–temperate ecotonal forests.
Avila, I.C., Correa, L. M., Van Waerebeek, K.
Where humpback whales and vessel traffic coincide, a Colombian Pacific case study.
2017 Boletin del Museo Nacional de Historia Natural, Chile, volume: 66, pages: 85 - 99

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2016

Fasiolo, M., Wood, S.N., Hartig, F., Bravington, M.V.
An Extended Empirical Saddlepoint Approximation for Intractable Likelihoods
2016 arXiv

Abstract The challenges posed by complex stochastic models used in fields such as computational ecology, biology and genetics have stimulated the development of approximate approaches to statistical inference. Here we focus on Synthetic Likelihood, a procedure that reduces the observed and simulated data to a set of summary statistics, and quantifies the discrepancy between them through a synthetic likelihood function. Synthetic Likelihood requires little tuning, but it relies on the approximate normality of the summary statistics. We relax this assumption by proposing a novel flexible density estimator: the Extended Empirical Saddlepoint approximation1 . We illustrate the method using a simple example, and a complex individual-based forest model for which synthetic likelihood offers one of the few practical possibilities for statistical inference. The examples show that the new density estimator is able to capture large departures from normality, while being scalable to high dimensions, which leads to more accurate parameter estimates, relative to the Gaussian alternative

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Mupepele, A.-C., Walsh, J. C., Sutherland, W. J., Dormann, C. F.
An evidence assessment tool for ecosystem services and conservation studies
2016 Ecol Appl, volume: 26, issue: 5, pages: 1295 - 1301

Abstract Reliability of scientific findings is important, especially if they directly impact decision making, such as in environmental management. In the 1990s, assessments of reliability in the medical field resulted in the development of evidence-based practice. Ten years later, evidence-based practice was translated into conservation, but so far no guidelines exist on how to assess the evidence of individual studies. Assessing the evidence of individual studies is essential to appropriately identify and summarize the confidence in research findings. We develop a tool to assess the strength of evidence of ecosystem services and conservation studies. This tool consists of (1) a hierarchy of evidence, based on the experimental design of studies and (2) a critical-appraisal checklist that identifies the quality of research implementation. The application is illustrated with 13 examples and we suggest further steps required to move towards more evidence-based environmental management.
Berberich, G., Grumpe, A., Berberich, M., Klimetzek, D., Wöhler, C.
Are red wood ants ('Formica rufa' - group) tectonic indicators? A statistical approach
2016 Ecol Indic, volume: 61, pages: 968 - 979

Abstract Recent research in seismically active areas indicated that the spatial distributions of geochemical soil gas anomalies and nests of red wood ants (RWA; Formica rufa-group) are strongly correlated. Here we applied a modified Hough Transform (mHT) and an Iterative Mode Detection (IMD) to RWA nest positions, which we mapped in two Southwest German study areas (Black Forest and Bodanrück), to test for statistical significance of correlation with tectonic features. RWA densities in the seismically active study areas reaching up to 1600 nests/100 ha are about 100× higher than overall values for Northern and Southern Germany. Since the shape of edges of the study area was found to strongly influence the selection of distribution patterns, all subsequent analyses were carried out for circular study areas. Results of the mHT applied on the RWA nests in both study areas clearly showed several modes which correspond to preferred directions. Centres of the modes further processed by IMD transferred into a GIS as RWA prototype lines showed very dominant directions of RWA nest distributions in right lateral strike-slip mode in WNW-ESE resp. NW-SE direction but also in extension direction caused by the recent main stress field in NW-SE resp. NNW-SSE direction. It could thus be clearly shown that the large scale spatial distribution of RWA nests directly reflects significant components of the present day stress field and its accompanying conjugated shear systems: Linear alignments of RWA nests indicate the course of active degassing faults zones and nest clusters indicate area-wide geochemical anomalies respectively crosscut zones of different fault systems. Furthermore, directions of re-activated shear systems, e.g. from Eocene-Oligocene but also from Late Jurassic that had been modified by overprinting due to changes of the main stress field could be identified. Therefore, RWA prototype lines complement and clarify the shear sense and the tectonic regime identified in previous tectonic studies. The high degree of statistical significance of these results will also allow a rating with former contrasting interpretations as to the drivers of RWA distributions.
Singer, A., Johst, K., Banitz, T., Fowler, M. S., Groeneveld, J., Gutiérrez, A.G., Hartig, F., Krug, R.M., Liess, M., Matlack, G., Meyer, K.M., Pe’er, G., Radchuka, V., Voinopol-Sassu, A.-J., Travi, J.M.J.
Community dynamics under environmental change: How can next generation mechanistic models improve projections of species distributions?
2016 Ecol Model, volume: 326, pages: 63 - 74

Abstract Environmental change is expected to shift the geographic range of species and communities. To estimate the consequences of these shifts for the functioning and stability of ecosystems, reliable predictions of alterations in species distributions are needed. Projections with correlative species distribution models, which correlate species’ distributions to the abiotic environment, have become a standard approach. Criticism of this approach centres around the omission of relevant biotic feedbacks and triggered the search for alternatives. A new generation of mechanistic process-based species distribution models aims at implementing formulations of relevant biotic processes to cover species’ life histories, physiology, dispersal abilities, evolution, and both intra- and interspecific interactions. Although this step towards more structural realism is considered important, it remains unclear whether the resulting projections are more reliable. Structural realism has the advantage that geographic range shifting emerges from the interplay of relevant abiotic and biotic processes. Having implemented the relevant response mechanisms, structural realistic models should better tackle the challenge of generating projections of species responses to (non-analogous) environmental change. However, reliable projections of future species ranges demand ecological information that is currently only available for few species. In this opinion paper, we discuss how the discrepancy between demand for structural realism on the one hand and the related knowledge gaps on the other hand affects the reliability of mechanistic species distribution models. We argue that omission of relevant processes potentially impairs projection accuracy (proximity of the mean outcome to the true value), particularly if species range shifts emerge from species and community dynamics. Yet, insuf- ficient knowledge that limits model specification and parameterization, as well as process complexity,
Hauenstein, S., Wood, S. N., Dormann, C. F.
Computing AIC for black-box models using Generalised Degrees of Freedom: a comparison with cross-validation
2016 Commun Stat-simul C, volume: 47, pages: 1382 - 1396

Abstract Generalised Degrees of Freedom (GDF), as defined by Ye (1998 JASA 93:120-131), represent the sensitivity of model fits to perturbations of the data. As such they can be computed for any statistical model, making it possible, in principle, to derive the number of parameters in machine-learning approaches. Defined originally for normally distributed data only, we here investigate the potential of this approach for Bernoulli-data. GDF-values for models of simulated and real data are compared to model complexity-estimates from cross-validation. Similarly, we computed GDF-based AICc for randomForest, neural networks and boosted regression trees and demonstrated its similarity to cross-validation. GDF-estimates for binary data were unstable and inconsistently sensitive to the number of data points perturbed simultaneously, while at the same time being extremely computer-intensive in their calculation. Repeated 10-fold cross-validation was more robust, based on fewer assumptions and faster to compute. Our findings suggest that the GDF-approach does not readily transfer to Bernoulli data and a wider range of regression approaches
El-Gabbas, A., Baha El Din, S., Zalat, S., Gilbert, S.
Conserving Egypt’s reptiles under climate change.
2016 J Arid Environ, volume: 127, pages: 211 - 221

Abstract Climate change has caused range shifts and extinctions of many species in the recent past. In this study, the effects of climate change on Egyptian reptiles were investigated for the first time using species distribution models. Maxent was used to model the current and future distributions of suitable habitats for 75 terrestrial reptile species from Egypt. The modelled distribution for current suitable conditions for each species was projected into the future at three time slices using two emission scenarios from four global circulation models and under two assumptions of dispersal ability. Climate change is expected to vary in its effects spatially, with some areas characterized by increased species richness while others show declines. Future range changes vary among species and different future projections, from the entire loss to large gains in range. Two species were expected to become extinct in at least one future projection, and eight species were expected to lose >80% of their current distribution. Although Protected Areas have greater conservation value, on average, compared to unprotected areas, they appear inadequate to conserve Egyptian reptiles under expected climate change.
Berberich, G. M., Dormann, C. F., Klimetzek, D., Berberich, M. B., Sanders, N. J., Ellison, A. M.
Detection probabilities for sessile organisms
2016 Ecosphere, volume: 7, issue: 11, page: e01546

Abstract Estimation of population sizes and species ranges is central to population and conservation biology. It is widely appreciated that imperfect detection of mobile animals must be accounted for when estimating population size from presence–absence data. Sessile organisms also are imperfectly detected, but correction for detection probability in estimating their population sizes is rare. We illustrate challenges of detection probability and population estimation of sessile organisms using censuses of red wood ant (Formica rufa- group) nests as a case study. These ants, widespread in the northern hemisphere, can make large (up to 2 m tall), highly visible nests. Using data from a mapping campaign by eight observers with varying experience of sixteen 3600- m2 plots in the Black Forest region of southwest Germany, we compared three different statistical approaches (a nest- level data- augmentation patch- occupancy model with event- specific covariates; a plot- level Bayesian and maximum- likelihood model; nonparametric Chao- type estimators) for quantifying detection probability of sessile organisms. Detection probabilities by individual observers of red wood ant nests ranged from 0.31 to 0.64 for small nests, depending on observer experience and nest size (detection rates were approximately 0.17 higher for large nests), but not on habitat characteristics (forest type, local vegetation). Robust estimation of population density of sessile organisms—even highly apparent ones such as red wood ant nests—thus requires estimation of detection probability, just as it does when estimating population density of rare or cryptic species. Our models additionally provide approaches to calculate the number of observers needed for a required level of accuracy. Estimating detection probability is vital not only when censuses are conducted by experts, but also when citizen- scientists are engaged in mapping and monitoring of both common and rare species.
Benz, R. A., Boyce, M. S., Thurfjell, H., Paton, D. G., Musiani, M., Dormann, C. F., Ciuti, S.
Dispersal Ecology Informs Design of Large-Scale Wildlife Corridors.
2016 Plos One, volume: 11, issue: 9, page: e0162989

Abstract Landscape connectivity describes how the movement of animals relates to landscape structure. The way in which movement among populations is affected by environmental conditions is important for predicting the effects of habitat fragmentation, and for defining conservation corridors. One approach has been to map resistance surfaces to characterize how environmental variables affect animal movement, and to use these surfaces to model connectivity. However, current connectivity modelling typically uses information on species location or habitat preference rather than movement, which unfortunately may not capture dispersal limitations. Here we emphasize the importance of implementing dispersal ecology into landscape connectivity, i.e., observing patterns of habitat selection by dispersers during different phases of new areas’ colonization to infer habitat connectivity. Disperser animals undertake a complex sequence of movements concatenated over time and strictly dependent on species ecology. Using satellite telemetry, we investigated the movement ecology of 54 young male elk Cervus elaphus, which commonly disperse, to design a corridor network across the Northern Rocky Mountains. Winter residency period is often followed by a spring-summer movement phase, when young elk migrate with mothers’ groups to summering areas, and by a further dispersal bout performed alone to a novel summer area. After another summer residency phase, dispersers usually undertake a final autumnal movement to reach novel wintering areas. We used resource selection functions to identify winter and summer habitats selected by elk during residency phases. We then extracted movements undertaken during spring to move from winter to summer areas, and during autumn to move from summer to winter areas, and modelled them using step selection functions. We built friction surfaces, merged the different movement phases, and eventually mapped least-cost corridors. We showed an application of this tool by creating a scenario with movement predicted as there were no roads, and mapping highways’ segments impeding elk connectivity.
Schleuning, M., Fründ, J., Schweiger, O., Welk, E., Albrecht, J., Albrecht, M., Beil, M., Benadi, G., Blüthgen, N., Bruelheide, H., Böhning-Gaese, K., Dehling, D. M., Dormann, C. F., Exeler, N., Farwig, N., Harpke, A., Hickler, T., Kratochwil, A., Kuhlmann, M., Kühn, I., Michez, D., Mudri-Stojnić, S., Plein, M., Rasmont, P., Schwabe, A., Settele, J., Vujić, A., Weiner, C. N., Wiemers, M., Hof, C.
Ecological networks are more sensitive to plantthan to animal extinction under climate change
2016 Nat Commun, page: online

Abstract Impacts of climate change on individual species are increasingly well documented, but welack understanding of how these effects propagate through ecological communities. Here wecombine species distribution models with ecological network analyses to test potentialimpacts of climate change on 4700 plant and animal species in pollination and seed-dispersal networks from central Europe. We discover that animal species that interact with alow diversity of plant species have narrow climatic niches and are most vulnerable to climatechange. In contrast, biotic specialization of plants is not related to climatic niche breadth andvulnerability. A simulation model incorporating different scenarios of species coextinction andcapacities for partner switches shows that projected plant extinctions under climate changeare more likely to trigger animal coextinctions than vice versa. This result demonstrates thatimpacts of climate change on biodiversity can be ampliﬁed via extinction cascades fromplants to animals in ecological networks
Brieger, F., Hagen, R., Vetter, D., Dormann, C. F., Storch, I.
Effectiveness of light-reflecting devices: A systematic reanalysis of animal-vehicle collision data
2016 Accident Anal Prev, volume: 97, pages: 242 - 260

Abstract Every year, approximately 500 human fatalities occur due to animal-vehicle collisions in the United States and Europe. Especially heavy-bodied animals affect road safety. For more than 50 years, light-reflecting devices such as wildlife warning reflectors have been employed to alert animals to traffic when crossing roads during twilight and night. Numerous studies addressed the effectiveness of light-reflecting devices in reducing collisions with animals in past decades, but yielded contradictory results. In this study, we conducted a systematic literature review to investigate whether light-reflecting devices contribute to an effective prevention of animal-vehicle collisions. We reviewed 53 references and reanalyzed original data of animal-vehicle collisions with meta-analytical methods. We calculated an effect size based on the annual number of animal-vehicle collisions per kilometer of road to compare segments with and without the installation of light-reflecting devices for 185 roads in Europe and North America. Our results indicate that light-reflecting devices did not significantly reduce the number of animal-vehicle collisions. However, we observed considerable differences of effect sizes with respect to study duration, study design, and country. Our results suggest that length of the road segment studied, study duration, study design and public attitude (preconception) to the functioning of devices may affect whether the documented number of animal-vehicle collisions in- or decrease and might in turn influence whether results obtained were published.
Mupepele, A.-C., Dormann C. F.
Environmental management: Synthesize evidence to steer decisions
2016 Nature, volume: 529, pages: 466 - 466

Abstract Using evidence mapping to display and categorize environmental studies cannot replace 'evidence synthesis' in guiding decision-making (M. C. McKinnon et al. Nature 528, 185–187; 2015). There are no shortcuts to evidence-based practice. The results of investigations need to be synthesized to allow conclusions to be drawn from contradicting data (L. V. Dicks et al. Trends Ecol. Evol. 29, 607–613; 2014). Studies can be assigned a 'level of evidence' indicator of design and quality, which is derived from evidence hierarchies (see, for example, A.-C. Mupepele et al. Ecol. Appl. http://dx.doi.org/10.1890/15-0595.1; 2016). This indicator reflects the confidence with which the reported outcome can be causally attributed to the investigated driver. Practitioners' questions are rarely answered directly by an existing set of studies. Evidence-based medicine tackles this problem by developing clinical guidelines on the basis of collated scientific results and clinical experience, and by using systematic reviews of research results and evidence assessments that are supported by hierarchies.
Boch, S., Allan, E., Birkhofer, K., Bossdorf, O., Blüthgen, N., Christ-Breulmann, S., Diekötter, T., Dormann, C. F., Gossner, M. M., Hallmann, C., Hemp, A., Hölzel, N., Jung, K., Klaus, V. H., Klein, A. M., Kleinebecker, T., Lange, M., Müller, J., Nacke, H., Prati, D., Renner, S. C., Rothenwöhrer, C., Schall, P., Schulze, E.-D., Socher, S. A., Tscharntke, T., Türke, M., Weiner, C. N., Weisser, W. W., Westphal, C., Wolters, V., Wubet, T., Fischer, M.
Extensive und jährlich wechselnde Nutzungsintensität fördert den Artenreichtum im Grünland
2016 ANLiegen Natur, volume: 38, issue: 1, pages: online 10 - S.

Abstract Among the processes currently eroding biodiversity, land-use intensification is one of the most important. Using data from 150 grasslands, in three regions of Germany, we therefore tested for effects of land-use intensity and inter-annual variation in land-use intensity on biodiversity. To measure whole ecosystem biodiversity, we introduce a new metric of multidiversity, which incorporates the diversities of up to 49 taxonomic groups of plants, animals, fungi and bacteria. Multidiversity declined with increasing land-use intensity, particularly for rarer species and aboveground groups, while common species and belowground species were less sensitive. However, high levels of inter-annual variation in land-use intensity increased overall multidiversity and slowed the rate at which the multidiversity of rarer species declined with increasing land-use intensity. In addition to decreasing mean land-use intensity, we suggest that varying land-use intensity across years, in particular varying grazing intensity over time, could be a novel strategy to reduce local biodiversity loss.
Berberich, G. M., Sattler, T., Klimetzek, D., Benk, S. A., Berberich, M. B., Polag, D., Schöler, H. F., Atlas, E.
Halogenation processes linked to red wood ant nests ('Formica spp.') and tectonics.
2016 J Atmos Chem, pages: 1 - 21

Abstract We investigated and evaluated the occurrence of fault zone tracer gases (CO2, He, Rn), volatile organohalogens (CH3Cl, CHCl3, CHBr3), alkanes and limonene in soil and nest gases of red wood ants (RWA) in comparison to ambient air, in a seismically active area. In this new approach, we compared RWA-free areas to RWA-areas by combining different investigation and analytical methods. In soil gas, the fault zone tracer gas Rn was surprisingly highly correlated to limonene, suggesting a combination of biotic production of limonene and abiotic degassing of Rn in a seismically active area; moderate correlations were found with trihalomethanes and other halocarbons. In RWA nests a variety of elevated concentrations of haloforms were found, while remaining below the atmospheric background values in RWA-free areas. The evidence of CHCl3 in RWA nests is the first record. Its average concentrations in nests of F. rufa and F. polyctena were up to 3 fold higher than atmospheric background and up to 28–70 fold higher compared to e.g. volcanic emissions being considered as one of its main geogenic sources. Thus, RWA nests could possibly be an additional source for CHCl3 liberation. Consequently, apart from RWA being bioindicators for seismically active degassing faults, they might also be used as bioindicators for CHCl3 formation in forest soils. Although we cannot yet differentiate between a geogenic/abiotic and a biotic formation. RWA nests will have to be reconsidered for halocarbon formation in future quantifications of geochemical cycles at global scale, since they impact organic soil chemistry through biotic and/or abiotic pathways. Therefore, further larger-scale research in different tectonic settings but also in well-known CHCl3 “hot spot” study areas such as the Klosterhede area (Denmark) should focus directly on gas sampling from confirmed active fault systems. Nests of other ant species should be addressed to compare seasonal, diurnal and nocturnal variations of degassing procedures in relation to earth tides, different geologic settings, and tectonic events such as earthquakes and on quantifying the fluxes to the atmosphere.
Sohn, J. A., Hartig, F., Kohler, M., Huss, J., Bauhus, J.
Heavy and frequent thinning promotes drought adaptation in 'Pinus sylvestris' forests
2016 Ecol Appl

Abstract Droughts and their negative effects on forest ecosystems are projected to increase under climate change for many regions. It has been suggested that intensive thinning could reduce drought impacts on established forests in the short-term. Most previous studies on the effect of thinning on drought impacts, however, have been confined to single forest sites. It is therefore still unclear how general and persisting the benefits of thinning are. This study assesses the potential of thinning to increase drought tolerance of the wide spread Scots pine (Pinus sylvestris) in Central Europe. We hypothesized 1) that increasing thinning intensity benefits the maintenance of radial growth of crop trees during drought (resistance) and its recovery following drought, 2) that those benefits to growth decrease with time elapsed since the last thinning and with stand age, and 3) that they may depend on drought severity as well as water limitations in pre- and post-drought periods. To test these hypotheses, we assessed the effects of thinning regime, stand age, and drought severity on radial growth of 129 Scots pine trees during and after drought events in 4 long-term thinning experiments in Germany. We find that thinning improved the recovery of radial growth following drought and to a lesser extent the growth resistance during a drought event. Growth recovery following drought was highest after the first thinning intervention and in recently and heavily thinned stands. With time since the last thinning, however, this effect decreased and could even become negative when compared to unthinned stands. Further, thinning helped to avoid an age-related decline in growth resistance (and recovery) following drought. The recovery following drought, but not the resistance during drought, was related to water limitations in the drought period. This is the first study that analyzed drought-related radial growth in trees of one species across several stands of different age. The interaction between thinning intensity and time since the last thinning underline the importance to distinguish between short- and long-term effects of thinning. According to our analysis, only thinning regimes, with relatively heavy and frequent thinning interventions would increase drought tolerance in pine stands.
Stängle, S. M., Weiskittel, A. R., Dormann, C. F., Brüchert, F.
Measurement and prediction of bark thickness in Picea abies: assessment of accuracy, precision, and sample size requirements
2016 Can J Forest Res, volume: 46, pages: 39 - 47

Abstract Tree and log diameters are usually measured outside bark, but inside-bark diameters are of greater economic interest and are often derived with local or regional bark thickness equations. To date, the influence of measurement method, sampling design, and sample size on bark thickness equation accuracy and precision has received limited attention. The objectives of this study were to use an extensive regional bark thickness dataset for Norway spruce (Picea abies (L.) Karst) in southwestern Germany to (1) quantify the accuracy and precision of bark thickness measurements with a Swedish bark gauge, (2) determine the required number of measurements to assess the within-tree variation, and (3) estimate the required sample sizes per plot and per region to develop an accurate bark thickness prediction equation. Bark gauge readings were validated with measurements derived from X-ray computed tomography (CT) and indicate that Swedish bark gauges generally overestimated bark thickness by 13.6% ± 28.4% (mean ± standard deviation). Results suggested having at least one measurement location every 2malong a tree bole and at least five bark thickness measurements per each of these locations to achieve an allowable error of <15%. For the study area, Monte Carlo simulations indicated that a total sample size of 50–250 trees was needed, depending on the complexity of the desired bark thickness model. Overall, this analysis indicated that there was relatively high within- and between-tree variation
Ciuti, S., Apollonio, M.
Reproductive timing in a lekking mammal: male fallow deer getting ready for female estrus
2016 Behav Ecol

Abstract A lek is an aggregated male display that females attend for the purpose of fertilization. A male needs to climb the relative hierarchy to be available for mating when the peak of female estrus occurs. We analyzed the link between timing of lek use by males in relation to age, phenotype, territoriality, and mating success. For more than a decade, we collected radio-tracking data and behavioral observations of a lekking mammal, the fallow deer (Dama dama). Competitively stronger males (i.e., older and heavier males with larger antlers) moved to the lek before less competitive ones. However, an early arrival did not guarantee the territory defense for a longer period nor higher mating success. The early arrival seemed to be a necessary but not sufficient condition to be a successful male in a lek. In fact, the ability to defend a territory for longer was related to age, body mass, antler length but not arrival time. We accordingly argue that males move to the lek early because they need to engage in male–male interactions and scent-marking activities. Successful males left the lek later than unsuccessful ones. The latter did not attempt to compensate for their low mating success by remaining in the lek, likely adopting alternative strategies outside of it. Adult males seeking for a chance to defend the territory and mate have to move to the lek early and stay there until the end of the rut, though this does not guarantee them a higher mating success.
El-Gabbas, A., Gilbert, F.
The Desert Beauty 'Calopieris eulimene': a butterfly new to Egypt (Insecta: Lepidoptera)
2016 Zool Middle East

Abstract The butterfly genus Calopieris Aurivillius, 1898 has only one species: the Desert Beauty Calopieris eulimene (Klug, 1829) (Ackery, Smith, & Vane-Wright, 1985), which is a rare Afrotropical species considered to be one of the most xerophilic butterflies in Africa (T. Larsen, pers. comm.; Williams, 2015). It is endemic to the Somali sub-region (Nazari et al., 2011), having been recorded only from Sudan, Yemen, western Saudi Arabia (20 km south of Mecca), Chad, Eritrea, and Ethiopia (T. Larsen, pers. comm.; Ackery et al., 1985; Gabriel, 1949; Larsen, 1982; Williams, 2015). The type specimens come from Ambukol, Dongola district, Sudan (Longstaff, 1913). The distribution is shown in Figure 1. Most of the available records are from between 1828 and 1980, with only one relatively recent record in 2007 from South of Jebel Aulla, Sudan (Williams, 2015). It is a poorly known butterfly with relatively few records and hardly any information on its biology and ecology (T. Larsen, pers. comm.; but see Waterfield, 1925). The larvae turn up on the leafless bushes of the Desert Caper Capparis decidua (Capparaceae), and adults are mostly associated with it (Ackery et al., 1985; Longstaff, 1913): it does not seem to visit the flowers of other plants (Waterfield, 1925). Many (20-30) individuals of C. eulimene were recorded on 29 May 2011 and 29 November 2012 in a small wadi named ‘Srob Kwan’ in the Meisah area of the Gebel Elba Protected Area (22.319°N, 35.603°E; 451 m a.s.l.) in southeastern Egypt (Figure 2). The adults were found hovering over the Desert Caper (Capparis decidua; local name: Tundob), confirming previous observations (e.g. Ackery et al., 1985). The surrounding wadis were roughly surveyed on the same days, but no other populations of C. eulimene were observed. Other recorded butterfly species included Danaus chrysippus, Pontia glauconome, Colotis danae, C. chrysonome, and C. liagore. Based on the two most recent comprehensive studies on the Egyptian butterflies, there are 61 butterfly species recorded from Egypt (Gilbert & Zalat, 2007; Larsen, 1990). C. eulimene has not been reported from Egypt before, although Larsen (1990) expected its distribution to extend to the extreme south of Egypt. The Desert Caper is widespread in Egypt, inhabiting desert wadis and sandy alluvial plains. It is found in various phytogeographical regions in Egypt, including the Nile region, oases, desert areas, the Red Sea coastal strip, Sinai, and Gebel Elba (Boulos, 1999). In Gebel Elba Protected Area, it has been recorded from many locations (for details: Al-Gohary, 2009). It has also been recorded from other locations in southernEgypt, including Wadi El Gemal and Wadi El Allaqi Protected Areas (Mahmoud & Gairola, 2013; Springuel, Sheded, & Murphy, 1997). The presence of the Desert Caper at different locations in southern Egypt may support the existence of C. eulimene populations at other places in southern Egypt, especially since such places are often remote areas that receive very low sampling effort: sampling is commonly biased towards areas close to main cities or roads. Given that C. eulimene has been recorded so far only from a very small region in Egypt, it gives the Gebel Elba Protected Area high responsibility to conserve this species and its habitat, and other nearby Protected Areas (Wadi El Allaqi, Wadi El Gemal) should be thoroughly explored to show more accurately its distribution within Egypt.
Watts, S., Dormann, C. F., Martín González, A. M., Ollerton, J.
The influence of floral traits on specialization and modularity of plant–pollinator networks in a biodiversity hotspot in the Peruvian Andes
2016 Annals of Botany, volume: 118, pages: 415 - 429

Abstract ! Background and Aims Modularity is a ubiquitous and important structural property of ecological networks which describes the relative strengths of sets of interacting species and gives insights into the dynamics of ecological communities. However, this has rarely been studied in species-rich, tropical plant–pollinator networks. Working in a biodiversity hotspot in the Peruvian Andes we assessed the structure of quantitative plant–pollinator networks in nine valleys, quantifying modularity among networks, defining the topological roles of species and the influence of floral traits on specialization. ! Methods A total of 90 transects were surveyed for plants and pollinators at different altitudes and across different life zones. Quantitative modularity (QuanBiMo) was used to detect modularity and six indices were used to quantify specialization. ! Key Results All networks were highly structured, moderately specialized and significantly modular regardless of size. The strongest hubs were Baccharis plants, Apis mellifera, Bombus funebris and Diptera spp., which were the most ubiquitous and abundant species with the longest phenologies. Species strength showed a strong association with the modular structure of plant–pollinator networks. Hubs and connectors were the most centralized participants in the networks and were ranked highest (high generalization) when quantifying specialization with most indices. However, complementary specialization d’ quantified hubs and connectors as moderately specialized. Specialization and topological roles of species were remarkably constant across some sites, but highly variable in others. Networks were dominated by ecologically and functionally generalist plant species with open access flowers which are closely related taxonomically with similar morphology and rewards. Plants associated with hummingbirds had the highest level of complementary specialization and exclusivity in modules (functional specialists) and the longest corollas. ! Conclusions We have demonstrated that the topology of networks in this tropical montane environment was non-random and highly organized. Our findings underline that specialization indices convey different concepts of specialization and hence quantify different aspects, and that measuring specialization requires careful consideration of what defines a specialist.

2015

Coro, G., Magliozzi, C., Ellenbroek, A., Kaschner, K., Pagano, P.
Automatic classification of climate change effects on marine species distributions in 2050 using the AquaMaps model
2015 Environ Ecol Stat, pages: 1 - 26

Abstract Habitat modifications driven by human impact and climate change may influence species distribution, particularly in aquatic environments. Niche-based models are commonly used to evaluate the availability and suitability of habitat and assess the consequences of future climate scenarios on a species range and shifting edges of its distribution. Together with knowledge on biology and ecology, niche models also allow evaluating the potential of species to react to expected changes. The availability of projections of future climate scenarios allows comparing current and future niche distributions, assessing a species’ habitat suitability modification and shift, and consequently estimating potential species’ reaction. In this study, differences between the distribution maps of 406 marine species, which were produced by the AquaMaps niche models on current and future (year 2050) scenarios, were estimated and evaluated. Discrepancy measurements were used to identify a discrete number of categories, which represent different responses to climate change. Clustering analysis was then used to automatically detect these categories, demonstrating their reliability compared to human supervised classification. Finally, the distribution of characteristics like extinction risk (based on IUCN categories), taxonomic groups, population trends and habitat suitability change over the clustering categories was evaluated. In this assessment, direct human impact was neglected, in order to focus only on the consequences of environmental changes. Furthermore, in the comparison between two climate snapshots, the intermediate phases were assumed to be implicitly included into the model of the 2050 climate scenario.
Panassiti, B., Hartig, F., Breuer, M., Biedermann, R.
Bayesian inference of environmental and biotic factors determining the occurrence of the grapevine disease ‘bois noir'
2015 Ecosphere, volume: 6, issue: 8, pages: art143 - art143

Abstract Insect-vectored plant diseases often create complex epidemiological systems that are challenging to understand, predict, and manage. An example is ‘bois noir' (BN), a phytoplasma-associated grapevine disease commonly found in European vineyards. Although BN has the potential to cause substantial economic damage, the factors that contribute to BN prevalence in vineyards are still not well understood. We used Bayesian inference with generalized linear mixed-effect models to test the hypotheses that (1) grapevine varieties exhibit different BN susceptibility; (2) environment drivers influence prevalence of the disease and occurrence of the vector; and (3) the presence of the main vector is a major determinant of BN occurrence. We found that the presence of the vector Hyalesthes obsoletus increased with increasing isothermality, minimum temperatures during the coldest period, soil erosion, and natural vegetation in close proximity to the vineyards. Presence of the BN disease increased with presence of the vector as well as increasing altitudes and mean annual temperatures. After accounting for those factors, Chardonnay and Riesling showed higher disease prevalence than Müller-Thurgau, Silvaner, and Merlot. Although the vector had an overall positive effect on the disease prevalence, disease and vector occurrence show distinct spatial patterns. In conclusion, our analysis suggests that vector presence is not the only, and maybe not the most important factor for BN disease prevalence. Environment and grape cultivar also play important roles. Hence, area-wide predictions of both environmental disease risk and vector presence, together with information about the susceptibility of grape cultivars, will enable a more targeted disease management. Our modelling framework could easily be applied to other diseases of concern, such as apple proliferation or flavescence dorée.
Carroll, C., Lawler, J. J., Roberts, D. R., Hamann, A.
Biotic and climatic velocity identify contrasting areas of vulnerability to climate change
2015 Plos One, volume: 10, issue: 10, page: e0140486

Abstract Metrics that synthesize the complex effects of climate change are essential tools for mapping future threats to biodiversity and predicting which species are likely to adapt in place to new climatic conditions, disperse and establish in areas with newly suitable climate, or face the prospect of extirpation. The most commonly used of such metrics is the velocity of climate change, which estimates the speed at which species must migrate over the earth’s surface to maintain constant climatic conditions. However, “analog-based” velocities, which represent the actual distance to where analogous climates will be found in the future, may provide contrasting results to the more common form of velocity based on local climate gradients. Additionally, whereas climatic velocity reflects the exposure of organisms to climate change, resultant biotic effects are dependent on the sensitivity of individual species as reflected in part by their climatic niche width. This has motivated development of biotic velocity, a metric which uses data on projected species range shifts to estimate the velocity at which species must move to track their climatic niche. We calculated climatic and biotic velocity for the Western Hemisphere for 1961–2100, and applied the results to example ecological and conservation planning questions, to demonstrate the potential of such analog-based metrics to provide information on broad-scale patterns of exposure and sensitivity. Geographic patterns of biotic velocity for 2954 species of birds, mammals, and amphibians differed from climatic velocity in north temperate and boreal regions. However, both biotic and climatic velocities were greatest at low latitudes, implying that threats to equatorial species arise from both the future magnitude of climatic velocities and the narrow climatic tolerances of species in these regions, which currently experience low seasonal and interannual climatic variability. Biotic and climatic velocity, by approximating lower and upper bounds on migration rates, can inform conservation of species and locally-adapted populations, respectively, and in combination with backward velocity, a function of distance to a source of colonizers adapted to a site’s future climate, can facilitate conservation of diversity at multiple scales in the face of climate change.
Alter, S.E., Meyer, M., Post, K., Czechowski, P., Gravlund, P., Gaines, C., Rosenbaum, H.C., Kaschner, K., Turvey, S.T., van der Plicht, J., Shapiro, B., Hofreiter, M.
Climate impacts on transocean dispersal and habitat in gray whales from the Pleistocene to 2100
2015 Mol Ecol, volume: 24, issue: 7, pages: 1510 - 1522

Abstract Arctic animals face dramatic habitat alteration due to ongoing climate change. Understanding how such species have responded to past glacial cycles can help us forecast their response to today's changing climate. Gray whales are among those marine species likely to be strongly affected by Arctic climate change, but a thorough analysis of past climate impacts on this species has been complicated by lack of information about an extinct population in the Atlantic. While little is known about the history of Atlantic gray whales or their relationship to the extant Pacific population, the extirpation of the Atlantic population during historical times has been attributed to whaling. We used a combination of ancient and modern DNA, radiocarbon dating and predictive habitat modelling to better understand the distribution of gray whales during the Pleistocene and Holocene. Our results reveal that dispersal between the Pacific and Atlantic was climate dependent and occurred both during the Pleistocene prior to the last glacial period and the early Holocene immediately following the opening of the Bering Strait. Genetic diversity in the Atlantic declined over an extended interval that predates the period of intensive commercial whaling, indicating this decline may have been precipitated by Holocene climate or other ecological causes. These first genetic data for Atlantic gray whales, particularly when combined with predictive habitat models for the year 2100, suggest that two recent sightings of gray whales in the Atlantic may represent the beginning of the expansion of this species' habitat beyond its currently realized range.
Barriga, P. A., Dormann, C. F., Gbur, E. E., Sagers, C. L.
Community structure and ecological specialization in plant–ant interactions
2015 J Trop Ecol, volume: 31, pages: 325 - 334

Abstract Environmental effects on species interactions can be studied by comparative analyses of network structure. For example, comparison of interaction networks among study sites can provide clues to geographic variation of host breadth. Obligate plant–ant interactions are ideal systems to explore these phenomena because they are long term and can be accurately sampled in the field. We tested two hypotheses: (1) network structure and host specialization do not vary among communities, and (2) the effects of plant extinction do not vary among communities.We sampled 10 or more plants for each of the 30 ant–plant species found in three Neotropical locations. We found that network specialization,H2′, was significantlyhigher than expected in random networks. The ant or plant specialization index, d′, distributiondidnot vary among localities,neither varied in link or asymmetry distribution.Plant extinctionsimulations showed that these interactions are vulnerable to plant loss, and the null model was more robust than the observed networks. This study provides a foundation onwhich plant and ant phylogenies can be added to explore compartment evolution.
Kraan, C., Dormann, C. F., Greenfield, B. L., Thrush, S. F.
Cross-scale variation in biodiversity- environment links illustrated by coastal sandflat communities
2015 Plos One, volume: 10, issue: 11, page: e0142411

Abstract Spatial variation in the composition of communities is the product of many biotic and environmental interactions. A neglected factor in the analysis of community distribution patterns is the multi-scale nature of the data, which has implications for understanding ecological processes and the development of conservation and environmental management practice. Drawing on recently established multivariate spatial analyses, we investigate whether including relationships between spatial structure and abiotic variables enable us to better discern patterns of species and communities across scales. Data comprised 1200 macrozoobenthic samples collected over an array of distances (30 cm to 1 km) in three New Zealand harbours, as well as commonly used abiotic variables, such as sediment characteristics and chlorophyll a concentrations, measured at the same scales. Moran’s eigenvector mapping was used to extract spatial scales at which communities were structured. Benthic communities, representing primarily bivalves, polychaetes and crustaceans, were spatially structured at four spatial scales, i.e. >100 m, 50–100 m, 50–15 m, and < 15 m. A broad selection of abiotic variables contributed to the large-scale variation, whereas a more limited set explained part of the fine-scale community structure. Across all scales, less than 30% of the variation in spatial structure was captured by our analysis. The large number of species (48) making up the 10 highest species scores based on redundancy analyses illustrate the variability of species-scale associations. Our results emphasise that abiotic variables and biodiversity are related at all scales investigated and stress the importance of assessing the relationship between environmental variables and the abundance and distribution of biological assemblages across a range of different scales.
Van Bressem, M.-F., Simões-Lopes, P. C., Félix, F., Kiszka, J. J., Daura-Jorge, F. G., Avila, I. C., Secchi, E. R., Flach, L., Fruet, P. F., du Toit, K., Ott, P. H., Elwen, S., Di Giacomo, A. B., Wagner, J., Banks, A., Van Waerebeek, K.
Epidemiology of lobomycosis-like disease in bottlenose dolphins 'tursiops spp.' from South America and southern Africa
2015 Dis Aquat Organ, volume: 117, pages: 59 - 75

Abstract We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere.
Latifi, H., Heurich, M., Hartig, F., Müller, J., Krzystek, P., Jehl, H., Dech, S.
Estimating over- and understorey canopy density of emperate mixed stands by airborne LiDAR data
2015 Forestry, volume: 0, pages: 1 - 13

Abstract Estimating forest structural attributes is one of the essential forestry-related remote sensing applications. The methods applied so far typically concentrate on the structure of the overstorey. For various conservation and management applications, however, information on lower layers is also of great interest. Detecting understorey cover by remote sensing is challenging, as passive sensors do not penetrate to the forest ground layer. An alternative to these is 3D metrics fromactive light detection and ranging (LiDAR). Here,we evaluate this technique for describing the vegetation density of multiple stand layers within the temperate stands of a large protected area in southeastern Germany. We combined LiDAR metrics and information on forest habitat types with regression models to investigate LiDAR metrics that are significantly correlated with vegetation density. The top canopy and the herbal layer showed strong correlations with the applied LiDAR metrics, whereas the predictive power was lower for the intermediate stand layers. Moreover, our results suggest that the relationship between LiDAR predictors and vegetation density depends on the forest type.Acomparison of the regression models with randomforest predictions showed no major improvement in predictive error. In conclusion, this study highlights the value of the LiDAR metrics for characterizing the structural properties of lower forest layers, which has implications for wildlife and forest management applications, especially in protected areas.
Gbedomon, R. C., Fandohan, A. B., Salako, V. K., Idohou, A. F. R., Kakaї, R. G., Achille Ephrem Assogbadjo
Factors affecting home gardens ownership, diversity and structure: a case study from Benin
2015 J Ethnobiol Ethnomed, volume: 11, page: 56

Abstract Background: Home gardens (HGs) provide perspectives for conservation of plant genetic resources while contributing to improving livelihoods. However, knowledge of local factors shaping their ownership, plant diversity (PD) and structure is still limited especially in West-Africa, where food insecurity is acute. This is critical to ensure effective mainstreaming of HGs into future biodiversity conservation and food production policies. Methods: Socio-economic and PD data were obtained from individual interviews (n = 470) and gardens inventories (n = 235) spanning humid, sub-humid and semi-arid zones of Benin. Generalised Linear Models, Hierarchical Cluster Analysis, Principal Component Analysis and Simple Correspondence Analysis were performed to examine socio-economic characteristics (age, gender, education level and main economic activity) affecting HGs ownership, and their effect coupled with intrinsic HGs characteristics (size, age) on PD and structure within HGs, across contrasting bio-geographical regions. Results: HG ownership was significantly dependent upon a complex relationship between age, gender and education level of the farmers. The probability to own HG increased with age with an early involvement in home gardening for women. Similarly, with increasing age, it was more likely to find a male owner than a female owner among the uneducated informants and those of primary school. Inversely, it was more likely to find female owner than a male owner among secondary school level or more. PD increased with increasing owner age and size of the HG. Larger and more diversified HGs were found in sub-humid and semi-arid zones while smaller and less diversified HGs were encountered in the humid zone. HGs were multi-layered. Based on the prevailing plant groups, three categories of HG were distinguished: Herb based gardens, Herb and Shrub/Trees based gardens, and Palm and Liana based gardens. Their prevalence was dependent upon bio-geographical zones and HG owner socio-economic characteristics, with herbs based HGs being mainly associated to women. Conclusion: Results suggest effects of complex interactions between socio-economic factors on HG ownership, and influence of these effects combined with intrinsic characteristics of HGs on PD. The early involvement of women in home gardening and their particular interest in herbs and shrubs are important assets for future conservation strategies based on HG and food production. Interventions are required to interfere with declining PD in HG across generations to accommodate multiple ecosystem service benefits.
Morin, P. A., Parsons, K. M., Archer, F. I., Ávila-Arcos, M. C., Barrett-Lennard, L. G., Dalla Rosa, L., Duchêne, S., Durban, J. W., Ellis, G. M., Ferguson, S. H., Ford, J. K., Ford, M. J., Garilao, C., Gilbert, M. T. P., Kaschner, K., Matkin, C. O., Petersen, S. D., Robertson, K. M., Visser, I. N., Wade, P. R., Ho, S. Y. W., Foote, A. D.
Geographic and temporal dynamics of a global radiation and diversification in the killer whale
2015 Mol Ecol, volume: 24, issue: 15, pages: 3964 - 3979

Abstract Global climate change during the Late Pleistocene periodically encroached and then released habitat during the glacial cycles, causing range expansions and contractions in some species. These dynamics have played a major role in geographic radiations, diversification and speciation. We investigate these dynamics in the most widely distributed of marine mammals, the killer whale (Orcinus orca), using a global data set of over 450 samples. This marine top predator inhabits coastal and pelagic ecosystems ranging from the ice edge to the tropics, often exhibiting ecological, behavioural and morphological variation suggestive of local adaptation accompanied by reproductive isolation. Results suggest a rapid global radiation occurred over the last 350 000 years. Based on habitat models, we estimated there was only a 15% global contraction of core suitable habitat during the last glacial maximum, and the resources appeared to sustain a constant global effective female population size throughout the Late Pleistocene. Reconstruction of the ancestral phylogeography highlighted the high mobility of this species, identifying 22 strongly supported long-range dispersal events including interoceanic and interhemispheric movement. Despite this propensity for geographic dispersal, the increased sampling of this study uncovered very few potential examples of ancestral dispersal among ecotypes. Concordance of nuclear and mitochondrial data further confirms genetic cohesiveness, with little or no current gene flow among sympatric ecotypes. Taken as a whole, our data suggest that the glacial cycles influenced local populations in different ways, with no clear global pattern, but with secondary contact among lineages following long-range dispersal as a potential mechanism driving ecological diversification.
Moran, E. V., Hartig, F., Bell, D. M.
Intraspecific trait variation across scales: implications for understanding global change responses
2015 Global Change Biol, volume: 22, issue: 1, pages: 137 - 150

Abstract Recognition of the importance of intraspecific variation in ecological processes has been growing, but empirical studies and models of global change have only begun to address this issue in detail. This review discusses sources and patterns of intraspecific trait variation and their consequences for understanding how ecological processes and patterns will respond to global change. We examine how current ecological models and theories incorporate intraspecific variation, review existing data sources that could help parameterize models that account for intraspecific variation in global change predictions, and discuss new data that may be needed. We provide guidelines on when it is most important to consider intraspecific variation, such as when trait variation is heritable or when nonlinear relationships are involved. We also highlight benefits and limitations of different model types and argue that many common modeling approaches such as matrix population models or global dynamic vegetation models can allow a stronger consideration of intraspecific trait variation if the necessary data are available. We recommend that existing data need to be made more accessible, though in some cases, new experiments are needed to disentangle causes of variation.
de Avila, A. L., Ruschel, A. R., Pereira de Carvalho, J. O., Mazzei, L., Macedo Silva, J. N., Lopes, J. C, Machado Araujo, M., Dormann, C. F., Bauhus, J.
Medium-term dynamics of tree species composition in response to silvicultural intervention intensities in a tropical rain forest
2015 Biol Conserv, volume: 191, pages: 577 - 586

Abstract Managed forests are important landscape components in tropical regions and may contribute to biodiversity conservation. Yet, managing tropical forests sustainably requires an understanding of ecosystem responses to silvicultural interventions. We investigated how silvicultural intervention intensity affects tree species composition and diversity over 30 years in the Brazilian Amazon by comparing themto pre-logging conditions and to an unlogged control. The interventions comprised logging in 1982 and thinning in 1993–1994 and ranged in intensity from19 to 53% reduction in the original basal area (BA). Trees with a diameter at breast height (DBH) ≥5 cm were measured on eight occasions in 41 permanent sample plots of 0.25 ha each. Silvicultural intervention intensity influenced both tree species composition and its trajectorywithin 30 years. In contrast, tree species diversity was not impaired. High intervention intensities (with BA reduction N 6.6m2 ha−1) had a substantial influence on the community of trees (DBH ≥ 10 cm), which did not show signs of return to pre-logging species composition. The reduction of BA through harvesting damage and thinning had a stronger effect on species composition than logging of mature trees itself. Thus, damage should be kept to a minimal level and strong thinning interventions should be avoided. Thismay enhance ecosystemrecovery and maintenance of biodiversity at other trophic levels. Since current permitted harvesting intensities in the Brazilian Amazon are lower than the lowest intensity examined in our study, legal harvesting practices are unlikely to cause substantial, long-term changes in tree species composition.
Ciuti, S., Jensen, W. F., Nielsen, S. E., Boyce, M. S.
Predicting mule deer recruitment from climate oscillations for harvest management on the northern Great Plains
2015 The Journal of Wildlife Management, volume: 79, issue: 8, pages: 1937 - 2817

Abstract We analyzed a unique 51-year time series for a population of mule deer in the North Dakota badlands, USA to examine the effects of seasonal weather on autumn recruitment. Winter weather recorded prior to birth of fawns and weather conditions recorded during spring the previous year (lagged effect), but not during spring or summer after birth, were related to observed patterns in autumn recruitment. When deer density was low (approx. 1 deer/km2) during the 1960s, fawn/female ratios were high ranging from 1.1 to 1.4 when minimum temperatures during the prior winter averaged −16° C and −8° C, respectively. Likewise, during the 2000s, when deer density was high (approx. 3 deer/km2), fawn/female ratios ranged from 0.6 to 0.9 when minimum daily temperatures during the previous winter were −16° C and −8° C, respectively. Large-scale Pacific-based climatic indices (>2,000 km to the Pacific coast) were correlated with local weather and helped explain variability in autumn recruitment. Higher values of the multivariate el niño southern oscillation and Pacific decadal oscillation were correlated with warmer and drier winters in the North Dakota badlands, whereas the North Pacific Index was correlated with colder and snowy winters. The ability to predict recruitment from local weather or from broad-scale climate indices (oscillations) provides greater opportunities for conservation and management, such as adjusting harvest quotas prior to autumn harvest. © 2015 The Wildlife Society.
Yaoitcha, A. S., Houehanou, T. D., Fandohan, A. B., Houinato, M. R. B.
Prioritization of useful medicinal tree species for conservation in Wari-Maro Forest Reserve in Benin: A multivariate analysis approach
2015 Forest Policy Econ

Abstract Prioritization of medicinal plant species in conservation schemes is critically important in low income countries. This paper aimed at developing a multivariate prioritization approach to guide conservation of medicinal tree species ofWari-Maro Forest Reserve in central Benin. Ethnobotany surveyswere conducted in communities surrounding the forest, using individual semi-structured interviews with 149 people. Additionally, 42 plots were established in the forest to assess the availability of reported species, using mensuration of ecological indicators. Ethnobotanical indices, harvesting risk index, economic importance, threat status, adaptability to climate variations and ecological indicators were computed and pulled into principal components for each species, to yield a compound priority value. Overall, 73 medicinal tree species were reported for 94 traditional medicinal uses. Using our approach, twelve species emerged as priority species for conservation. The most important priority species were Afzelia africana, Khaya senegalensis, Milicia excelsa and Pterocarpus erinaceus. Local perceptions on the availability of three of these specieswere perfectly congruent with ecological indicators. Enrichment planting and assisted rejuvenation were suggested as urgent conservation actions to be taken
Benadi, G.
Requirements for plant coexistence through pollination niche partitioning
2015 Proc. R. Soc. B, volume: 282, issue: 1810, page: 20150117

Abstract Plant–pollinator interactions are often thought to have been a decisive factor in the diversification of flowering plants, but to be of little or no importance for the maintenance of existing plant diversity. In a recent opinion paper, Pauw (2013 Trends Ecol. Evol. 28, 30–37. (doi:10.1016/j.tree.2012.07.019)) challenged this view by proposing a mechanism of diversity maintenance based on pollination niche partitioning. In this article, I investigate under which conditions the mechanism suggested by Pauw can promote plant coexistence, using a mathematical model of plant and pollinator population dynamics. Numerical simulations show that this mechanism is most effective when the costs of searching for flowers are low, pollinator populations are strongly limited by resources other than pollen and nectar, and plant–pollinator interactions are sufficiently specialized. I review the empirical literature on these three requirements, discuss additional factors that may be important for diversity maintenance through pollination niche partitioning, and provide recommendations on how to detect this coexistence mechanism in natural plant communities.
Budic, L., Didenko, G., Dormann, C. F.
Squares of different sizes: effect of geographical projection on model parameter estimates in species distribution modeling
2015 Ecol Evol, volume: 6, issue: 1, pages: 202 - 211

Abstract In species distribution analyses, environmental predictors and distribution data for large spatial extents are often available in long-lat format, such as degree ras- ter grids. Long-lat projections suffer from unequal cell sizes, as a degree of lon- gitude decreases in length from approximately 110 km at the equator to 0 km at the poles. Here we investigate whether long-lat and equal-area projections yield similar model parameter estimates, or result in a consistent bias. We analyzed the environmental effects on the distribution of 12 ungulate species with a northern distribution, as models for these species should display the strongest effect of projectional distortion. Additionally we choose four species with entirely continental distributions to investigate the effect of incomplete cell cov- erage at the coast. We expected that including model weights proportional to the actual cell area should compensate for the observed bias in model coeffi- cients, and similarly that using land coverage of a cell should decrease bias in species with coastal distribution. As anticipated, model coefficients were differ- ent between long-lat and equal-area projections. Having progressively smaller and a higher number of cells with increasing latitude influenced the importance of parameters in models, increased the sample size for the northernmost parts of species ranges, and reduced the subcell variability of those areas. However, this bias could be largely removed by weighting long-lat cells by the area they cover, and marginally by correcting for land coverage. Overall we found little effect of using long-lat rather than equal-area projections in our analysis. The fitted relationship between environmental parameters and occurrence probabil- ity differed only very little between the two projection types. We still recom- mend using equal-area projections to avoid possible bias. More importantly, our results suggest that the cell area and the proportion of a cell covered by land should be used as a weight when analyzing distribution of terrestrial species.
Latifi, H., Fassnacht, F.E., Hartig, F., Bergere, C., Hernández, J., Corvalán, P., Koch, B.
Stratified aboveground forest biomass estimation by remote sensing data
2015 Int J Appl Earth Obs, volume: 38, pages: 229 - 241

Abstract Remote sensing-assisted estimates of aboveground forest biomass are essential for modeling carbon budgets. It has been suggested that estimates can be improved by building species- or strata-specific biomass models. However, few studies have attempted a systematic analysis of the benefits of such stratification, especially in combination with other factors such as sensor type, statistical prediction method and sampling design of the reference inventory data. We addressed this topic by analyzing the impact of stratifying forest data into three classes (broadleaved, coniferous and mixed forest). We compare predictive accuracy (a) between the strata (b) to a case without stratification for a set of pre-selected predictors from airborne LiDAR and hyperspectral data obtained in a managed mixed forest site in southwestern Germany. We used 5 commonly applied algorithms for biomass predictions on bootstrapped subsamples of the data to obtain cross validated RMSE and r2 diagnostics. Those values were analyzed in a factorial design by an analysis of variance (ANOVA) to rank the relative importance of each factor. Selected models were used for wall-to-wall mapping of biomass estimates and their associated uncertainty. The results revealed marginal advantages for the strata-specific prediction models over the unstratified ones, which were more obvious on the wall-to-wall mapped area-based predictions. Yet further tests are necessary to establish the generality of these results. Input data type and statistical prediction method are concluded to remain the two most crucial factors for the quality of remote sensing-assisted biomass models.
Halbig, P., Henke, L., Poirot, J., Wagenhoff, E., Delb, H., Klimetzek, D.
The pine processionary moth in the Upper Rhine Valley: Climatic resistance and development of an isolated occurrence. 111-113 in: Roques A (ed.): Processionary moths and climate change: an update.
2015 Springer, page: 427pp
Lohrer, A. M., Thrush, S. F., Hewitt, J. E., Kraan, C.
The up-scaling of ecosystem functions in a heterogeneous world
2015 Scientific reports, volume: 5, page: 10349

Abstract Earth is in the midst of a biodiversity crisis that is impacting the functioning of ecosystems and the delivery of valued goods and services. However, the implications of large scale species losses are often inferred from small scale ecosystem functioning experiments with little knowledge of how the dominant drivers of functioning shift across scales. Here, by integrating observational and manipulative experimental field data, we reveal scale-dependent influences on primary productivity in shallow marine habitats, thus demonstrating the scalability of complex ecological relationships contributing to coastal marine ecosystem functioning. Positive effects of key consumers (burrowing urchins, Echinocardium cordatum) on seafloor net primary productivity (NPP) elucidated by short-term, single-site experiments persisted across multiple sites and years. Additional experimentation illustrated how these effects amplified over time, resulting in greater primary producer biomass sediment chlorophyll a content (Chla) in the longer term, depending on climatic context and habitat factors affecting the strengths of mutually reinforcing feedbacks. The remarkable coherence of results from small and large scales is evidence of real-world ecosystem function scalability and ecological self-organisation. This discovery provides greater insights into the range of responses to broad-scale anthropogenic stressors in naturally heterogeneous environmental settings.
Avila, I. C., Correa, L. M., Parsons, E. C. M.
Whale-watching activity in Bahía Málaga, on the pacific coast of Colombia, and its effect on humpback whale ('Megaptera Novaeangliae') behavior
2015 Tourism in Marine Environments, volume: 11, pages: 19 - 32(14)

Abstract During the whale-watching season of 2008, 6,663 whale watchers and 267 boat trips were recorded in Bahía Málaga, Colombia. Forty-four percent of humpback whale pods sighted in the area were approached by boats. Operators in 2008 did not comply with Colombian whale-watching guidelines during most encounters. The modal distance between whales and boats was 50 m. Ninety-four percent of boats approached too fast (>3 knots), and 78.6% of them approached mother–calf pods. On average, a pod of whales was observed for 42.6 minutes (SD 33.1), and by more than one boat in 60.2% of cases. As a consequence of boats' presence, whales modified their behavior by reducing blows per minute, moved faster and more erratically, increased breaching frequency, and decreased resting behavior.

2014

Dormann, C. F., Strauss, R.
A method for detecting modules in quantitative bipartite networks
2014 Methods Ecol Evol, volume: 5, issue: 1, pages: 90 - 98

Abstract Ecological networks are often composed of different subcommunities (often referred to as modules). Identifying such modules has the potential to develop a better understanding of the assembly of ecological communities and to investigate functional overlap or specialization. The most informative form of networks are quantitative or weighted networks. Here, we introduce an algorithm to identify modules in quantitative bipartite (or two-mode) networks. It is based on the hierarchical random graphs concept of Clauset et al. (2008 Nature 453: 98–101) and is extended to include quantitative information and adapted to work with bipartite graphs. We define the algorithm, which we call QuanBiMo, sketch its performance on simulated data and illustrate its potential usefulness with a case study. Modules are detected with a higher accuracy in simulated quantitative networks than in their binary counterparts. Even at high levels of noise, QuanBiMo still classifies 70% of links correctly as within- or between-modules. Recursively applying the algorithm results in additional information of within-module organization of the network. The algorithm introduced here must be seen as a considerable improvement over the current standard of algorithms for binary networks. Due to its higher sensitivity, it is likely to lead to be useful for detecting modules in the typically noisy data of ecological networks.
Gerstner, K., Dormann, C. F., Václavík, T., Kreft, H., Seppelt, R.
Accounting for geographic variation in species-area relationships improves the prediction of plant species richness at the global scale.
2014 J Biogeogr, volume: 41, pages: 261 - 273

Abstract The species–area relationship (SAR) is a prominent concept for predicting species richness and biodiversity loss. A key step in defining SARs is to accurately estimate the slope of the relationship, but researchers typically apply only one global (canonical) slope. We hypothesized that this approach is overly simplistic and investigated how geographically varying determinants of SARs affect species richness estimates of vascular plants at the global scale.
Thurfjell, H., Ciuti, S., Boyce, M.S.
Applications of step-selection functions in ecology and conservation
2014 Movement Ecology, volume: 2, page: 4

Abstract Recent progress in positioning technology facilitates the collection of massive amounts of sequential spatial data on animals. This has led to new opportunities and challenges when investigating animal movement behaviour and habitat selection. Tools like Step Selection Functions (SSFs) are relatively new powerful models for studying resource selection by animals moving through the landscape. SSFs compare environmental attributes of observed steps (the linear segment between two consecutive observations of position) with alternative random steps taken from the same starting point. SSFs have been used to study habitat selection, human-wildlife interactions, movement corridors, and dispersal behaviours in animals. SSFs also have the potential to depict resource selection at multiple spatial and temporal scales. There are several aspects of SSFs where consensus has not yet been reached such as how to analyse the data, when to consider habitat covariates along linear paths between observations rather than at their endpoints, how many random steps should be considered to measure availability, and how to account for individual variation. In this review we aim to address all these issues, as well as to highlight weak features of this modelling approach that should be developed by further research. Finally, we suggest that SSFs could be integrated with state-space models to classify behavioural states when estimating SSFs.

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Mupepele, A.-C., Müller, T., Dittrich, M., Floren, A.
Are temperate canopy spiders tree-species specific?
2014 Plos One, volume: 9, issue: 2, page: e86571

Abstract Arboreal spiders in deciduous and coniferous trees were investigated on their distribution and diversity. Insecticidal knockdown was used to comprehensively sample spiders from 175 trees from 2001 to 2003 in the Białowiez_a forest and three remote forests in Poland. We identified 140 species from 9273 adult spiders. Spider communities were distinguished between deciduous and coniferous trees. The richest fauna was collected from Quercus where beta diversity was also highest. A tree-species-specific pattern was clearly observed for Alnus, Carpinus, Picea and Pinus trees and also for those tree species that were fogged in only four or three replicates, namely Betula and Populus. This hitherto unrecognised association was mainly due to the community composition of common species identified in a Dufrene-Legendre indicator species analysis. It was not caused by spatial or temporal autocorrelation. Explaining tree-species specificity for generalist predators like spiders is difficult and has to involve physical and ecological tree parameters like linkage with the abundance of prey species. However, neither did we find a consistent correlation of prey group abundances with spiders nor could differences in spider guild composition explain the observed pattern. Our results hint towards the importance of deterministic mechanisms structuring communities of generalist canopy spiders although the casual relationship is not yet understood.
Certain, G., Dormann, C. F., Planque, B.
Choices of abundance currency, community definition and diversity metric control the predictive power of macroecological models of biodiversity
2014 Global Ecol Biogeogr, volume: 23, issue: 4, pages: 468 - 478

Abstract This study focuses on the influence of methodological choices on the predictive performance of macroecological models (MEMs), i.e. statistical models designed to predict patterns of biodiversity using environmental predictors. We emphasize the influence of three methodological choices: (1) the choice of the currency in which the abundance of each species is measured, i.e. numbers of individuals or biomass; (2) the rules used to define the species assemblage under focus, i.e. broad communities or refined ecological guilds; and (3) the influence of rare over common species in the biodiversity measure.
Elfström, M., Zedrosser, A., Jerina, K., Støen, O.-G., Kindberg, J., Budic, L., Jonozovič, M., Swenson, J. E.
Does despotic behavior or food search explain the occurrence of problem brown bears in Europe?
2014 J Wildlife Manage, volume: 78, pages: 881 - 893

Abstract Bears foraging near human developments are often presumed to be responding to food shortage, but this explanation ignores social factors, in particular despotism in bears. We analyzed the age distribution and body condition index (BCI) of shot brown bears in relation to densities of bears and people, and whether the shot bears were killed by managers (i.e., problem bears; n = 149), in self-defense (n = 51), or were hunter-killed nonproblem bears (n = 1,896) during 1990–2010. We compared patterns between areas with (Slovenia) and without supplemental feeding (Sweden) of bears relative to 2 hypotheses. The food-search/food-competition hypothesis predicts that problem bears should have a higher BCI (e.g., exploiting easily accessible and/or nutritious human-derived foods) or lower BCI (e.g., because of food shortage) than nonproblem bears, that BCI and human density should have a positive correlation, and problem bear occurrence and seasonal mean BCI of nonproblem bears should have a negative correlation (i.e., more problem bears during years of low food availability). Food competition among bears additionally predicts an inverse relationship between BCI and bear density. The safety-search/naivety hypothesis (i.e., avoiding other bears or lack of human experience) predicts no relationship between BCI and human density, provided no dietary differences due to spatiotemporal habitat use among bears, no relationship between problem bear occurrence and seasonal mean BCI of nonproblem bears, and does not necessarily predict a difference between BCI for problem/nonproblem bears. If food competition or predation avoidance explained bear occurrence near settlements, we predicted younger problem than nonproblem bears and a negative correlation between age and human density. However, if only food search explained bear occurrence near settlements, we predicted no relation between age and problem or nonproblem bear status, or between age and human density. We found no difference in BCI or its variability between problem and nonproblem bears, no relation between BCI and human density, and no correlation between numbers of problem bears shot and seasonal mean BCI for either country. The peak of shot problem bears occurred from April to June in Slovenia and in June in Sweden (i.e., during the mating period when most intraspecific predation occurs and before fall hyperphagia). Problem bears were younger than nonproblem bears, and both problem and nonproblem bears were younger in areas of higher human density. These age differences, in combination with similarities in BCI between problem and nonproblem bears and lack of correlation between BCI and human density, suggested safety-search and naïve dispersal to be the primary mechanisms responsible for bear occurrence near settlements. Younger bears are less competitive, more vulnerable to intraspecific predation, and lack human experience, compared to adults. Body condition was inversely related to the bear density index in Sweden, whereas we found no correlation in Slovenia, suggesting that supplemental feeding may have reduced food competition, in combination with high bear harvest rates. Bears shot in self-defense were older and their BCI did not differ from that of nonproblem bears. Reasons other than food shortage apparently explained why most bears were involved in encounters with people or viewed as problematic near settlements in our study. © 2014 The Wildlife Society.
Hartig, F., Dormann, C. F.
Does “model-free” forecasting really outperform the “true” model?
2014 PNAS, volume: 110, issue: E397

Abstract Estimating population models from uncertain observations is an important problem in ecology. Perretti et al. observed that standard Bayesian state–space solutions to this problem may provide biased parameter estimates when the underlying dynamics are chaotic (1). Consequently, forecasts based on these estimates showed poor predictive accuracy compared with simple “model-free” methods, which lead Perretti et al. to conclude that “Model-free forecasting outperforms the correct mechanistic model for simulated and experimental data.” However, a simple modification of the statistical methods also suffices to remove the bias and reverse their results.
Pe'er, G., Dicks, L.V., Visconti, P., Arlettaz, R., Báldi, A., Benton, T.G., Collins, S., Dieterich, M., Gregory, R.D., Hartig, F., Henle, K., Hobson, P.R., Kleijn, D., Neumann, R.K., Robijns, T., Schmidt, J., Shwartz, A., Sutherland, W.J., Turbé, A., Wulf, F., Scott, A.V.
EU agricultural reform fails on biodiversity
2014 Science, volume: 344, issue: 6188, pages: 1090 - 1092

Abstract In December 2013, the European Union (EU) enacted the reformed Common Agricultural Policy (CAP) for 2014–2020, allocating almost 40% of the EU's budget and influencing management of half of its terrestrial area. Many EU politicians are announcing the new CAP as “greener,” but the new environmental prescriptions are so diluted that they are unlikely to benefit biodiversity. Individual Member States (MSs), however, can still use flexibility granted by the new CAP to design national plans to protect farmland habitats and species and to ensure long-term provision of ecosystem services.
van Teeffelen, J.A., Opdamb, P., Wätzold, F., Hartig, F., Johste, K., Drechslere, M., Vos, C.C., Wissel, S., Quétier, F.
Ecological and economic conditions and associated institutional challenges for conservation banking in dynamic landscapes
2014 Landscape and Urban Planning, volume: 130, pages: 64 - 72

Abstract Protected areas are a cornerstone of current biodiversity policy. The continued loss of biodiversity, however, as well as the limited scope to extend protected area networks necessitates a conservation perspective that encompasses both protected areas and the wider landscape. This calls for policy instruments that can govern land use dynamics, simultaneously meeting demands for conservation (i.e. no net loss of biodiversity) and economic development. Conservation banking could be such an instrument, but only when certain criteria are met. Building on the theory of ecological networks, we combine ecological, economic and institutional perspectives on conservation banking to identify when and where conservation banking could be feasible. Economic prerequisites include sufficient market activity to match demand and supply. Adequate regulatory capacity is needed to design and enforce trading rules. From an ecological perspective, habitat turnover is least detrimental in large and well-connected networks. For many ecosystem types, those prerequisites will be rarely met in practice: sufficient market activity implies sufficient habitat turnover, but most ecological networks are not robust enough to buffer frequent habitat turnover. Therefore, banking is best limited to common and fast-regenerating ecosystem types (e.g. certain coastal systems, wetlands, nutrient-rich grasslands). Furthermore, conservation banking could be applied to a subset of the network only, i.e. the wider landscape, as a complementary instrument to protected area policy. With appropriate trading rules and institutional arrangements, the loss and gain of habitat could be governed to improve the spatial cohesion and size of ecological networks and the capacity of landscapes to support biodiversity.
Schleuning, M., Ingmann, L., Strauß, R., Fritz, S. A., Dalsgaard, B., Dehling, D. M., Plein, M., Saavedra, F., Sandel, B., Svenning, J. -C., Böhning-Gaese, K., Dormann, C. F.
Ecological, historical and evolutionary determinants of modularity in weighted seed-dispersal networks
2014 Ecol Lett, volume: 17, issue: 4, pages: 454 - 463

Abstract Modularity is a recurrent and important property of bipartite ecological networks. Although well-resolved ecological networks describe interaction frequencies between species pairs, modularity of bipartite networks has been analysed only on the basis of binary presence–absence data. We employ a new algorithm to detect modularity in weighted bipartite networks in a global analysis of avian seed-dispersal networks. We define roles of species, such as connector values, for weighted and binary networks and associate them with avian species traits and phylogeny. The weighted, but not binary, analysis identified a positive relationship between climatic seasonality and modularity, whereas past climate stability and phylogenetic signal were only weakly related to modularity. Connector values were associated with foraging behaviour and were phylogenetically conserved. The weighted modularity analysis demonstrates the dominating impact of ecological factors on the structure of seed-dispersal networks, but also underscores the relevance of evolutionary history in shaping species roles in ecological communities.
Gerstner, K., Dormann, C. F., Stein, A., Manceur, A. M., Seppelt, R.
Effects of land use on plant biodiversity - a global meta-analysis.
2014 J Appl Ecol, volume: 51, pages: 1690 - 1700

Abstract Plant diversity is globally threatened by anthropogenic land use including management and modification of the natural environment. At regional and local scales, numerous studies world-wide have examined land use and its effects on plant diversity, but evidence for declining species diversity is mixed. This is because, first, land use comes in many variations, hampering comparisons of studies. Second, land use directly affects the environment, but indirect effects extend beyond the boundaries of the land in use. Third, land-use effects greatly depend on the environmental, historical and socio-economic context. To evaluate the generality and variation of studies’ findings about land-use effects, we undertook a quantitative synthesis using meta-analytic techniques. Using 572 effect sizes from 375 studies distributed globally relating to 11 classes of land use, we found that direct and indirect effects of land use on plant diversity (measured as species richness) are variable and can lead to both local decreases and increases. Further, we found evidence (best AIC model) that land-use-specific covariables mostly determine effect-size variation and that in general land-use effects differ between biomes. Synthesis and applications. This extensive synthesis provides the most comprehensive and quantitative overview to date about the effects of the most widespread and relevant land-use options on plant diversity and their covariables. We found important covariables of specific land-use classes but little evidence that land-use effects can be generally explained by their environmental and socio-economic context. We also found a strong regional bias in the number of studies (i.e. more studies from Europe and North America) and highlight the need for an overarching and consistent land-use classification scheme. Thereby, our study provides a new vantage point for future research directions.
Apollonio, M., De Cena, F., Bongi, P., Ciuti, S.
Female preference and predation risk models can explain the maintenance of a Fallow deer ('Dama dama') Lek and its ‘handy’ location
2014 Plos One, volume: 9, issue: 3, page: e89852

Abstract We tested the predictions of three models (female preference; hotspot; predator avoidance) on lek formation in the fallow deer population of San Rossore, Tuscany. We collected behavioural observations in two leks and radiotracking data on 67 deer over 7 years. Two deer sub-populations were present in the northern and southern sides of the area, respectively, the two sectors being delimited by a river and including one lek each. Predictions were tested for one lek (SG), located in the south-side where we set up our 7-year radiotracking program. Data from a second lek (FO, north-side) were used to test those predictions which imply the occurrence of multiple leks in the same population. We showed that the majority of females made one single visit to one lek, only during the rut. The lek was located outside areas of higher female traffic and home range overlap, and females increased home range sizes during the rut to reach it. Twilight routes of females never crossed the lek; instead, females walked atypical routes and at a faster pace to reach the lek and mate. The distance between the two leks was higher than the average diameter of female home ranges, and only one lek was present within female home ranges. Males reached the lek one month before the arrival of females, corroborating that lekking is a female-initiated process (females moving towards large clumped male aggregations) rather than a male-initiated process (males moving towards female hotspots). Our results supported the female preference model, and rejected the predictions of the hotspot model. Also, leks were located far from areas with higher predation risk, supporting the predator avoidance model. The position of lek SG resulted ‘handy’ at the sub-population level because of the optimal trade-off between travel costs for females to reach it and avoidance of human predators.
Haynes, K.J., Allstadt, A.J., Klimetzek, D.
Forest defoliator outbreaks under climate change: effects on the frequency and severity of outbreaks of five pine insect pests
2014 Global Change Biol, volume: 20, pages: 2004 - 2018

Abstract To identify general patterns in the effects of climate change on the outbreak dynamics of forest-defoliating insect species, we examined a 212-year record (1800–2011) of outbreaks of five pine-defoliating species (Bupalus piniarius, Panolis flammea, Lymantria monacha, Dendrolimus pini, and Diprion pini) in Bavaria, Germany for the evidence of climate-driven changes in the severity, cyclicity, and frequency of outbreaks. We also accounted for historical changes in forestry practices and examined effects of past insecticide use to suppress outbreaks. Analysis of relationships between severity or occurrence of outbreaks and detrended measures of temperature and precipitation revealed a mixture of positive and negative relationships between temperature and outbreak activity. Two moth species (P. flammea and Dendrolimus pini) exhibited lower outbreak activity following years or decades of unusually warm temperatures, whereas a sawfly (Diprion pini), for which voltinism is influenced by temperature, displayed increased outbreak occurrence in years of high summer temperatures. We detected only one apparent effect of precipitation, which showed Dendrolimus pini outbreaks tending to follow drought. Wavelet analysis of outbreak time series suggested climate change may be associated with collapse of L. monacha and Dendrolimus pini outbreak cycles (loss of cyclicity and discontinuation of outbreaks, respectively), but high-frequency cycles for B. piniarius and P. flammea in the late 1900s. Regional outbreak severity was generally not related to past suppression efforts (area treated with insecticides). Recent shifts in forestry practices affecting tree species composition roughly coincided with high-frequency outbreak cycles in B. piniarius and P. flammea but are unlikely to explain the detected relationships between climate and outbreak severity or collapses of outbreak cycles. Our results highlight both individualistic responses of different pine-defoliating species to climate changes and some patterns that are consistent across defoliator species in this and other forest systems, including collapsing of population cycles.
Ensing, E.P., Ciuti, S., de Wijs, F.A.L.M., Lentferink, D.H., ten Hoedt, A., Boyce, M.S., Hut, R.A.
GPS based daily activity patterns in european red deer and north american elk ('Cervus elaphus'): Indication for a weak circadian clock in ungulates
2014 Plos One, volume: 9, issue: 9, page: e106997

Abstract Long-term tracking using global positioning systems (GPS) is widely used to study vertebrate movement ecology, including fine-scale habitat selection as well as large-scale migrations. These data have the potential to provide much more information about the behavior and ecology of wild vertebrates: here we explore the potential of using GPS datasets to assess timing of activity in a chronobiological context. We compared two different populations of deer ('Cervus elaphus'), one in the Netherlands (red deer), the other in Canada (elk). GPS tracking data were used to calculate the speed of the animals as a measure for activity to deduce unbiased daily activity rhythms over prolonged periods of time. Speed proved a valid measure for activity, this being validated by comparing GPS based activity data with head movements recorded by activity sensors, and the use of GPS locations was effective for generating long term chronobiological data. Deer showed crepuscular activity rhythms with activity peaks at sunrise (the Netherlands) or after sunrise (Canada) and at the end of civil twilight at dusk. The deer in Canada were mostly diurnal while the deer in the Netherlands were mostly nocturnal. On an annual scale, Canadian deer were more active during the summer months while deer in the Netherlands were more active during winter. We suggest that these differences were mainly driven by human disturbance (on a daily scale) and local weather (on an annual scale). In both populations, the crepuscular activity peaks in the morning and evening showed a stable timing relative to dawn and dusk twilight throughout the year, but marked periods of daily a-rhythmicity occurred in the individual records. We suggest that this might indicate that (changes in) light levels around twilight elicit a direct behavioral response while the contribution of an internal circadian timing mechanism might be weak or even absent.
Selig, E.R., Turner, W.R., Troëng, S., Wallace, B.P., Halpern, B.S., Kaschner, K., Lascelles, B.G., Carpenter, K.E., Mittermeier, R.A.
Global priorities for marine biodiversity conservation
2014 Plos One, volume: 9, issue: 1, page: e82898

Abstract In recent decades, many marine populations have experienced major declines in abundance, but we still know little about where management interventions may help protect the highest levels of marine biodiversity. We used modeled spatial distribution data for nearly 12,500 species to quantify global patterns of species richness and two measures of endemism. By combining these data with spatial information on cumulative human impacts, we identified priority areas where marine biodiversity is most and least impacted by human activities, both within Exclusive Economic Zones (EEZs) and Areas Beyond National Jurisdiction (ABNJ). Our analyses highlighted places that are both accepted priorities for marine conservation like the Coral Triangle, as well as less well-known locations in the southwest Indian Ocean, western Pacific Ocean, Arctic and Antarctic Oceans, and within semi-enclosed seas like the Mediterranean and Baltic Seas. Within highly impacted priority areas, climate and fishing were the biggest stressors. Although new priorities may arise as we continue to improve marine species range datasets, results from this work are an essential first step in guiding limited resources to regions where investment could best sustain marine biodiversity.
Killeen, J., Thurfjell, H., Ciuti, S., Paton, D., Musiani, M., Boyce, M.S.
Habitat selection during ungulate dispersal and exploratory movement at broad and fine scale with implications for conservation management.
2014 Movement ecology, volume: 2, page: 15

Abstract Dispersal has a critical influence on demography and gene flow and as such maintaining connectivity between populations is an essential element of modern conservation. Advances in satellite radiotelemetry are providing new opportunities to document dispersal, which previously has been difficult to study. This type of data also can be used as an empirical basis for defining landscapes in terms of resistance surfaces, enabling habitat corridors to be identified. However, despite the scale-dependent nature of habitat selection few studies have investigated selection specifically during dispersal. Here we investigate habitat selection during and around dispersal periods as well as the influence of age and sex on dispersal for a large ungulate.
Fassnacht, F., Hartig, F., Latific, H., Berger, C., Hernández, J., Corvalán, P., Koch, B.
Importance of sample size, data type and prediction method for remote sensing based estimations of aboveground forest biomass
2014 Remote Sens Environ, volume: 154, pages: 102 - 114

Abstract Estimates of forest biomass are needed for various technical and scientific applications, ranging from carbon and bioenergy policies to sustainable forest management. As local measurements are costly, there is a great interest in obtaining reliable estimates over large areas from remote sensing data. Currently, such estimates are obtained with a variety of data sources, statistical methods and prediction standards, and there is no agreement on what are best practices for this task. To improve our understanding of how these different methods affect prediction quality, we first conducted a systematic review of the available literature to identify the most common sensor types and prediction methods. Based on the review, we identified sample size of the reference points on the ground, prediction method (stepwise linear regression, support vector machines, random forest, Gaussian processes and k-nearest neighbor), and sensor type as the main differences that could potentially affect predictive quality. We then compared those factors in two case study areas in Germany and Chile, for which airborne discrete return Light Detection And Ranging (LiDAR) and airborne hyperspectral as well as airborne discrete return LiDAR and spaceborne hyperspectral data were available. For each factor combination, we calculated Pearson's coefficient of correlation between observations and predictions (r2) and root mean squared error (RMSE) for bootstrapped estimates using k-fold cross-validation with a varying number of folds. Finally, Analysis of Variance (ANOVA) was used to quantify the influence of the factors on the predictive error of the biomass models. Our results confirm previous findings that predictor data (sensor) type is the most important factor for the accuracy of biomass estimates, with LiDAR being preferable to hyperspectral data. In contrast to some previous studies, complementing LiDAR with hyperspectral data did not improve predictive accuracy. Also the prediction method had a substantial effect on accuracy and was generally more important than the sample size. In most cases, random forest performed best and stepwise linear models worst, judging from r2 and RMSE under cross-validation. Additional results suggested that r2 may deliver unrealistically large values when the hold-out sample during the cross-validation is too small. In conclusion, our literature review revealed that different methods for biomass estimation are currently used, with no general agreement on best practices. In our case studies, we found substantial accuracy differences between those methods, with LiDAR data, in combination with a random forest algorithm and a large number of reference sample units on the ground yielding the lowest error for biomass predictions. The comparatively high importance of the statistical prediction method seems particularly relevant, as they suggest that choosing the appropriate statistical method may be more effective than obtaining additional field data for obtaining good biomass estimates. Considering the costs of improving accuracy of global and regional biomass estimates by ground measurements, it seems sensible to invest in further comparative studies, preferably with a wider range of sites and including also RADAR sensors, to establish robust best-practice recommendations for obtaining regional and global biomass estimates from remote-sensing data.
Allan, E., Bossdorf, O., Dormann, C. F., Prati, D., Gossner, M., Tscharntke, T., et al.
Inter-annual variation in land-use intensity enhances grassland multidiversity.
2014 P Natl Acad Sci Usa, volume: 111, pages: 308 - 313

Abstract Although temporal heterogeneity is a well-accepted driver of biodiversity, effects of interannual variation in land-use intensity (LUI) have not been addressed yet. Additionally, responses to land use can differ greatly among different organisms; therefore, overall effects of land-use on total local biodiversity are hardly known. To test for effects of LUI (quantified as the combined intensity of fertilization, grazing, and mowing) and interannual variation in LUI (SD in LUI across time), we introduce a unique measure of whole-ecosystem biodiversity, multidiversity. This synthesizes individual diversity measures across up to 49 taxonomic groups of plants, animals, fungi, and bacteria from 150 grasslands. Multidiversity declined with increasing LUI among grasslands, particularly for rarer species and aboveground organisms, whereas common species and belowground groups were less sensitive. However, a high level of interannual variation in LUI increased overall multidiversity at low LUI and was even more beneficial for rarer species because it slowed the rate at which the multidiversity of rare species declined with increasing LUI. In more intensively managed grasslands, the diversity of rarer species was, on average, 18% of the maximum diversity across all grasslands when LUI was static over time but increased to 31% of the maximum when LUI changed maximally over time. In addition to decreasing overall LUI, we suggest varying LUI across years as a complementary strategy to promote biodiversity conservation.
Avila, I.C., Alava, J.J., Galvis, C.A.
On the presence of a vagrant Juan Fernández fur seal ('Arctocephalus philippii') in the Pacific coast of Colombia: a new extralimital record
2014 Journal of Neotropical Mammalogy, volume: 21, issue: 1, pages: 109 - 114

Abstract We report the first record of a male Juan Fernández fur seal, 'Arctocephalus philippii' (Peters, 1866), in the Colombian Pacific coast. The animal was mainly identified according to the external morphology of the head and snout. This observation is the first northernmost record for A. philippii in the Southeastern Pacific, with an extreme movement covering a total distance of approximately 3700-4600 km from its normal geographic range, including the Juan Fernández Archipelago and Desventuradas Islands (San Félix and San Ambrosio), Chile. This finding indicates that vagrant individuals can reach new sites in the Northern Hemisphere and could have a broader geographical displacement than previously thought.

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Hartig, F., Münkemüller, T., Johst, K., Dieckmann, U.
On the sympatric evolution and evolutionary stability of coexistence by relative nonlinearity of competition
2014 Plos One, volume: 9, issue: 9, page: e94454

Abstract If two species exhibit different nonlinear responses to a single shared resource, and if each species modifies the resource dynamics such that this favors its competitor, they may stably coexist. This coexistence mechanism, known as relative nonlinearity of competition, is well understood theoretically, but less is known about its evolutionary properties and its prevalence in real communities. We address this challenge by using adaptive dynamics theory and individual-based simulations to compare community stabilization and evolutionary stability of species that coexist by relative nonlinearity. In our analysis, evolution operates on the species' density-compensation strategies, and we consider a trade-off between population growth rates at high and low resource availability. We confirm previous findings that, irrespective of the particular model of density dependence, there are many combinations of overcompensating and undercompensating density-compensation strategies that allow stable coexistence by relative nonlinearity. However, our analysis also shows that most of these strategy combinations are not evolutionarily stable and will be outcompeted by an intermediate density-compensation strategy. Only very specific trade-offs lead to evolutionarily stable coexistence by relative nonlinearity. As we find no reason why these particular trade-offs should be common in nature, we conclude that the sympatric evolution and evolutionary stability of relative nonlinearity, while possible in principle, seems rather unlikely. We speculate that this may, at least in part, explain why empirical demonstrations of this coexistence mechanism are rare, noting, however, that the difficulty to detect relative nonlinearity in the field [...]
Benadi, G., Hovestadt, T., Poethke, H.-J., Blüthgen, N.
Specialization and phenological synchrony of plant–pollinator interactions along an altitudinal gradient.
2014 J Anim Ecol, volume: 83, pages: 639 - 650

Abstract One of the most noticeable effects of anthropogenic climate change is the shift in timing of seasonal events towards earlier occurrence. The high degree of variation in species' phenological shifts has raised concerns about the temporal decoupling of interspecific interactions, but the extent and implications of this effect are largely unknown. In the case of plant-pollinator systems, more specialized species are predicted to be particularly threatened by phenological decoupling, since they are assumed to be less flexible in the choice of interaction partners, but until now this hypothesis has not been tested. In this paper, we studied phenology and interactions of plant and pollinator communities along an altitudinal gradient in the Alps as a model for the possible effects of climate change in time. Our results show that even relatively specialized pollinators were much more flexible in their use of plant species as floral resources than their local flower visitation suggested. We found no relationship between local specialization of pollinators and the consistency of their visitation patterns across sites, and also no relationship between specialization and phenological synchrony of pollinators with particular plants. Thus, in contrast to the conclusions of a recent simulation study, our results suggest that most pollinator species included in this study are not threatened by phenological decoupling from specific flowering plants. However, the flexibility of many rarely observed pollinator species remains unknown. Moreover, our results suggest that specialized flower visitors select plant species based on certain floral traits such as the length of the nectar holder tube. If that is the case, the observed flexibility of plant-pollinator interactions likely depends on a high degree of functional redundancy in the plant community, which may not exist in less diverse systems.
Calabrese, J. M., Certain, G., Kraan, C., Dormann, C. F.
Stacking species distribution models and adjusting bias by linking them to macroecological models
2014 Global Ecol Biogeogr, volume: 23, pages: 1466 - 8238

Abstract Species distribution models (SDMs) are common tools in biogeography and conservation ecology. It has been repeatedly claimed that aggregated (stacked) SDMs (S-SDMs) will overestimate species richness. One recently suggested solution to this problem is to use macroecological models of species richness to constrain S-SDMs. Here, we examine current practice in the development of S-SDMs to identify methodological problems, provide tools to overcome these issues, and quantify the performance of correctly stacked S-SDMs alongside macroecological models.
Berberich, G., Klimetzek, D., Wöhler, C., Grumpe, A.
Statistical correlation between red wood ant sites and tectonically active fault structures
2014 Mitt. dtsch. Ges. allg. ang. Ent, volume: 19, pages: 45 - 50
Hartig, F., Dislich, C., Wiegand, T., Huth, A.
Technical Note: Approximate bayesian parameterization of a process-based tropical forest model
2014 Biogeosciences, volume: 11, pages: 1261 - 1272

Abstract Inverse parameter estimation of process-based models is a long-standing problem in many scientific disciplines. A key question for inverse parameter estimation is how to define the metric that quantifies how well model predictions fit to the data. This metric can be expressed by general cost or objective functions, but statistical inversion methods require a particular metric, the probability of observing the data given the model parameters, known as the likelihood. For technical and computational reasons, likelihoods for process-based stochastic models are usually based on general assumptions about variability in the observed data, and not on the stochasticity generated by the model. Only in recent years have new methods become available that allow the generation of likelihoods directly from stochastic simulations. Previous applications of these approximate Bayesian methods have concentrated on relatively simple models. Here, we report on the application of a simulation-based likelihood approximation for FORMIND, a parameter-rich individual-based model of tropical forest dynamics. We show that approximate Bayesian inference, based on a parametric likelihood approximation placed in a conventional Markov chain Monte Carlo (MCMC) sampler, performs well in retrieving known parameter values from virtual inventory data generated by the forest model. We analyze the results of the parameter estimation, examine its sensitivity to the choice and aggregation of model outputs and observed data (summary statistics), and demonstrate the application of this method by fitting the FORMIND model to field data from an Ecuadorian tropical forest. Finally, we discuss how this approach differs from approximate Bayesian computation (ABC), another method commonly used to generate simulation-based likelihood approximations. Our results demonstrate that simulation-based inference, which offers considerable conceptual advantages over more traditional methods for inverse parameter estimation, can be successfully applied to process-based models of high complexity. The methodology is particularly suitable for heterogeneous and complex data structures and can easily be adjusted to other model types, including most stochastic population and individual-based models. Our study therefore provides a blueprint for a fairly general approach to parameter estimation of stochastic process-based models.
Dunn, D.C., Ardron, J.A., Bax, N., Bernal, P., Cleary, J., Cresswell, I., Donnelly, B., Dunstan, P., Gjerde, K., Johnson, D., Kaschner, K., Lascelles, B., Rice, J., von Nordheim, H., Wood, L., Halpin, P.N.
The Convention on Biological Diversity’s Ecologically or Biologically Significant Areas: origins, development, and current status
2014 Mar Policy

Abstract In 2008, the Convention on Biological Diversity (CBD) adopted seven criteria to identify Ecologically or Biologically Significant Areas (EBSAs) “…in need of protection, in open ocean waters and deep sea habitats”. This paper reviews the history of the development of the “EBSA process”, which was originally driven by the commitment to establish marine protected areas in areas beyond national jurisdiction, but which has since broadened to encompass the possibility of informing marine spatial planning and other activities, both within and beyond national jurisdiction. Additionally, the paper summarizes ongoing efforts through CBD regional workshops to describe EBSAs and the development of the EBSA Repository, where information on these areas is to be stored. The overlap between the EBSA criteria and biodiversity criteria suites used by various authorities in areas beyond national jurisdiction is illustrated. The EBSA process has reached a critical juncture, whereby a large percentage of the global ocean has been considered by the regional workshops, but the procedure by which these areas can be incorporated into formal management structures has not yet been fully developed. Emerging difficulties regarding the mandate to describe, identify, endorse, or adopt EBSAs, are discussed.
Hudson, L. N., Newbold, T., Contu, S., Hill, S. L. L., Lysenko, I., De Palma, A., Phillips, H. R. P., Senior, R. A., Bennett, D. J., Booth, H., Choimes, A., Correia, D. L. P., Day, J., Echeverría-Londoño, S., Garon, M., Harrison, M. L. K., Ingram, D. J., Jung, M., Kemp, V., Kirkpatrick, L., Martin, C. D., Pan, Y., White, H. J., Aben, J., Abrahamczyk, S., Adum, G. B., Aguilar-Barquero, V., Aizen, M. A., Ancrenaz, M., Arbeláez-Cortés, E., Armbrecht, I., Azhar, B., Azpiroz, A. B., Baeten, L., Báldi, A., Banks, J. E., Barlow, J., Batáry, P., Bates, A. J., Bayne, E. M., Beja, P., Berg, Å., Berry, N. J., Bicknell, J. E., Bihn, J. H., Böhning-Gaese, K., Boekhout, T., Boutin, C., Bouyer, J., Brearley, F. Q., Brito, I., Brunet, J., Buczkowski, G., Buscardo, E., Cabra-García, J., Calviño-Cancela, M., Cameron, S. A., Cancello, E. M., Carrijo, T. F., Carvalho, A. L., Castro, H., Castro-Luna, A. A., Cerda, R., Cerezo, A., Chauvat, M., Clarke, F. M., Cleary, D. F. R., Connop, S. P., D'Aniello, B., da Silva, P. G., Darvill, B., Dauber, J., Dejean, A., Diekötter, T., Dominguez-Haydar, Y., Dormann, C.F., Dumont, B., Dures, S. G., Dynesius, M., Edenius, L., Elek, Z., Entling, M. H., Farwig, N., Fayle, T. M., Felicioli, A., Felton, A. M., Ficetola, G. F., Filgueiras, B. K. C., Fonte, S. J., Fraser, L. H., Fukuda, D., Furlani, D., Ganzhorn, J. U., Garden, J. G., Gheler-Costa, C., Giordani, P., Giordano, S., Gottschalk, M. S., Goulson, D., Gove, A. D., Grogan, J., Hanley, M. E., Hanson, T., Hashim, N. R., Hawes, J. E., Hébert, C., Helden, A. J., Henden, J.-A., Hernández, L., Herzog, F., Higuera-Diaz, D., Hilje, B., Horgan, F. G., Horváth, R., Hylander, K., Isaacs-Cubides, P., Ishitani, M., Jacobs, C. T., Jaramillo, V. J., Jauker, B., Jonsell, M., Jung, T. S., Kapoor, V., Kati, V., Katovai, E., Kessler, M., Knop, E., Kolb, A., Kőrösi, Á., Lachat, T., Lantschner, V., Le Féon, V., LeBuhn, G., Légaré, J.-P., Letcher, S. G., Littlewood, N. A., López-Quintero, C. A., Louhaichi, M., Lövei, G. L., Lucas-Borja, M. E., Luja, V. H., Maeto, K., Magura, T., Mallari, N. A., Marin-Spiotta, E., Marshall, E. J. P., Martínez, E., Mayfield, M.M., Mikusinski, G., Milder, J. C., Miller, J. R., Morales, C. L., Muchane, M. N., Muchane, M., Naidoo, R., Nakamura, A., Naoe, S., Nates-Parra, G., Navarrete Gutierrez, D. A., Neuschulz, E. L., Noreika, N., Norfolk, O., Noriega, J. A., Nöske, N. M., O'Dea, N., Oduro, W., Ofori-Boateng, C., Oke, C. O., Osgathorpe, L. M., Paritsis, J., Parra-H, A., Pelegrin, N., Peres, C. A., Persson, A. S., Petanidou, T., Phalan, B., Philips, T. K., Poveda, K., Power, E. F., Presley, S. J., Proença, V., Quaranta, M., Quintero, C., Redpath-Downing, N. A., Reid, J. L., Reis, Y. T., Ribeiro, D. B., Richardson, B. A., Richardson, M. J., Robles, C. A., Römbke, J., Romero-Duque, L. P., Rosselli, L., Rossiter, S. J., Roulston, T. H., Rousseau, L., Sadler, J. P., Sáfián, S., Saldaña-Vázquez, R. A., Samnegård, U., Schüepp, C., Schweiger, O., Sedlock, J. L., Shahabuddin, G., Sheil, D., Silva, F. A. B., Slade, E. M., Smith-Pardo, A. H., Sodhi, N. S., Somarriba, E. J., Sosa, R. A., Stout, J. C., Struebig, M. J., Sung, Y.-H., Threlfall, C. G., Tonietto, R., Tóthmérész, B., Tscharntke, T., Turner, E. C., Tylianakis, J. M., Vanbergen, A. J., Vassilev, K., Verboven, H. A. F., Vergara, C. H., Vergara, P. M., Verhulst, J., Walker, T. R., Wang, Y., Watling, J. I., Wells, K., Williams, C. D., Willig, M. R., Woinarski, J. C. Z., Wolf, J. H. D., Woodcock, B. A., Yu, D. W., Zaitsev, A. S., Collen, B., Ewers, R. M., Mace, G. M., Purves, D. W., Scharlemann, J. P. W., Purvis, A.
The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts
2014 Ecol Evol, volume: 4, issue: 24, pages: 2045 - 7758

Abstract Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015.
Carvalheiro, L., Biesmeijer, J., Benadi, G., Fruend, J., Stang, M., Dormann, C. F., et al.
The potential for indirect effects between co-flowering plants via shared pollinators depends on resource abundance, accessibility and relatedness.
2014 Ecol Lett, volume: 17, pages: 1389 - 1399

2013

Benadi, G., Blüthgen, N., Hovestadt, T., Poethke, H-J.
When can plant-pollinator interactions promote plant diversity?
2013 Am Nat, volume: 182, pages: 131 - 146

Abstract In the light of rapid losses of biodiversity worldwide, it has become more important than ever to study the factors that ensure the continued existence of diverse ecological communities. Whereas the diversity-enhancing effects of antagonistic interactions are relatively well understood, much less is known about the contribution of mutualistic interactions to biodiversity maintenance. This study assesses the influence of mutualistic interactions with pollinators on the diversity of plant communities with alternative means of reproduction besides animal pollination. In contrast to a recent more general model of plant-animal mutualisms, the results of our simulations suggest that interactions with pollinators do not generally promote plant diversity, irrespective of the structure of the interaction network. Despite a potential for increased plant species richness through the positive effect of pollinators on plant birth rates, species richness was mostly negatively affected by the presence of pollinators because existing abundance asymmetries were amplified by animal pollination. Our results imply that for plant communities with alternative means of reproduction, the loss of pollinators will usually not lead to decreased diversity. However, whereas the immediate effects of pollinator loss on plant community composition may be negligible, the long-term population genetic consequences are likely to be severe.
van Oijen, M., Reyer, C., Bohn, F., Cameron, D., Deckmyn, G., Flechsig, M., Härkönen, S., Hartig, F., Huth, A., Kiviste, A., Lasch, P., Mäkalä, A., Mette, T., Minunno, F., Rammer, W.
Bayesian calibration, comparison and averaging of six forest models, using data from Scots pine stands across Europe.
2013 For. Ecol. Manage, issue: 289, pages: 255 - 268

Abstract Forest management requires prediction of forest growth, but there is no general agreement about which models best predict growth, how to quantify model parameters, and how to assess the uncertainty of model predictions. In this paper, we show how Bayesian calibration (BC), Bayesian model comparison (BMC) and Bayesian model averaging (BMA) can help address these issues. We used six models, ranging from simple parameter-sparse models to complex process-based models: 3PG, 4C, ANAFORE, BASFOR, BRIDGING and FORMIND. For each model, the initial degree of uncertainty about parameter values was expressed in a prior probability distribution. Inventory data for Scots pine on tree height and diameter, with estimates of measurement uncertainty, were assembled for twelve sites, from four countries: Austria, Belgium, Estonia and Finland. From each country, we used data from two sites of the National Forest Inventories (NFIs), and one Permanent Sample Plot (PSP). The models were calibrated using the NFI-data and tested against the PSP-data. Calibration was done both per country and for all countries simultaneously, thus yielding country-specific and generic parameter distributions. We assessed model performance by sampling from prior and posterior distributions and comparing the growth predictions of these samples to the observations at the PSPs. We found that BC reduced uncertainties strongly in all but the most complex model. Surprisingly, country-specific BC did not lead to clearly better within-country predictions than generic BC. BMC identified the BRIDGING model, which is of intermediate complexity, as the most plausible model before calibration, with 4C taking its place after calibration. In this BMC, model plausibility was quantified as the relative probability of a model being correct given the information in the PSP-data. We discuss how the method of model initialisation affects model performance. Finally, we show how BMA affords a robust way of predicting forest growth that accounts for both parametric and model structural uncertainty.
Fründ, J., Dormann, C. F., Holzschuh, A., Tscharntke, T.
Bee diversity effects on pollination depend on functional complementarity and niche shifts
2013 Ecology, volume: 94, issue: 9, pages: 2042 - 2054

Abstract Biodiversity is important for many ecosystem processes. Global declines in pollinator diversity and abundance have been recognized, raising concerns about a pollination crisis of crops and wild plants. However, experimental evidence for effects of pollinator species diversity on plant reproduction is extremely scarce. We established communities with 1–5 bee species to test how seed production of a plant community is determined by bee diversity. Higher bee diversity resulted in higher seed production, but the strongest difference was observed for one compared to more than one bee species. Functional complementarity among bee species had a far higher explanatory power than bee diversity, suggesting that additional bee species only beneﬁt pollination when they increase coverage of functional niches. In our experiment, complementarity was driven by differences in ﬂower and temperature preferences. Interspeciﬁc interactions among bee species contributed to realized functional complemen- tarity, as bees reduced interspeciﬁc overlap by shifting to alternative ﬂowers in the presence of other species. This increased the number of plant species visited by a bee community and demonstrates a new mechanism for a biodiversity–function relationship (‘‘interactive complementarity’’). In conclusion, our results highlight both the importance of bee functional diversity for the reproduction of plant communities and the need to identify complementarity traits for accurately predicting pollination services by different bee communities.
Dormann, C. F., Elith, J., Bacher, S., Buchmann, C. M., Carl, G., Carré, G., Diekötter, T., Marquéz, J. R. G., Gruber, B., Lafourcade, B., Leitão, P. J., Münkemüller, T., McClean, C., Osborne, P., Reineking, B., Schröder, B., Skidmore, A., Zurell, D., Lautenbach, S.
Collinearity: a review of methods to deal with it and a simulation study evaluating their performance.
2013 Ecography, issue: 36, pages: 27 - 46
Benadi, G., Blüthgen, N., Hovestadt, T., Poethke, H.-J.
Contrasting specialization-stability relationships in plant-animal mutualistic systems.
2013 Ecol Model, volume: 258, issue: 10, pages: 65 - 73

Abstract Specialization has often been suggested as one of the main factors influencing the stability of ecological systems at the population and community level. Generally, highly specialized systems are believed to be the most sensitive toward disturbances, as the dependence of specialized species on the availability of particular resources or partner species is greatest. The flip side of specialization is, however, that it reduces the intensity of interspecific competition and thus the risk of extinction through competitive exclusion. Moreover, since ecological stability is a highly ambiguous concept, general statements about the relationship between specialization and stability cannot be made based on a single stability criterion. In this study, we examine the relationship between specialization and stability in plant–animal mutualistic systems using a population dynamic model with two species in each group. We compare results for four different stability criteria, both for a general type of plant–animal mutualism and specifically for a plant–pollinator system. Contrary to previous studies which concluded that specialization increases system vulnerability to disturbances, we find that positive, negative and unimodal relationships are possible depending on the stability criterion applied and the characteristics of species interactions. Our results call for further investigations of the consequences of ecological specialization, and emphasize the special properties of pollination mutualisms.
Holzschuh, A., Dormann, C. F., Tscharntke, T., Steffan-Dewenter, I.
Mass-flowering crops enhance wild bee abundance.
2013 Oecologia, volume: 172, pages: 477 - 484

Abstract Although agricultural habitats can provide enormous amounts of food resources for pollinator species, links between agricultural and (semi-)natural habitats through dispersal and foraging movements have hardly been studied. In 67 study sites, we assessed the interactions between mass-flowering oilseed rape fields and semi-natural grasslands at different spatial scales, and their effects on the number of brood cells of a solitary cavity-nesting bee. The probability that the bee Osmia bicornis colonized trap nests in oilseed rape fields increased from 12 to 59 % when grassland was nearby, compared to fields isolated from grassland. In grasslands, the number of brood cells of O. bicornis in trap nests was 55 % higher when adjacent to oilseed rape compared to isolated grasslands. The percentage of oilseed rape pollen in the larval food was higher in oilseed rape fields and grasslands adjacent to oilseed rape than in isolated grasslands. In both oilseed rape fields and grasslands, the number of brood cells was positively correlated with the percentage of oilseed rape pollen in the larval food. We show that mass-flowering agricultural habitats—even when they are intensively managed—can strongly enhance the abundance of a solitary bee species nesting in nearby semi-natural habitats. Our results suggest that positive effects of agricultural habitats have been underestimated and might be very common (at least) for generalist species in landscapes consisting of a mixture of agricultural and semi-natural habitats. These effects might also have—so far overlooked—implications for interspecific competition and mutualistic interactions in semi-natural habitats.
Taubert, F., Hartig, F., Dobner, H.-J., Huth, A.
On the challenge of fitting tree size distributions in ecology.
2013 Plos One, issue: 8, page: e58036

Abstract Patterns that resemble strongly skewed size distributions are frequently observed in ecology. A typical example represents tree size distributions of stem diameters. Empirical tests of ecological theories predicting their parameters have been conducted, but the results are difficult to interpret because the statistical methods that are applied to fit such decaying size distributions vary. In addition, binning of field data as well as measurement errors might potentially bias parameter estimates. Here, we compare three different methods for parameter estimation – the common maximum likelihood estimation (MLE) and two modified types of MLE correcting for binning of observations or random measurement errors. We test whether three typical frequency distributions, namely the power-law, negative exponential and Weibull distribution can be precisely identified, and how parameter estimates are biased when observations are additionally either binned or contain measurement error. We show that uncorrected MLE already loses the ability to discern functional form and parameters at relatively small levels of uncertainties. The modified MLE methods that consider such uncertainties (either binning or measurement error) are comparatively much more robust. We conclude that it is important to reduce binning of observations, if possible, and to quantify observation accuracy in empirical studies for fitting strongly skewed size distributions. In general, modified MLE methods that correct binning or measurement errors can be applied to ensure reliable results.
Batáry, P., Sutcliffe, L., Dormann, C. F., Tscharntke, T.
Organic farming favours insect-pollinated over non-insect pollinated forbs in meadows and wheat fields
2013 Plos One, volume: 8

Abstract The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators.
Schymanski, S. J., Dormann, C. F., Cabral, J. S., Chuine, I., Graham, C. H., Hartig, F., Kearney, M. R., Morin, X., Römermann, C., Schröder, B., Singer, A.
Process, correlation and parameter fitting in species distribution models: a response to Kriticos et al.
2013 J Biogeogr, issue: 40, pages: 611 - 613

Abstract In a recent article (Dormann et al., 2012, Journal of Biogeography, 39, 2119–2131), we compared different approaches to species distribution modelling and depicted modelling approaches along an axis from purely ‘correlative’ to ‘forward processbased’ models. In their correspondence, Kriticos et al. (2013, Journal of Biogeography, doi:10.1111/j.1365-2699.2012.02791.x) challenge this view, claiming that our continuum representation neglects differences among models and does not consider the ability of fitted process-based models to combine the advantages of both processbased and correlative modelling approaches. Here we clarify that the continuum view resulted from recognition of the manifold differences between models. We also reinforce the point that the current trend towards combining different modelling approaches may lead not only to the desired combination of the advantages but also to the accumulation of the disadvantages of those approaches. This point has not been made sufficiently clear previously
Kraan, C., Aarts, G., Piersma, T., Dormann, C. F.
Temporal variability of ecological niches: a study on intertidal macrobenthic fauna
2013 Oikos, issue: 122, pages: 754 - 760

Abstract The determination of temporal niche dynamics under field conditions is an important component of a species’ ecology. Recent developments in niche mapping, and the possibility to account for spatial autocorrelation in species distributions, hold promise for the statistical approach explored here. Using species counts from a landscape-scale benthic monitoring programme in the western Dutch Wadden Sea during 1997–2005 in combination with sediment characteristics and tidal height as explanatory variables, we statistically derive realised niches for two bivalves, two crustaceans and three polychaetes, encompassing predators, suspension and bottom feeding functional groups. Unsurprisingly, realized niches varied considerably between species. Intraspecific temporal variation was assessed as overlap between the year-specific niche and the overall mean niche, and this analysis revealed considerable variation between years. The main functional groups represented by these species showed idiosyncratic and wide variability through the study period. There were no strong associations between niche characteristics and mean abundance or body size. Our assessment of intraspecific niche variability has ramifications for species distribution models in general and offers advances from previous methods. 1) By assessing species’ realized niches in the multivariate environmental space, analyses are independent from the relative availability of particular environments. Predicted realized niches present differences between years, rather than annual differences in environmental conditions. 2) Using spatially explicit models to predict species habitat preferences provide more precise and unbiased estimates of species–environment relationships. 3) Current niche models assume constant niches, whereas we illustrate how much these can vary over only a few generations. This emphasizes the potentially limited scope of global change studies with forecasts based on single-time species distribution snapshots.
Wisz, M. S., Pottier, J., Kissling, W. D., Pellissier, L., Lenoir, J., Damgaard, C. F., Dormann, C. F., Forchhammer, M. C., Gryntes, J. A., Guisan, A., Heikkinen, R. K., Høye, T. T., Kühn, I., Luoto, M., Maiorano, L., Nilsson, M. C., Normand, S., Öckinger, E., Schmidt, N. M., Termansen, M., Timmermann, A., Wardle, D. A., Aastrup, P., Svenning, J. -C.
The role of biotic interactions in shaping distributions and realised assemblages of species: implications for species distribution modelling
2013 Biol Rev, issue: 88, pages: 15 - 30

Abstract Predicting which species will occur together in the future, and where, remains one of the greatest challenges in ecology, and requires a sound understanding of how the abiotic and biotic environments interact with dispersal processes and history across scales. Biotic interactions and their dynamics influence species’ relationships to climate, and this also has important implications for predicting future distributions of species. It is already well accepted that biotic interactions shape species’ spatial distributions at local spatial extents, but the role of these interactions beyond local extents (e.g. 10 km2 to global extents) are usually dismissed as unimportant. In this review we consolidate evidence for how biotic interactions shape species distributions beyond local extents and review methods for integrating biotic interactions into species distribution modelling tools. Drawing upon evidence from contemporary and palaeoecological studies of individual species ranges, functional groups, and species richness patterns, we show that biotic interactions have clearly left their mark on species distributions and realised assemblages of species across all spatial extents. We demonstrate this with examples from within and across trophic groups. A range of species distribution modelling tools is available to quantify species environmental relationships and predict species occurrence, such as: (i) integrating pairwise

2012

García Márquez, J. R., Dormann, C. F., Sommer, J. H., Schmidt, M., Thiombiano, A., Da, S. S., Chatelain, C., Dressler, S., Barthlott, W.
A methodological framework to quantify the spatial quality of biological databases
2012 Biodiversity and Ecology, issue: 4, pages: 25 - 39

Abstract The basic information necessary for biogeographical analysis is the geographical location appended to the data contained in biological databases. Reliability of analyses thus crucially depends on the quality of the spatial information available. In the present study we build on a database of vascular plants of West Africa (Ivory Coast, Burkina Faso, Benin), containing 53,205 georeferenced observations distributed over 2,931 collection localities. We propose a methodology to quantify the quality of the database through a series of spatial analyses of spatial configuration of the collection localities, their spatial and environmental bias and inventory com-pleteness. The spatial configuration of the database followed a highly clustered pattern and was strongly biased with respect to the dis-tance to cities, the coast, rivers, roads and protected areas. The same biased pattern was found in relation to several environmental fac-tors. Inventory completeness was calculated by estimating the total number of species based on two non-parametric estimates (first-order Jackknife and Bootstrap) and at different grid cell sizes. At the highest resolution (100 km²) only 5.5% of the cells contained a near-complete (> 80% of Jackknife estimates) species inventory. The percentage of near-complete cells increased as the resolution of analysis decreased. Results of all analyses were integrated into a new index (Gap Selection Index) that serves to guiding future field work campaigns and as cautionary criterion for the uncertainties related to biogeographical application based on the current database.
Blüthgen, N., Dormann, C. F., Prati, D., Klaus, V. H., Kleinebecker, T., Hölzel, N., Alt, F., Boch, S., Sonja, G., Hemp, A., Müller, J., Nieschulze, J., Renner, S. C., Schöning, I., Schumacher, U., Socher, S. A., Wells, K., Birkhofer, K., Buscot, F., Oelmann, Y., Rothenwöhrer, C., Scherber, C., Tscharntke, T., Weiner, C. N., Fischer, M., Kalko, E. K. V., Linsenmair, K. E., Schulze, E. -D., Weisser, W. W.
A quantitative index of land-use intensity in grasslands: Integrating mowing, grazing and fertilization
2012 Basic Appl Ecol, issue: 13, pages: 207 - 220

Abstract Land use is increasingly recognized as a major driver of biodiversity and ecosystem functioning in many current research projects. In grasslands, land use is often classified by categorical descriptors such as pastures versus meadows or fertilized versus unfertilized sites. However, to account for the quantitative variation of multiple land-use types in heterogeneous landscapes, a quantitative, continuous index of land-use intensity (LUI) is desirable. Here we define such a compound,
Schnitzler, J., Dormann, C. F., Graham, C. H., Schiffers, K., Linder, H. P.
Climatic-niche evolution and species diversification in the Cape flora, South Africa.
2012 J Biogeogr, volume: 39, pages: 2201 - 2211

Abstract Aim To evaluate the evolutionary dynamics of the ecological niche by quantifying the modes and rates of ecological niche evolution (with a particular focus on climatic parameters) and species diversification. Location Greater Cape Floristic Region, southern Africa. Methods Using the genus Babiana (Iridaceae) from the Cape flora, South Africa, we study the evolutionary dynamics of the ecological niche, which includes a characterization of the ecological niche, an assessment of phylogenetic signal, comparisons of different macroevolutionary models, and the estimation of rates of niche evolution (and their variation within and between clades) and lineage diversification, while accounting for phylogenetic uncertainty. Results A principal components analysis (PCA) identified mean annual precipitation and mean annual temperature as the most important climatic determinants differentiating species within Babiana. All parameters show significant phylogenetic signal, and the best-fit model of evolution is the Ornstein– Uhlenbeck process with two distinct precipitation optima for two neighbouring biomes: the Fynbos and the Succulent Karoo. Evolutionary rates of climatic niches vary by more than an order of magnitude over the phylogeny, and rates of niche evolution and lineage diversification are both higher in the Fynbos biome than in the Succulent Karoo. Main conclusions Our results show a possible link between rates of climatic niche evolution and rates of species diversification, indicating that rates of niche evolution might be driving diversification rates.
Hartig, F., Dyke, J., Hickler, T., Higgins, S. I., O'Hara, R. B., Scheiter, S., Huth, A.
Connecting dynamic vegetation models to data - an inverse perspective.
2012 J Biogeogr, issue: 39, pages: 2240 - 2252

Abstract Dynamic vegetation models provide process-based explanations of the dynamics and the distribution of plant ecosystems. They offer significant advantages over static, correlative modelling approaches, particularly for ecosystems that are outside their equilibrium due to global change or climate change. A persistent problem, however, is their parameterization. Parameters and processes of dynamic vegetation models (DVMs) are traditionally determined independently of the model, while model outputs are compared to empirical data for validation and informal model comparison only. But field data for such independent estimates of parameters and processes are often difficult to obtain, and the desire to include better descriptions of processes such as biotic interactions, dispersal, phenotypic plasticity and evolution in future vegetation models aggravates limitations related to the current parameterization paradigm. In this paper, we discuss the use of Bayesian methods to bridge this gap. We explain how Bayesian methods allow direct estimates of parameters and processes, encoded in prior distributions, to be combined with inverse estimates, encoded in likelihood functions. The combination of direct and inverse estimation of parameters and processes allows a much wider range of vegetation data to be used simultaneously, including vegetation inventories, species traits, species distributions, remote sensing, eddy flux measurements and palaeorecords. The possible reduction of uncertainty regarding structure, parameters and predictions of DVMs may not only foster scientific progress, but will also increase the relevance of these models for policy advice.
Dormann, C. F., Schymanski, S. J., Cabral, J., Chuine, I., Graham, C., Hartig, F., Kearney, M., Morin, X., Römermann, C., Schröder, B., Singer, A
Correlation and process in species distribution models: bridging a dichotomy
2012 J Biogeogr, volume: 39, pages: 2119 - 2131
Shataee, S., Kalb, S., Fallah, A., Pelz, D.
Forest attribute imputation using machine-learning methods and ASTER data: comparison of k-NN,SVR and random forest regression algorithms
2012 International Journal of Remote Sensing, volume: 33, issue: 19, pages: 6254 - 6280

Abstract In a small case study of mixed hardwood Hyrcanian forests of Iran, three non-parametric methods, namely k-nearest neighbour (k-NN), support vector machine regression (SVR) and tree regression based on random forest (RF), were used in plot-level estimation of volume/ha, basal area/ha and stems/ha using field inventory and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. Relevant pre-processing and processing steps were applied to the ASTER data for geometric and atmospheric correction and for enhancing quantitative forest parameters. After collecting terrestrial information on trees in the 101 samples, the volume, basal area and tree number per hectare were calculated in each plot. In the k-NN implementation using different distance measures and k, the cross-validation method was used to find the best distance measure and optimal k. In SVR, the best regularized parameters of four kernel types were obtained using leave-one-out cross-validation. RF was implemented using a bootstrap learning method with regularized parameters for decision tree model and stopping. The validity of performances was examined using unused test samples by absolute and relative root mean square error (RMSE) and bias metrics. In volume/ha estimation, the results showed that all the three algorithms had similar performances. However, SVR and RF produced better results than k-NN with relative RMSE values of 28.54, 25.86 and 26.86 (m3 ha–1), respectively, using k-NN, SVR and RF algorithms, but RF could generate unbiased estimation. In basal area/ha and stems/ha estimation, the implementation results of RF showed that RF was slightly superior in relative RMSE (18.39, 20.64) to SVR (19.35, 22.09) and k-NN (20.20, 21.53), but k-NN could generate unbiased estimation compared with the other two algorithms used.
Schurr, F.M., Pagel, J., Cabral, J.S., Groeneveld, J., Bykova, O., Hara, R. B. O., Hartig, F., Kissling, W. D., Linder, H.P., Midgley, G.F., Schröder, B., Singer, A., Zimmermann, N.E.
How to understand species' niches and range dynamics: a demographic research agenda for biogeography
2012 J Biogeogr
Kühn, I., Dormann, C. F.
Less than eight (and a half) misconceptions of spatial analysis
2012 J Biogeogr, issue: 39, pages: 995 - 1003

Abstract Spatial analyses are indispensable analytical tools in biogeography and macroecology. In a recent Guest Editorial, Hawkins (Journal of Biogeography, 2012, 39, 1–9) raised several issues related to spatial analyses. While we concur with some points, we here clarify those confounding (1) spatial trends and spatial autocorrelation, and (2) spatial autocorrelation in the response variable and in the residuals. We argue that recognizing spatial autocorrelation in statistical modelling is not only a crucial step in model diagnostics, but that disregarding it is essentially wrong.
Lautenbach, S., Maes, J., Kattwinkel, M., Seppelt, R., Strauch, M., Scholz, M., Schulz-Zunkel, C., Volk, M., Weinert, J., Dormann, C. F.
Mapping water quality-related ecosystem services: concepts and applications for nitrogen retention and pesticide risk reduction
2012 International Journal of Biodiversity Science, Ecosystem Services & Management, volume: 8, pages: 35 - 49

Abstract One of the challenges of using the ecosystem service (ES) framework in the context of planning and decision support is the question of how to map these services in an appropriate way. For water quality-related ESs, this implies a movement from the display of classical water quality indicators towards the mapping of the service itself. We explore the potential of mapping such water quality-related ESs based on three case studies focusing on different aspects of these services: (1) a European case study on pesticides, (2) a multi-scale German case study on nitrogen retention and (3) a more local case study on nitrogen retention in the Elbe floodplain (Lödderitzer Forst). All these studies show a high spatial variation of the results that can be depicted in maps of ES supply. This allows an identification of areas in which nitrogen retention is highest or which areas face the highest ecological risk due to pesticides. The multi-scale case study shows how the level of detail of the results varies with model resolution – a hierarchical approach to environmental and river basin management seems useful, because it allows the planners to determine scale-specific environmental problems and implement specific measures for the different planning levels.
Bijleveld, A.I., van Gils, J.A., van der Meer, J., Dekinga, A., Kraan, C., van der Veer, H.W., Piersma, T.
Maximum power for monitoring programmes: optimising sampling designs for multiple monitoring objectives.
2012 Methods in Ecology & Evolution, issue: 3, pages: 526 - 536

Abstract Summary 1. Spatial data on animal abundance underpin sound conservation and management advice. The expense of monitoring programs to determine species distributions and estimates of population sizes often limits sample size. For maximum effectiveness at minimal costs, optimisations of such monitoring efforts are critical. A monitoring programme can have multiple objectives with conflicting demands on the optimal sampling design. Here we develop an optimal sampling design for monitoring programmes with such conflicting objectives. 2. We distinguished three possible objectives: (1) estimation of temporal changes and spatial differences in abundance and (2) mapping, i.e. prediction of abundances at unsampled locations. Mapping abundances requires model-based analyses using autocorrelation models. Such analyses are as good as the model fits the data, therefore, an additional objective was (3) accurately estimating autocorrelation model parameters. 3. To compare sampling designs we used the following criteria: (1) the minimum detectable difference in mean between two time periods or two areas, (2) the mean prediction error, and (3) the estimation bias of autocorrelation parameters. Using Monte Carlo simulations we compared five common sampling designs with respect to these criteria at four levels of – naturally occurring – spatial autocorrelation. 4. The optimal sampling designs for objectives (1) and (2) was grid sampling and for objective (3) transect sampling with multiple samples per station and grid sampling with random replacements. The optimal sampling design that catered best for all three objectives combined was grid sampling with a number of random samples placed on gridlines. This, at 0.5 km intervals between grid sampling-stations, is the optimal sampling design we recommend for the Wadden Sea intertidal flats. 7 5. Syntheses and applications. Grid sampling with additional random sampling is considered an accurate and powerful tool with the largest effectiveness/cost-ratio for monitoring programmes that allows for: (1) estimates of population sizes, (2) monitoring of population trends, (3) comparisons of populations/trends between years or areas, (4) modelling autocorrelation, (5) mapping of species distributions and (6) further understanding of species distribution processes.
Gruber, B., Evans, D., Henle, K., Bauch, B., Schmeller, D. J., Dziock, D., Henry, P. -Y., Szabolcs, L., Margules, C., Dormann, C. F.
Mind the gap – How well does Natura 2000 cover species of European interest?
2012 J Nat Conserv, issue: 3, pages: 45 - 63

Abstract Setting aside protected areas is widely recognized as one of the most effective measures to prevent species from extinction. Accordingly, there has been a tremendous effort by governments worldwide to establish protected areas, resulting in over 100,000 sites, which are set aside, to achieve the 10% target proposed at the Fourth World Park Congress in 1992 in Caracas. The main effort of the European Union to achieve this target is the Natura 2000 network of protected areas, comprising over 25,000 sites representing 18% of the area of the 27 Member States of the European Union. The designation of Natura 2000 sites was based on species and habitats listed in the Annexes of the Habitats and Birds Directive. The effectiveness of the selection process and the resulting Natura 2000 network has often been questioned as each country made its designations largely independently and in most cases without considering the theories of optimal
Halbig, P., Delb, H., Henke, L., Wagenhoff, E., Klimetzek, D.
Monitoring und Gefahrenanalyse des Pinienprozessionsspinners, 'Thaumetopoeqa pityocampa' (DEN. & SCHIFF. 1775) ('Lep., Notodontidae'), für die Oberrheinebene.
2012 Mitt. dtsch. Ges. allg. ang. Ent, volume: 18, pages: 405 - 407
Johst, K., Hartig, F., Drechsler, M.
Offsetting Policies for Biodiversity Conservation: The Need for Compensating Habitat Relocation.
2012 Elsevier, issue: 25, pages: 413 - 430

Abstract To halt biodiversity loss, market-based conservation policies known as biodiversity offsetting are increasingly implemented in developed countries. These policies allow the destruction of natural habitats if new habitat of equal quality has been created elsewhere. Yet, even at constant total habitat area, patch relocations can be detrimental for species. Using an analytical formula for metapopulation viability, we provide understanding and novel insights into the interplay between the landscape attributes patch number, connectivity, and level of patch turnover. We show that both landscape and species characteristics must be considered to ensure that biodiversity offsetting is effective and derive guidelines for the design of such policies.
Marion, G., McInerny, G.J., Pagel, J., Catterall, S., Cook, A.R., Hartig, F., O'Hara, R.B.
Parameter and uncertainty estimation for process-oriented population and distribution models: data, statistics and the niche.
2012 J Biogeogr, issue: 39, pages: 2225 - 2239

Abstract The spatial distribution of a species is determined by dynamic processes such as reproduction, mortality and dispersal. Conventional static species distribution models (SDMs) do not incorporate these processes explicitly. This limits their applicability, particularly for non-equilibrium situations such as invasions or climate change. In this paper we show how dynamic SDMs can be formulated and fitted to data within a Bayesian framework. Our focus is on discrete state-space Markov process models which provide a flexible framework to account for stochasticity in key demographic processes, including dispersal, growth and competition. We show how to construct likelihood functions for such models (both discrete and continuous time versions) and how these can be combined with suitable observation models to conduct Bayesian parameter inference using computational techniques such as Markov chain Monte Carlo. We illustrate the current state-of-the-art with three contrasting examples using both simulated and empirical data. The use of simulated data allows the robustness of the methods to be tested with respect to deficiencies in both data and model. These examples show how mechanistic understanding of the processes that determine distribution and abundance can be combined with different sources of information at a range of spatial and temporal scales. Application of such techniques will enable more reliable inference and projections, e.g. under future climate change scenarios than is possible with purely correlative approaches. Conversely, confronting such process-oriented niche models with abundance and distribution data will test current understanding and may ultimately feedback to improve underlying ecological theory.
Benadi, G., Nico, B., Thomas, H., Poethke, H.-J.
Population Dynamics of Plant and Pollinator Communities: Stability Reconsidered
2012 American Naturalist, volume: 179, issue: 2, pages: 157 - 168

Abstract Plant-pollinator networks are systems of outstanding ecological and economic importance. A particularly intriguing aspect of these systems is their high diversity. However, earlier studies have concluded that the specific mechanisms of plant-pollinator interactions are destabilizing and should lead to a loss of diversity. Here we present a mechanistic model of plant and pollinator population dynamics with the ability to represent a broad spectrum of interaction structures. Using this model, we examined the influence of pollinators on the stability of a plant community and the relationship between pollinator specialization and stability. In accordance with earlier work, our results show that plant-pollinator interactions may severely destabilize plant coexistence, regardless of the degree of pollinator specialization. However, if plant niche differentiation, a classical stabilizing mechanism, is sufficiently strong to overcome the minority disadvantage with respect to pollination, interactions with pollinators may even increase the stability of a plant community. In addition to plant niche differentiation, the relationship between specialization and stability depends on a number of parameters that affect pollinator growth rates. Our results highlight the complex effects of this particular type of mutualism on community stability and call for further investigations of the mechanisms of diversity maintenance in plant-pollinator systems.
Saleem, M., Fetzer, I., Dormann, C. F., Harms, H., Chatzinotas, A.
Predator richness increases the effect of prey diversity on prey yield.
2012 Nat Commun, issue: 3, page: 1305

Abstract Positive biodiversity-ecosystem functioning relationships are generally attributed to two mechanisms: complementarity and selection. These mechanisms have been primarily examined using plant communities, whereas bacterial communities remain largely unexplored. Moreover, it remains uncertain how predation by single or multiple predators affects these mechanisms. Here using 465 bacterial microcosms, we show that multiple predation by protists results in positive bacterial diversity effects on bacterial yields (colonyforming units) possibly due to an increased complementarity and evenness among bacterial species. By mathematically partitioning the biodiversity effects, we demonstrate that competitive interactions in diverse communities are reduced and the growth of subdominant species is enhanced. We envisage that, including diversity gradients at other trophic levels, in biodiversity-ecosystem functioning research is a key to understanding and managing ecosystem processes. Such level of manipulation can be achieved best in microbial model systems, which are powerful tools for fundamental hypothesis-driven experiments and the investigation of general ecological theories. DOI: 10.1038/ncomms2287 1
Lautenbach, S., Seppelt, R., Liebscher, J., Dormann, C. F.
Spatial and temporal trends of global pollination benefit
2012 Plos One, volume: 7, pages: 1 - 21

Abstract Pollination is a well-studied and at the same time a threatened ecosystem service. A significant part of global crop production depends on or profits from pollination by animals. Using detailed information on global crop yields of 60 pollination dependent or profiting crops, we provide a map of global pollination benefits on a 5′ by 5′ latitude-longitude grid. The current spatial pattern of pollination benefits is only partly correlated with climate variables and the distribution of cropland. The resulting map of pollination benefits identifies hot spots of pollination benefits at sufficient detail to guide political decisions on where to protect pollination services by investing in structural diversity of land use. Additionally, we investigated the vulnerability of the national economies with respect to potential decline of pollination services as the portion of the (agricultural) economy depending on pollination benefits. While the general dependency of the agricultural economy on pollination seems to be stable from 1993 until 2009, we see increases in producer prices for pollination dependent crops, which we interpret as an early warning signal for a conflict between pollination service and other land uses at the global scale. Our spatially explicit analysis of global pollination benefit points to hot spots for the generation of pollination benefits and can serve as a base for further planning of land use, protection sites and agricultural policies for maintaining pollination services.

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Schleuning, M., Fründ, J., Klein, A.-M., Abrahamczyk, S., Alarcón, R., Albrecht, M., Andersson, G. K. S., Bazarian, S., Böhning-Gaese, K., Bommarco, R., Dalsgaard, B., Dehling, D. M., Gotlieb, A., Hagen, M., Hickler, T., Holzschuh, A., Kaiser-Bunbury, C. N., Kreft, H., Morris, R. J., Sandel, B., Sutherland, W. J., Svenning, J. -C., Tscharntke, T., Watts, S., Weiner, C. N., Werner, M., Williams, N.M., Winqvist, C., Dormann, C. F., Blüthgen, N.
Specialization of mutualistic interaction networks decreases toward tropical latitudes
2012 Curr Biol, volume: 22, pages: 1 - 7

Abstract Species-rich tropical communities are expected to be more specialized than their temperate counterparts [1–3]. Several studies have reported increasing biotic specialization toward the tropics [4–7], whereas others have not found latitudinal trends once accounting for sampling bias [8, 9] or differences in plant diversity [10, 11]. Thus, the direction of the latitudinal specialization gradient remains contentious. With an unprecedented global data set, we investigated how biotic specialization between plants and animal pollinators or seed dispersers is associated with latitude, past and contemporary climate, and plant diversity. We show that in contrast to expectation, biotic specialization of mutualistic networks is significantly lower at tropical than at temperate latitudes. Specialization was more closely related to contemporary climate than to past climate stability, suggesting that current conditions have a stronger effect on biotic specialization than historical community stability. Biotic specialization decreased with increasing local and regional plant diversity. This suggests that high specialization of mutualistic interactions is a response of pollinators and seed dispersers to low plant diversity. This could explain why the latitudinal specialization gradient is reversed relative to the latitudinal diversity gradient. Low mutualistic network specialization in the tropics suggests higher tolerance against extinctions in tropical than in temperate communities.
Blitzer, E. J., Dormann, C. F., Holzschuh, A., Klein, A. -M., Rand, T. A., Tscharntke, T.
Spillover of functionally important organisms between managed and natural habitats
2012 Agr Ecosyst Environ, volume: 146, pages: 34 - 43

Abstract Land-use intensification has led to a landscape mosaic that juxtaposes human-managed and natural areas. In such human-dominated and heterogeneous landscapes, spillover across habitat types, especially in systems that differ in resource availability, may be an important ecological process structuring communities. While there is much evidence for spillover from natural habitats to managed areas, little attention has been given to flow in the opposite direction. This paper synthesizes studies published to date from five functionally important trophic groups, herbivores, pathogens, pollinators, predators, and seed dispersers, and discusses evidence for spillover from managed to natural systems in all five groups. For each of the five focal groups, studies in the natural to managed direction are common, often with multiple review articles on each subject which document dozens of examples. In contrast, the number of studies which examine movement in the managed to natural direction is generally less than five studies per trophic group. These findings suggest that spillover in the managed to natural direction has been largely underestimated. As habitat modification continues, resulting in increasingly fragmented landscapes, the likelihood and size of any spillover effect will only increase.
Addo-Danso, S.D., Bosu, P.P., Nkrumah, E.E., Pelz, D.R., Coke, S.A., Adu-Bredu1, S.
Survival and growth of 'Nauclea diderrichii' and 'Pericopsis elata' in monoculture and mixed-species plots in Ghana
2012 Journal of Tropical Forest Science 24, volume: 24, issue: 1, pages: 37 - 45

Abstract 'Nauclea diderrichii' and 'Pericopsis elata' are valuable timber species which are attacked by 'Orygmophora mediofoveata' and 'Lamprosema lateritialis' respectively in plantations. This study was carried out to evaluate the effects of mixed-species planting on survival and growth of these species. The two species (N. diderrichii and P. elata) and three other species (Albizia adianthifolia, Terminalia superba and Tetrapleura tetraptera) were planted in various mixtures. Their survival and growth were monitored for 60 months. Generally, survival and growth performance of 'P. elata' and 'N. diderrichii' were not affected by planting schemes. Trees of both species grew as well in monocultures as they did in mixed stands. Block effect had impact on survival of 'P. elata' and height growth of 'N. diderrichii'. This indicated the importance of local site variability on survival and growth of the two species. While no significant differences in survival and growth were recorded between monoculture and mixed stands of the two timber species, the socio-economic and ecological advantages of mixtures provide sufficient justification to encourage mixed-species plantations.
Kissling, W. D., Dormann, C. F., Groenefeld, J., Hickler, T., Kühn, I., McInerny, G. J., Monotya, J. M., Römermann, C., Schiffers, K., Schurr, F. M., Singer, A., Svenning, J. -C., Zimmermann, N. E., O'Hara, R. B.
Towards novel approaches to modelling biotic interactions in multispecies assemblages at large spatial extents.
2012 J Biogeogr, volume: 39, pages: 2163 - 2178

Abstract ABSTRACT Aim Biotic interactions – within guilds or across trophic levels – have widely been ignored in species distribution models (SDMs). This synthesis outlines the development of ‘species interaction distribution models’ (SIDMs), which aim to incorporate multispecies interactions at large spatial extents using interaction matrices. Location Local to global. Methods We review recent approaches for extending classical SDMs to incorporate biotic interactions, and identify some methodological and conceptual limitations. To illustrate possible directions for conceptual advancement we explore three principal ways of modelling multispecies interactions using interaction matrices: simple qualitative linkages between species, quantitative interaction coefficients reflecting interaction strengths, and interactions mediated by interaction currencies. We explain methodological advancements for static interaction data and multispecies time series, and outline methods to reduce complexity when modelling multispecies interactions. Results Classical SDMs ignore biotic interactions and recent SDM extensions only include the unidirectional influence of one or a few species. However, novel methods using error matrices in multivariate regression models allow interactions between multiple species to be modelled explicitly with spatial co-occurrence data. If time series are available, multivariate versions of population dynamic models can be applied that account for the effects and relative importance of species interactions and environmental drivers. These methods need to be extended by incorporating the non-stationarity in interaction coefficients across space and time, and are challenged by the limited empirical knowledge on spatiotemporal variation in the existence and strength of species interactions. Model complexity may be reduced by: (1) using prior ecological knowledge to set a subset of interaction coefficients to zero, (2) modelling guilds and functional groups rather than individual species, and (3) modelling interaction currencies and species’ effect and response traits. Main conclusions There is great potential for developing novel approaches that incorporate multispecies interactions into the projection of species distributions and community structure at large spatial extents. Progress can be made by: (1) developing statistical models with interaction matrices for multispecies co-occurrence datasets across large-scale environmental gradients, (2) testing the potential and limitations of methods for complexity reduction, and (3) sampling and monitoring comprehensive spatio-temporal data on biotic interactions in multispecies communities
Beck, J., Ballesteros-Mejia, L., Buchmann, C. M., Dengler, J., Fritz, S. A., Gruber, B., Hof, C., Jansen, F., Knapp, S., Kreft, H., Schneider, A. -K., Winter, M., Dormann, C. F.
What’s on the horizon for macroecology?
2012 Ecography, volume: 35, issue: 35, pages: 673 - 683

Abstract Over the last two decades, macroecology – the analysis of large-scale, multi-species ecological patterns and processes – has established itself as a major line of biological research. Analyses of statistical links between environmental variables and biotic responses have long and successfully been employed as a main approach, but new developments are due to be utilized. Scanning the horizon of macroecology, we identifi ed four challenges that will probably play a major role in the future. We support our claims by examples and bibliographic analyses. 1) Integrating the past into macroecological analyses, e.g. by using paleontological or phylogenetic information or by applying methods from historical biogeography, will sharpen our understanding of the underlying reasons for contemporary patterns. 2) Explicit consideration of the local processes that lead to the observed larger-scale patterns is necessary to understand the fi ne-grain variability found in nature, and will enable better prediction of future patterns (e.g. under environmental change conditions). 3) Macroecology is dependent on large-scale, high quality data from a broad spectrum of taxa and regions. More available data sources need to be tapped and new, small-grain large-extent data need to be collected. 4) Although macroecology already lead to mainstreaming cuttingedge statistical analysis techniques, we fi nd that more sophisticated methods are needed to account for the biases inherent to sampling at large scale. Bayesian methods may be particularly suitable to address these challenges. To continue the vigorous development of the macroecological research agenda, it is time to address these challenges and to avoid becoming too complacent with current achievements.

2011

Seppelt, R., Dormann, C. F., Eppink, F. V., Lautenbach, S., Schmidt, S.
A quantitative review of ecosystem service studies: approaches, shortcomings and the road ahead.
2011 J Appl Ecol, pages: 630 - 636

Abstract 1. Ecosystem services are defined as the benefits that humans obtain from ecosystems. Employing the ecosystem service concept is intended to support the development of policies and instruments that integrate social, economic and ecological perspectives. In recent years, this concept has become the paradigm of ecosystem management. 2. The prolific use of the term ‘ecosystem services’ in scientific studies has given rise to concerns about its arbitrary application. A quantitative review of recent literature shows the diversity of approaches and uncovers a lack of consistent methodology. 3. From this analysis, we have derived four facets that characterise the holistic ideal of ecosystem services research: (i) biophysical realism of ecosystem data and models; (ii) consideration of local trade-offs; (iii) recognition of off-site effects; and (iv) comprehensive but critical involvement of stakeholders within assessment studies. 4. These four facets should be taken as a methodological blueprint for further development and discussion. They should critically reveal and elucidate what may often appear to be ad-hoc approaches to ecosystem service assessments. 5. Synthesis and applications: Based on this quantitative review, we provide guidelines for further development and discussions supporting consistency in applications of the ecosystem service concept as well as the credibility of results, which in turn can make it easier to generalise from the numerous individual studies.
Maes, J., Braat, L., Jax, K., Hutchins, M., Furman, E., Termansen, M., Luque, S., Williams, M. L. P. C. C. R., Volk,M., Lautenbach, S., Kopperoinen, L., Schelhaas, M. -J., Weinert, J., Goossen, M., Dumont, E., Strauch, M.,, Görg, C., Dormann, C. F., Katwinkel, M., Zulian, G., Varjopuro, R., Ratamäki, O., Hauck, J., Forsius, M., Hengeveld, G., Soba, M. P., Bouraoui, F., Scholz, M., Schulz-Zunkel, C., Lepistö, A., Polishchuk, Y., Bidoglio, G.
A spatial assessment of ecosystem services in Europe: Methods, case studies and policy analysis - phase 1
2011 PEER Report, issue: 3, pages: 1 - 148

Abstract In order to make a comprehensive and compelling economic case for the conservation of ecosystems and biodiversity it is essential that we are able to understand, quantify and map the benefits received from ecosystems and biodiversity, and assign values to those benefits. The PRESS (PEER Research on Ecosystem Services) initiative is a collaboration between PEER (Partnership for European Environmental Research) research institutes addressing some of the knowledge gaps which stand in the way of performing a spatially-explicit, biophysical, monetary and policy assessment of ecosystem services in Europe. The starting point for this report is the need to upgrade the knowledge basis of land-use information and mapping to reflect the existing knowledge about ecosystem services and their social and economic values to better inform policy design and decision making processes. Ecosystem service maps have been developed for water purification and recreation as examples of regulating and cultural services, respectively. In the water purification case, the contribution of rivers, streams and lakes to purifying water through the removal of nutrient pollutants from runoff water was estimated in ton per km river network. The analysis showed that at a European scale, 1.5 milion ton of nitrogen is removed from surface waters, an amount equalling the combined input of point sources. The recreation study case has developed an approach for mapping recreation services offered by agricultural, semi-natural and natural areas considering also the accessibility of nature to citizens. Results show that the majority of the European population has access to areas where accessibility is high and where nature is of medium quality. For forest services, the assessment of methodological needs for mapping was completed. The analysis at regional and EU level revealed that there is high potential for integrating ecosystem services into policies and for supporting this with mapping exercises. The appearance of synergies and trade-offs and their relevance for decision-making is strongly dependent on the scale of the discussion and on the specific ways in which ecosystems are managed. This means that policies have a great potential to harmonise trade-offs or conflicts between ecosystem services e.g. by supporting specific management practices. There is a need for the development of hierarchical sets of ecosystem service indicators, following the European SEBI (streamlining European biodiversity indicators) example, but geographically explicit and linked to the EU-2020 Biodiversity Strategy.
Johst, K., Drechsler, M., van Teeffelen, A.J.A., Hartig, F., Vos, C.C., Wissel, S., Wätzold, F., Opdam, P.
Biodiversity conservation in dynamic landscapes: trade-offs between number, connectivity and turnover of habitat patches.
2011 J Appl Ecol, issue: 48, pages: 1227 - 1235

Abstract Many species are adapted to landscapes with characteristic dynamics generated by ongoing habitat destruction and creation. Climate change and human land use, however, may change the dynamics of these landscapes. Studies have repeatedly shown that many species are not able to cope with such changes in landscape dynamics. Conservation policies must, therefore, explicitly address this threat. The way in which management should be modified when formerly static landscapes become dynamic or when landscape dynamics change is unclear. 2. Using an analytical formula for the rapid assessment of metapopulation lifetime in dynamic landscapes, we investigate if and how changes in one landscape attribute may be compensated by changes in another attribute to maintain species viability. We study such trade-offs considering both spatial (number, connectivity of patches) and temporal (patch destruction and creation rates) landscape attributes. 3. We show that increasing patch destruction can be compensated to a certain extent by improvements in other spatial and/or temporal landscape attributes. Focusing on trade-offs between management options reveals two key factors essential for management decisions: First, the trade-offs are generally nonlinear irrespective of considering spatial or temporal landscape attributes. Secondly, species can be grouped according to their response to particular management options. 4. Synthesis and applications. We demonstrate the usefulness of an analytical formula for calculating trade-offs between landscape attributes for a variety of landscapes and species. Two practical and robust management recommendations can be derived: (i) The nonlinearity of trade-offs implies that the effectiveness of conservation measures depends explicitly on the current level of landscape attributes. It must, therefore, be taken into account in conservation decision making. In particular, the existing level of patch turnover is decisive: if it is already high, improvements in other landscape attributes are ineffective in maintaining species viability. Thus, monitoring the current level of landscape attributes is indispensable for effective biodiversity conservation. (ii) Compensation of increased patch destruction by increased patch creation is only suitable for species with high dispersal propensity adapted to variable environments (aside from habitat patch turnover). This implies that conservation policies which rely on such compensation, like offsetting and conservation banking, are feasible only for this type of species.
Drechsler, M., Hartig, F.
Conserving biodiversity with tradable permits under changing conservation costs and habitat restoration time lags.
2011 Ecol Econ, issue: 70, pages: 533 - 541

Abstract Tradable permits are a common environmental policy instrument that has recently been applied also to the conservation of biodiversity. Biodiversity conservation differs in many respects to the classical applications of tradable permits like emissions control. One particularity is that, even if the permit system maintains a constant total amount of species habitat, habitat turnover (the destruction of a habitat and restoration elsewhere) affects the ecosystem. Another particularity is that the restoration of habitats often takes much time, leading to time lags between the initiation of restoration activities and the time when restored habitat is available for trading. We use an agent-based model of a tradable permit market to study the influence of heterogeneous and dynamic conservation costs and habitat restoration time lags on key variables of the market, such as the costs incurred to the market participants and the amount of habitat turnover. Our results show that there may be trade-offs between these key variables. We also find that restoration time lags can lead to fluctuations in permit prices that reduce the efficiency of the permit market. We conclude that temporal lags deserve a careful analysis when implementing tradable permit systems for the preservation of natural habitats and biodiversity.
Gladbach, D. J., Holzschuh, A., Scherber, C., Thies, C., Dormann, C. F., Tscharntke, T.
Crop-noncrop spillover: arable fields affect trophic interactions on wild plants in surrounding habitats
2011 Oecologia, issue: 166, pages: 433 - 441

Abstract Ecosystem processes in agricultural landscapes are often triggered by resource availability in crop and noncrop habitats. We investigated how oilseed rape (OSR; Brassica napus, Brassicaceae) affects noncrop plants in managed systems and semi-natural habitat, using trophic interactions among wild mustard (Sinapis arvensis, Brassicaceae), rape pollen beetles (Meligethes aeneus, Nitidulidae) and their parasitoids (Tersilochus heterocerus, Ichneumonidae). We exposed wild mustard as phytometer plants in two cropland habitat types (wheat field, field margin) and three noncrop habitat types (fallow, grassland, wood margin) across eight landscapes along a gradient from simple to complex (quantified as % arable land). Both landscape and local factors affected the abundance of rape pollen beetles and parasitoids. Rape pollen beetle infestation and parasitism rates on these plants were lower in noncrop habitats and higher in wheat fields and field margins, whereas beetles and parasitoids responded differently to landscape scale parameters. We found the hypothesized spillover from OSR crop onto wild plants in surrounding habitats only for parasitoids, but not for pollen beetles. Parasitism rates were not related to landscape simplification, but benefited from increasing proportions of OSR. In contrast, rape pollen beetles benefited from simple landscape structures, presumably due to multi-annual population build-ups resulting from long-term OSR planting (as part of the crop rotation). In conclusion, we showed that spillover from cropland affects parasitism rates on related wild plants outside cropland, which has not been shown so far, but can be expected to be a widespread effect shaping noncrop food webs.
Holzschuh, A., Dormann, C. F., Tscharntke, T., Steffan-Dewenter, I.
Expansion of mass-flowering crops leads to transient pollinator dilution and reduced wild plant pollination
2011 Proceedings of the royal society, volume: 278, pages: 3444 - 3451

Abstract Agricultural land use results in direct biodiversity decline through loss of natural habitat, but may also cause indirect cross-habitat effects on conservation areas. We conducted three landscape-scale field studies on 67 sites to test the hypothesis that mass flowering of oilseed rape (Brassica napus) results in a transient dilution of bees in crop fields, and in increased competition between crop plants and grassland plants for pollinators. Abundances of bumble-bees, which are the main pollinators of the grassland plant Primula veris, but also pollinate oilseed rape (OSR), decreased with increasing amount of OSR. This landscape-scale dilution affected bumble-bee abundances strongly in OSR fields and marginally in grasslands, where bumble-bee abundances were generally low at the time of Primula flowering. Seed set of Primula veris, which flowers during OSR bloom, was reduced by 20 per cent when the amount of OSR within 1 km radius increased from 0 to 15 per cent. Hence, the current expansion of bee-attractive biofuel crops results in transient dilution of crop pollinators, which means an increased competition for pollinators between crops and wild plants. In conclusion, mass-flowering crops potentially threaten fitness of concurrently flowering wild plants in conservation areas, despite the fact that, in the long run, mass-flowering crops can enhance abundances of generalist pollinators and their pollination service.
Gagic, V., Tscharntke, T., Dormann, C. F., Gruber, B., Wilstermann, A., Thies, C.
Food web structure and biocontrol in a four-trophic level system across a landscape complexity gradient.
2011 Proceedings of the Royal Society of London B, pages: 2946 - 2953

Abstract Decline in landscape complexity owing to agricultural intensification may affect biodiversity, food web complexity and associated ecological processes such as biological control, but such relationships are poorly understood. Here, we analysed food webs of cereal aphids, their primary parasitoids and hyperparasitoids in 18 agricultural landscapes differing in structural complexity (42–93% arable land). Despite little variation in the richness of each trophic group, we found considerable changes in trophic link properties across the landscape complexity gradient. Unexpectedly, aphid–parasitoid food webs exhibited a lower complexity (lower linkage density, interaction diversity and generality) in structurally complex landscapes, which was related to the dominance of one aphid species in complex landscapes. Nevertheless, primary parasitism, as well as hyperparasitism, was higher in complex landscapes, with primary parasitism reaching levels for potentially successful biological control. In conclusion, landscape complexity appeared to foster higher parasitism rates, but simpler food webs, thereby casting doubt on the general importance of food web complexity for ecosystem functioning.
Newbery, D.M., Lingenfelder, M., Poltz, K.F., Ong, R.C., Ridsdale, C.E.
Growth responses of understorey trees to drought perturbation in tropical rainforest in Borneo
2011 Forest Ecol Manag, volume: 262, pages: 2095 - 2107

Abstract At Danum Valley, Sabah, dipterocarp forest is affected by moderately-strong droughts which perturb the ecosystem. Analysing stem growth for c. 3700 understorey trees (12.5–<50 cm girth), measured over four periods (between 1986 and 2007), response to an ENSO-related event (1998) was followed. Relative growth rates (rgr) of the 48 most abundant species in the size class were considered individually, and as relative changes between periods. From them a measure reactivity was derived. Whilst a third of species differed from one another in rgr, within-species rates were highly variable: often species had very different (pluralistic) response patterns over time. The rgr decreased in the drought period, increased and overcompensated directly afterwards, and later returned to original levels. The forest displayed moderate resistance, and high resilience and stability within c. 4 years of the perturbation. Oscillatory responses were more pronounced among true understorey species than among small trees of overstorey ones, suggesting that the former might play a key role in stabilization. Environmental stochasticity in the form of coloured noise may therefore be causing a major part of the variation in rain forest dynamics and explain its complexity.
Dormann, C. F.
How to be a specialist? Quantifying specialisation in pollination networks.
2011 Network Biology, pages: 1 - 20

Abstract The analysis of ecological networks has gained a very prominent foothold in ecology over the last years. While many publications try to elucidate patterns about the networks, others are primarily concerned with the role of specific species in the network. The core challenge here is to tell specialists from generalists. While field data and observations can be used to directly assess specialisation levels, the indirect way through networks is burdened with problems. Here, I review eight measures to quantify specialisation in pollination networks (degree, node specialisation, betweenness, closeness, strength, pollination support, Shannon’s H and discrimination d’), the first four being based on binary, the others on weighted network data. All data and R-code are available as supplement and can be applied beyond pollination networks. The indices convey different concepts of specialisation and hence quantify different aspects. Still, there is some redundancy, with node specialisation and closeness quantifying the same properties, as do degree, betweenness and Shannon’s H. Using artificial and real network data, I illustrate the interpretation of the different indices and the importance of using a null model to correct for expectations given the different observed frequencies of interactions. For a well-described network the distributions of specialisation values do not differ from null model expectations for most indices. Finally, I investigate the effect of cattle grazing on the specialisation of an important pollinator in eight replicated pollination networks as an illustration of how to employ the specialisation indices, null models and permutation-based statistics in the analysis of specialisation in pollination networks. Keywords bipartite network; degree; discrimination; node specialisation index; pollinator; pollination service index; strength; two-mode network.
Pasho, E., Papanastasis, V.P., Pelz, D.R., Lako, T.
Inventory and evaluation of grasslands in Albania.
2011 Grass Forage Sci, volume: 66, pages: 123 - 137
Krewenka, K., Holzschuh, A., Tscharntke, T., Dormann, C. F.
Landscape elements as potential barriers and corridors for bees, wasps and parasitoids
2011 Biol Conserv, issue: 144, pages: 1816 - 1825

Abstract Habitat loss and fragmentation in agricultural landscapes lead to severe declines of abundance and richness of many insect species in the remaining isolated semi-natural habitats. We analysed possible barrier effects of large hedges and corridor effects of narrow grass strips that were hypothesized to affect foraging and dispersal of hymenopterans. We selected calcareous grasslands in the vicinity of Göttingen (Germany), which harbour high Hymenoptera diversity and are starting points for foraging and dispersal in the landscape. We installed pan traps to sample bees (i) on the grasslands; (ii) on grassland edges behind adjacent hedges (potential barriers) and without hedges; (iii) on grass strips in 100 m distance to the grassland, which were connected or unconnected to the grassland; and (iv) unconnected (isolated) grass strips in 300 m and 750 m distance to test for corridor and isolation effects on abundance and species richness of foraging wild bees. Additionally we provided trap nests for bees, wasps and their parasitoids on the grasslands and the strips. Species abundance and richness declined with increasing isolation from grasslands for foraging solitary bees, trap-nesting bees, wasps and parasitoids, but not for foraging bumblebees. Hedges did not confine movement of foraging bees. We found no mitigating effects of (100 m) corridor strips on any of the observed groups. We conclude that conservation of semi-natural habitats as sources of bee and wasp diversity is important and that grass strips act as sinks rather than corridors when high quality patches are nearby.
Tscharntke, T., Tylianakis, J. M., Rand, T. A., Didham, R. K., Fahrig, L., Batáry, P., Bengtsson, J., Clough, Y., Crist, T. O., Dormann, C. F., Ewers, R. M., Fründ, J., Holt, R. D., Holzschuh, A., Klein, A. M., Kleijn, D., Kremen, C., Landis, D. A., Laurance, W., Lindenmayer, D., Scherber, C., Sodhi, N., Steffan-Dewenter, I., Thies, C., Van der Putten, W. H., Westphal
Landscape moderation of biodiversity patterns and processes
2011 Biol Rev, issue: 87, pages: 661 - 685

Abstract Understanding how landscape characteristics affect biodiversity patterns and ecological processes at local and landscape scales is critical for mitigating effects of global environmental change. In this review, we use knowledge gained from human-modified landscapes to suggest eight hypotheses, which we hope will encourage more systematic research on the role of landscape composition and configuration in determining the structure of ecological communities, ecosystem functioning and services. We organize the eight hypotheses under four overarching themes. Section A: ‘landscape moderation of biodiversity patterns’ includes (1) the landscape species pool hypothesis—the size of the landscape-wide species pool moderates local (alpha) biodiversity, and (2) the dominance of beta diversity hypothesis—landscapemoderated dissimilarity of local communities determines landscape-wide biodiversity and overrides negative local effects of habitat fragmentation on biodiversity. Section B: ‘landscape moderation of population dynamics’ includes (3) the cross-habitat spillover hypothesis—landscape-moderated spillover of energy, resources and organisms across habitats, including between managed and natural ecosystems, influences landscape-wide community structure and associated processes and (4) the landscape-moderated concentration and dilution hypothesis—spatial and temporal changes in landscape composition can cause transient concentration or dilution of populationswith functional consequences. Section C: ‘landscape moderation of functional trait selection’ includes (5) the landscape-moderated functional trait selection hypothesis—landscape moderation of species trait selection shapes the functional role and trajectory of community assembly, and (6) the landscape-moderated insurance hypothesis—landscape complexity provides spatial and temporal insurance, i.e. high resilience and stability of ecological processes in changing environments. Section D: ‘landscape constraints on conservation management’ includes (7) the intermediate landscape-complexity hypothesis—landscapemoderated effectiveness of local conservation management is highest in structurally simple, rather than in cleared (i.e. extremely simplified) or in complex landscapes, and (8) the landscape-moderated biodiversity versus ecosystem service management hypothesis—landscape-moderated biodiversity conservation to optimize functional diversity and related ecosystem services will not protect endangered species. Shifting our research focus from local to landscape-moderated effects on biodiversity will be critical to developing solutions for future biodiversity and ecosystem service management.
Fründ, J., Dormann, C. F., Tscharntke, T.
Linné’s floral clock is slow without pollinators - flower closure and plant-pollinator interaction webs.
2011 Ecology Letters, issue: 9, pages: 896 - 904

Abstract Temporal patterns of flower opening and closure within a day are known as Linné’s floral clock. Time of flower closure has been explained mainly by light in the traditional botanical literature. We show with a set of experiments that Asteraceae flower heads can close within three hours after pollination, whereas un-pollinated flower heads stay open until the late afternoon. This suggests that closing time strongly depends on pollinators. Using plant-pollinator interaction webs we further demonstrate that the daily pattern of flower opening and the rapid response to pollination can impose strong temporal dynamics on interspecific interactions within a single day. We observed pollinator species turnover and changes in facilitation vs. competition among plants. Our results show for the first time that pollination induces rapid flower closure on the community level. This causes imprecision in Linné’s floral clock with far-reaching consequences for plant-pollinator interactions.
Everaars, J., Strohbach, M., Gruber, B., Dormann, C. F.
Microsite conditions dominate habitat selection of the red mason bee (Osmia bicornis, Hymenoptera: Megachilidae) in an urban environment: A case study from Leipzig, Germany
2011 Landscape and Urban Planning, pages: 15 - 21

Abstract The red mason bee (Osmia bicornis L.) is a common wild bee in urban environments which contributes to early-season pollination. We know only little about how any species of wild bee in cities responds to resource distribution or landscape structure and the urban habitat(s) that they prefer. We employed a citizen science approach to investigate drivers behind the spatial distribution of this solitary bee in the urban region of Leipzig (Germany). Volunteers hung trap nests at different locations and collected information on eight local, microsite conditions (such as sun exposure, attachment position, local flower availability). We derived 14 landscape factors from a digital GIS biotope data map (e.g. distance to flower sites and urban matrix properties such as size and edge length of patches). Both occurrence and abundance of O. bicornis were then analyzed using a combination of machine learning and multiple (logistic) regression. The results indicate that the red mason bee is ubiquitous in urban area but clearly profits from nearby floral resources. Although we expected a balanced influence of landscape factors and microsite conditions, we found that hang location of the trap nest was most important, followed by sun exposure. Cities with many fine-scaled floral resources (such as private gardens but not parks) and an open housing structure with higher sun exposure between buildings provide a good environment for cavity-nesting bees such as O. bicornis. In places without suitable nesting opportunities, artificial nest can support the bees.
Dormann, C. F.
Modelling species' distributions. In: Jopp F, Reuter H, Breckling B (eds) Modelling Complex Ecological Dynamics.
2011 Springer, Berlin,, pages: 179 - 196

Abstract Species distribution models have become a commonplace exercise over the last 10 years, however, analyses vary due to different traditions, aims of applications and statistical backgrounds. In this chapter, I lay out what I consider to be the most crucial steps in a species distribution analysis: data pre-processing and visualisation, dimensional reduction (including collinearity), model formulation, model simplification, model type, assessment of model performance (incl. spatial autocorrelation) and model interpretation. For each step, the most relevant considerations are discussed, mainly illustrated with Generalised Linear Models and Boosted Regression Trees as the two most contrasting methods. In the second section, I draw attention to the three most challenging problems in species distribution modelling: identifying (and incorporating into the model) the factors that limit a species range; separating the fundamental, realised and potential niche; and niche evolution.
Gruber, B., Eckel, K., Everaars, J., Dormann, C. F.
On managing the red mason bee (Osmia bicornis) in apple orchards.
2011 Apidologie, pages: 564 - 576

Abstract Abstract – Aworldwide decline of pollinator abundance is recorded and the worldwide pollination of insectpollinated crops has traditionally depended on a single species, the honeybee. The risks of relying on a single species are obvious. Other species have been developed for particular crops. Here we present an extension of the framework of Bosch and Kemp (2002) that deals on how to develop a bee species into a crop pollinator. We used nesting aids in different settings to address five important issues that are necessary for an effective management of a bee species in a commercial setting. Our study system was the red mason bee (Osmia bicornis) in apple orchards in eastern Germany, but our approach should be transferable to other settings. The first issue was to demonstrate that it is possible to increase population size of O. bicornis by providing nesting aids. Second, we present how someone can study landscape features that promote the occurrence and abundance of O. bicornis. Further, we studied the dispersal of the species inside the orchard, and could demonstrate that bees prefer to disperse along lines of trees. Finally, we studied the effect of nesting substrate and type of farming on the recruitment of bees. We found a close relationship between the length of nesting tubes and achieved sex ratio and a negative effect of conventional farming on the number of nests built. We conclude with recommendations on how our findings can be used to optimize the management of O. bicornis in apple orchards.
Wätzold, F., Drechsler, M., Hartig, F., Wissel, S.
Permit Trading in Different Applications
2011 Routledge, page: 338

Abstract Permit trading is an environmental policy instrument that has received increasing levels of attention over recent years. Coming from the field of air quality management, with the European CO2 emissions trading system being the most prominent example, it enters new fields of application, such as land use policy and biodiversity protection, water quality and water quantity trading. This book gives an overview of these recent developments and discusses the possibilities and limits of permit trading in environmental policies. The advantages of permit trading are not only seen with respect to economic efficiency, which leads to achieving the environmental target at minimum cost, but also with respect to the instrument’s environmental effectiveness. By setting a cap for the overall emissions, a given environmental target can be met. This makes permit trading an interesting case for many environmental fields where safeguarding the environmental target plays a dominant role. Against this background, permit trading is discussed in environmental policy fields, where it has not been considered before, for example, land use management, biodiversity protection and water trading. Permit Trading in Different Applications analyses the properties of permit trading: its possibilities and limitations, its design options and its restrictions on a more general level. It demonstrates how lessons learnt in established policy fields like air quality management can be transferred to new and emerging fields of application. This collection will provide students and practitioners in environmental sciences and policy with valuable research into instrument choice and design with respect to permit trading.
Compton, T.J., Kraan, C., Rijkenberg, M.J.A., Troost, T.A., Rogers, D.I., Leyrer, J., Pearson, G., Piersmak, T.
Sampling bivalves on tidal flats: possibility of missing rare species, versus smoothing of environmental variation
2011 Marine Ecology Progress Series, issue: 440, pages: 285 - 288

Abstract Beukema & Dekker (2011; Mar Ecol Prog Ser 440:281−283) argue that the main conclusion of Compton et al. (2008; Mar Ecol Prog Ser 373:25–35), namely that diversity of bivalve and other benthic organisms on tidal flats is not associated with sediment heterogeneity, is invalid because γ-diversity was not examined. Our conclusion was, however, based on γ-diversity. Beukema & Dekker (2011) also argue that our finding that bivalve point diversity was highest in ‘complex’ fine-grained sediments is incorrect, because small sampling areas underestimate rare species. Using larger sampling areas would have increased the probability of including rare species, but would also have smoothed away biological and environmental heterogeneity. We used many estimates of point diversity to show that bivalve diversity at a sampling point was higher in finer versus sandier sediments across 9 mudflats and we did not make assumptions about the homogeneity of habitat types. The suggestion that samples should be aggregated on the basis of similar environmental attributes across an area as large as the Wadden Sea would also lead to an under- or overestimation of species diversity because—although sampling locations may share the same sediment characteristics—species composition within a sample will differ due to historical, physical and biological effects.
Tscharntke, T., Dormann, C. F., Batáry, P.
Set-aside management: How do succession, sowing patterns and landscape context affect biodiversity?
2011 Agr Ecosyst Environ, issue: 143, pages: 37 - 43

Abstract European Union (EU) member states set aside between 5 and 15% of arable land during the last two decades, but abolition of the set-aside scheme in 2008 caused a sudden loss in habitat availability and biodiversity in agricultural landscapes. Management of set-aside has many facets and in this perspective paper we focus on the biodiversity effects of successional age, sowing strategies and landscape context. Young, 1–2-year-old set-asides have been initially considered to be too ephemeral to have any conservation value. However, when a rich seed and bud bank is available, a species-rich natural (secondary) succession can be observed. Arable (annual) weed communities in the first two years of succession can even include endangered plant species with associated rare insect consumers. Furthermore, many bird species benefit from early-successional habitats, whereas small mammal communities are richer in older habitats. If the local plant species pool is poor, sowings of diverse mixtures from regional seed collections can be recommended. Set-aside managers using species-rich sowings often experience that dominant weeds suppress the less competitive annual species. This trend to species-poor communities can be avoided by intraspecific aggregation of competitively weak species. Broadening the spatial scale from the plot to the landscape, efficiency of set-aside is highest in simple landscapes, where set-aside exhibits greatest effect in enhancement of biodiversity and associated services such as pollination and biological control. In complex landscapes, however, additional set-aside does not add much to the high level of biodiversity and ecological processes already present. Twenty percent of semi-natural, non-crop habitat appears to be a rough threshold for enhancing biodiversity and sustaining services such as pollination and biological control, but improved set-aside management should have the potential to reduce the percentage of semi-natural non-crop habitat needed. EU policy should tailor set-aside schemes for the maintenance of biodiversity and also consider that management efficiency is higher in simple than complex landscapes.
Unterseher, M., Jumpponen, A., Öpik, M., Tedersoo, L., Moora, M., Dormann, C. F., Schnittler, M.
Species abundance distributions and richness estimations in fungal metagenomics – lessons learned from community ecology
2011 Mol Ecol, volume: 20, pages: 275 - 285

Abstract Results of diversity and community ecology studies strongly depend on sampling depth. Completely surveyed communities follow log-normal distribution, whereas power law functions best describe incompletely censused communities. It is arguable whether the statistics behind those theories can be applied to voluminous next generation sequencing data in microbiology by treating individual DNA sequences as counts of molecular taxonomic units (MOTUs). This study addresses the suitability of species abundance models in three groups of plant-associated fungal communities – phyllosphere, ectomycorrhizal and arbuscular mycorrhizal fungi. We tested the impact of differential treatment of molecular singletons on observed and estimated species richness and species abundance distribution models. The arbuscular mycorrhizal community of 48 MOTUs was exhaustively sampled and followed log-normal distribution. The ectomy- corrhizal (153 MOTUs) and phyllosphere (327 MOTUs) communities significantly differed from log-normal distribution. The fungal phyllosphere community in particular was clearly undersampled. This undersampling bias resulted in strong sensitivity to the exclusion of molecular singletons and other rare MOTUs that may represent technical artefacts. The analysis of abundant (core) and rare (satellite) MOTUs clearly identified two species abundance distributions in the phyllosphere data – a log-normal model for the core group and a log-series model for the satellite group. The prominent log-series distribution of satellite phyllosphere fungi highlighted the ecological significance of an infrequent fungal component in the phyllosphere community.
Hartig, F., Calabrese, J. M., Reineking, B., Wiegand, T., Huth, A.
Statistical inference for stochastic simulation models - theory and application
2011 Ecol Lett, issue: 14, pages: 816 - 827

Abstract Statistical models are the traditional choice to test scientific theories when observations, processes or boundary conditions are subject to stochasticity. Many important systems in ecology and biology, however, are difficult to capture with statistical models. Stochastic simulation models offer an alternative, but they were hitherto associated with a major disadvantage: their likelihood functions can usually not be calculated explicitly, and thus it is difficult to couple them to well-established statistical theory such as maximum likelihood and Bayesian statistics. A number of new methods, among them Approximate Bayesian Computing and Pattern-Oriented Modelling, bypass this limitation. These methods share three main principles: aggregation of simulated and observed data via summary statistics, likelihood approximation based on the summary statistics, and efficient sampling. We discuss principles as well as advantages and caveats of these methods, and demonstrate their potential for integrating stochastic simulation models into a unified framework for statistical modelling.
Bütof, A., von Riedmatten, L. R., Dormann, C. F., Scherer-Lorenzen, M., Welk, E., Bruelheide, H.
The responses of grassland plants to experimentally simulated climate change depend on land use and region.
2011 Global Change Biol, volume: 18, pages: 127 - 137

Abstract Macroclimatic niche properties derived from species distribution ranges are fundamental for projections of climate change impacts on biodiversity. However, it has been recognized that changes in regional or local distribution patterns also depend on interactions with land use. The reliability and transferability of large scale geographic predictions to small scale plant performance need to be tested experimentally. Thus, we asked how grassland plant species pairs with different macroclimatic niche properties respond to increased spring temperature and decrease summer precipitation in three different land-use types. An experiment was carried out in the framework of the German Biodiversity Exploratories simulating climate change in 45 experimental plots in three geographical regions (Schorfheide-Chorin, Hainich-Dün, Schwäbische Alb) and three grassland management types (meadow, pasture, mown pasture). We planted six plant species as phytometers, each two of them representing congeneric species with contrasting macroclimatic niches and recorded plant survival and growth over 1 year. To quantify the species macroclimatic niches with respect to drought tolerance, the species’ distribution ranges were mapped and combined with global climate data. The simulated climate change had a general negative effect on plant survival and plant growth, irrespective of the macroclimatic niche characteristics of the species. Against expectation, species with ranges extending into drier regions did not generally perform better under drier conditions. Growth performance and survival was best in mown pastures, representing a quite intensive type of land use in all study regions. Species with higher macroclimatic drought tolerance were generally characterized by lower growth rates and higher survival rates in land-use types with regular mowing regimes, probably because of reduced competition in the growing season. In conclusion, plant species with similar climatic niche characteristics cannot be expected to respond consistently over different regions owing to complex interactions of climate change with land use practices.

Book reviews

Years: 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011

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2017

Dormann, C. F.
Vellend: The Theory of Ecological Communities. Princeton University Press, Princeton.
2017 Basic and Applied Ecology, volume: 19, page: 94

2016

Dormann, C. F.
Bayesian Models: A Primer for Ecologists, N.T. Hobbs & M.B. Hooten. Princeton University Press, Princeton, NJ.
2016 The Quarterly Review of Biology, volume: 91, pages: 354 - 355

2015

Hartig, F.
Book review: Dale & Fortin – The Revised Guide to Spatial Analysis
2015 Frontiers of Biogeography, volume: 7, issue: 2

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Dormann, C. F.
Book review: Ecological Statistics: Contemporary Theory and Application, G.A. Fox, S. Negrete-Yankelevich, V.J. Sosa. Oxford University Press, Oxford.
2015 Basic and Applied Ecology, volume: 16, page: 756-757

2014

Dormann, C. F.
Book review: Mutualistic Networks, J. Bascompte, P. Jordano. Princeton University Press, Princeton
2014 Basic Appl Ecol, volume: 15, pages: 370 - 371

2013

Dormann, C. F.
Book review: Daniel B. Botkin: The Moon in the Nautilus Shell – Discordant Harmonies Revisited. From Climate Change to Species Extinctions, How Life Persists in an Ever-Changing World.
2013 Basic Appl Ecol, issue: 14, pages: 366 - 368
Dormann, C. F.
Book review: Hastings & Gross: Encyclopedia of Theoretical Ecology.
2013 Basic Appl Ecol, issue: 14, pages: 91 - 92
Dormann, C. F.
Book review: Legendre & Legendre: Numerical Ecology, 3rd ed.
2013 Basic Appl Ecol, pages: 714 - 715
Dormann, C. F.
Book review: Richards: The Tragic Sense of Life: Ernst Haeckel and the Struggle Over Evolutionary Thought.
2013 Basic Appl Ecol, issue: 14, pages: 138 - 369

2012

Dormann, C. F.
Book review: Pla, Casanoves & Di Rienzo. Quantifying Functional Biodiversity
2012 Basic Appl Ecol, issue: 13, page: 390
Dormann, C. F.
Book review: Species Distribution Models for Species Distribution Modellers (Ecological Niches and Geographic Distributions, by Peterson, Soberón, Pearson, Anderson, Martínez‐Meyer, Nakamura, Araújo).
2012 Frontiers of Biogeography, issue: 4, pages: 59 - 60

2011

Dormann, C. F.
Forest Analytics with R.
2011 R Journal, page: 75
Dormann, C. F.
Magurran & McGill (Eds.) Biological Diversity - Frontiers in Measurement and Assessment
2011 Basic and Applied Ecology, issue: 12, pages: 554 - 555
Dormann, C. F.
Michel Loreau: From Populations to Ecosystems: Theoretical Foundations for a New Ecological Synthesis
2011 Basic and Applied Ecology, issue: 12, pages: 382 - 383

Books

Years: 2015

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2015

UNEP World Conservation Monitoring Centre
Manual of marine and coastal datasets of biodiversity importance
Weatherdon, L. V., Fletcher, R., Jones, M.C., Kaschner, K., Sullivan, E., Tittensor, D. P., Mcowen, C., Geffert, J. L., van Bochove, J. W., Thomas, H., Blyth, S., Ravillious, C., Tolley, M., Stanwell-Smith, D., Fletcher, S., Martin, C. S.

Abstract The availability and appropriate use of marine and coastal data form the foundation of effective decision-making. This manual, as the second edition of the manual published by Martin et al. in 2014, aims to provide an overview of global marine and coastal datasets of biodiversity importance. The intention is to address the fragmented information and guidance for users of marine data. Although not exhaustive, this review has resulted in the identification of 128 datasets, databases and data portals (Annex 2). The report also includes detailed standardised metadata for 69 of these reviewed datasets (Annex 3). The various challenges, gaps and limitations which can be presented by coastal and marine data are also discussed. If you have any comments, suggestions, or queries, please contact marine@unep-wcmc.org.

Book chapters

Years: 2016 | 2014

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2016

Miloslavich, P., Webb, T., Snelgrove, P. V. R., Berghe, E. V., Kaschner, K., Halpin, P. N., Reeves, R. R., Lascelles, B., Tarzia, M., Wallace, B. P., Dulvy, N., Simpfendorfer, C. A., Schillinger, G., Boustany A, Boustany, A., Collette, B., Graves, J. E., Obura, D., Edwards, M., Clark, M., Stocks, K., Morato, T., Tunnicliffe, V., Hopcroft, R., Archambault, P., Pepin, P., Tunnell, JW, J., Moretzsohn, F., Escobar-Briones, E., Ojaveer, H., Judith, G., Nakaoka, M., Fujikura, K., Yamano, H., Li, X., Venkataraman, K., Raghunathan, C., Griffiths, C. L., Bax, N.J., Butler, A. J., Brandt, A., Griffiths, H. J., Rice, J.
Extent of Assessment of Marine Biological Diversity
In: First Global Marine Assessment
2016, Oceans and Law Of the Sea, United Nations, page: Chapter 35,
Snelgrove, P. V. R., Berghe, E. V., Miloslavich, P., Archambault, P., Bailly, N., Brandt, A., Bucklin, A., Clark, M., Dahdouh-Guebas, F., Halpin, P., Hopcroft, R., Kaschner, K., Lascelles, B., Levin, L. A., Menden-Deuer, S., Menden-Deuer, S., Metaxas, A., Obura, D., Reeves, R. R., Rynearson, T., Stocks, K., Tarzia, M., Tittensor, D., Tunnicliffe, V., Wallace, B., Wanless, R. M., Webb, T., Bernal, P.
Global Patterns in Marine Biodiversity
In: First Global Marine Assessment
2016, Oceans and Law of the Sea, United Nations, page: Chapter 34,

2014

Everaars, J., Dormann, C. F.
Simulation of solitary (non-Apis) bees competing for pollen
In: In Silico Bees (ed J. Devillers)
2014, CRC Press, pages: 209 - 268,

Conference papers

Years: 2017 | 2014 | 2013 | 2012 | 2011

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2017

Klimetzek, D., Berberich, G. M., Paraschiv, M., Stancioiu, P. T., Grumpe, A.
Red wood ants (RWA, 'Formica rufa' - group) and tectonics in the East Carpathians (Romania).
2017 7th Central European Workshop of Myrmecology, Krakow, Poland

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2014

Klimetzek, D., Dormann, C. F.
Distribution and persistence of red wood ant nests: A geostatistical approach to 45 years of settlement.
2014 Xth European Congress of Entomology, York, UK
Berberich, G., Sattler, T., Klimetzek, D., Benk, S., Schöler, H. F., Atlas, E.
Organohalogens in nest gas of a Formica rufa supercolony.
2014 Xth European Congress of Entomology, York, UK
Berberich, G., Grumpe, A., Berberich, M., Klimetzek, D., Wöhler, C.
Statistical correlation of ant mounds ('Formica spp.') and gas-permeable fault structures in the West Eifel and the Freiburg-Bonndorfer-Grabenzone.
2014 Xth European Congress of Entomology, York, UK

2013

Klimetzek, D., Delb, H.
Differential effects of climate change on forest insect pests in Germany
2013 Tagung der Gesellschaft für allgemeine und angewandte Entomologie Göttingen
Haynes, K. J., Allstadt, A. J., Klimetzek, D.
Five pine defoliating insect species in Central Europe: evidence of climate driven changes in severity and frequency of outbreaks
2013 Tagung der Gesellschaft für allgemeine und angewandte Entomologie Göttingen
Berberich, G., Klimetzek, D., Wöhler, C., Grumpe, A.
Statistical correlation between red wood ant sites and tectonically active fault structures
2013 Tagung der Gesellschaft für allgemeine und angewandte Entomologie Göttingen
Klimetzek, D., Gewiß, H.-P., Parthey, N.
44 years of settlement behavior and population dynamics of hill‐building wood ants (1966 ‐ 2010) in Freiburg area (SW‐Germany)
2013 5th Central European Workshop of Myrmecology, Innsbruck, Austria , supplement: 5
Berberich, G., Berberich, M., Klimetzek, D., Wöhler, C., Grumpe, A.
Statistical correlation between red wood ant mounds ('Formica spp.') and active fault structures in the West Eifel and the Freiburg-Bonndorfer-Grabenzone
2013 5th Central European Workshop of Myrmecology, Innsbruck, Austria

2012

Berberich, G., Klimetzek, D., Berberich, M., Schreiber, U.
A red wood ant supercolony as a bioindicator for neotectonic fault structures at the peninsula Bodanrueck (southwest Germany)
2012 Entomological Society of America, 60th Annual Meeting, Knoxville/TN , volume: 65819
Klimetzek, D., Berberich, G., Berberich, M., Schreiber, U.
Wood ants prefer neotectonic faults: 50 years of a Formica rufa – supercolony in southwest Germany
2012 Entomological Society of America, 60th Annual Meeting, Knoxville/TN , volume: 65821
Berberich, G., Klimetzek, D., Berberich, M., Schreiber, U.
GeoBioScience: Rote Waldameisen und geogene Gase als Indikatoren für aktive Tektonik auf dem Bodanrück (Bodensee)
2012 127. Versammlung der GDNÄ, Göttingen.
Berberich, G., Klimetzek, D., Schreiber, U., Berberich, M.
Geogenic gases and red wood ant clusters as indicators for neotectonic activity at the peninsula Bodanrück (south west Germany).
2012 EGU General Assembly 2012, Vienna, OE Geophysical Research Abstracts., volume: 14, page: 3488
Berberich, G., Klimetzek, D., Wöhler, C., Grumpe, A.
Statistical correlation between red wood ant sites and neotectonic strike-slip faults
2012 EGU General Assembly 2012, Vienna, OE Geophysical Research Abstracts, volume: 14, page: 3518

2011

Halbig, P., Delb, H., Henke, L., Wagenhoff, E., Klimetzek, D.
Monitoring and risk assessment of the Pine Processionary Moth, 'Thaumetopoeqa pityocampa' (DEN. & SCHIFF. 1775) ('Lep., Notodontidae'), for the Upper Rhine Valley.
2011 Tagung der Gesellschaft für allgemeine und angewandte Entomologie Berlin

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