@phdthesis{Schaefer2019,
  author    = {Sch{\"a}fer, Merlin},
  title     = {Understanding and predicting global change impacts on migratory birds},
  doi       = {10.25932/publishup-43925},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-439256},
  school      = {Universit{\"a}t Potsdam},
  pages     = {XIV, 153},
  year      = {2019},
  abstract  = {This is a publication-based dissertation comprising three original research stud-ies (one published, one submitted and one ready for submission; status March 2019). The dissertation introduces a generic computer model as a tool to investigate the behaviour and population dynamics of animals in cyclic environments. The model is further employed for analysing how migratory birds respond to various scenarios of altered food supply under global change. Here, ecological and evolutionary time-scales are considered, as well as the biological constraints and trade-offs the individual faces, which ultimately shape response dynamics at the population level. Further, the effect of fine-scale temporal patterns in re-source supply are studied, which is challenging to achieve experimentally. My findings predict population declines, altered behavioural timing and negative carry-over effects arising in migratory birds under global change. They thus stress the need for intensified research on how ecological mechanisms are affected by global change and for effective conservation measures for migratory birds. The open-source modelling software created for this dissertation can now be used for other taxa and related research questions. Overall, this thesis improves our mechanistic understanding of the impacts of global change on migratory birds as one prerequisite to comprehend ongoing global biodiversity loss. The research results are discussed in a broader ecological and scientific context in a concluding synthesis chapter.},
  language  = {en}
}
@article{SchaeferMenzJeltschetal.2017,
  author    = {Sch{\"a}fer, Merlin and Menz, Stephan and Jeltsch, Florian and Zurell, Damaris},
  title     = {sOAR: a tool for modelling optimal animal life-history strategies in cyclic environments},
  series = {Ecography : pattern and diversity in ecology ; research papers forum},
  volume    = {41},
  journal   = {Ecography : pattern and diversity in ecology ; research papers forum},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0906-7590},
  doi       = {10.1111/ecog.03328},
  pages     = {551 -- 557},
  year      = {2017},
  abstract  = {Periodic environments determine the life cycle of many animals across the globe and the timing of important life history events, such as reproduction and migration. These adaptive behavioural strategies are complex and can only be fully understood (and predicted) within the framework of natural selection in which species adopt evolutionary stable strategies. We present sOAR, a powerful and user-friendly implementation of the well-established framework of optimal annual routine modelling. It allows determining optimal animal life history strategies under cyclic environmental conditions using stochastic dynamic programming. It further includes the simulation of population dynamics under the optimal strategy. sOAR provides an important tool for theoretical studies on the behavioural and evolutionary ecology of animals. It is especially suited for studying bird migration. In particular, we integrated options to differentiate between costs of active and passive flight into the optimal annual routine modelling framework, as well as options to consider periodic wind conditions affecting flight energetics. We provide an illustrative example of sOAR where food supply in the wintering habitat of migratory birds significantly alters the optimal timing of migration. sOAR helps improving our understanding of how complex behaviours evolve and how behavioural decisions are constrained by internal and external factors experienced by the animal. Such knowledge is crucial for anticipating potential species' response to global environmental change.},
  language  = {en}
}
@article{Schaefer2019,
  author    = {Sch{\"a}fer, Merlin},
  title     = {Mut macht einsam},
  series = {Vielfalt in der Uckermark : Forschungsprojekte 2015 - 2018},
  journal   = {Vielfalt in der Uckermark : Forschungsprojekte 2015 - 2018},
  publisher = {oerding print GmbH},
  address   = {Braunschweig},
  pages     = {52 -- 53},
  year      = {2019},
  language  = {de}
}
@article{ZurellvonWehrdenRoticsetal.2018,
  author    = {Zurell, Damaris and von Wehrden, Henrik and Rotics, Shay and Kaatz, Michael and Gross, Helge and Schlag, Lena and Sch{\"a}fer, Merlin and Sapir, Nir and Turjeman, Sondra and Wikelski, Martin and Nathan, Ran and Jeltsch, Florian},
  title     = {Home range size and resource use of breeding and non-breeding white storks along a land use gradient},
  series = {Frontiers in Ecology and Evolution},
  volume    = {6},
  journal   = {Frontiers in Ecology and Evolution},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {2296-701X},
  doi       = {10.3389/fevo.2018.00079},
  pages     = {11},
  year      = {2018},
  abstract  = {Biotelemetry is increasingly used to study animal movement at high spatial and temporal resolution and guide conservation and resource management. Yet, limited sample sizes and variation in space and habitat use across regions and life stages may compromise robustness of behavioral analyses and subsequent conservation plans. Here, we assessed variation in (i) home range sizes, (ii) home range selection, and (iii) fine-scale resource selection of white storks across breeding status and regions and test model transferability. Three study areas were chosen within the Central German breeding grounds ranging from agricultural to fluvial and marshland. We monitored GPS-locations of 62 adult white storks equipped with solar-charged GPS/3D-acceleration (ACC) transmitters in 2013-2014. Home range sizes were estimated using minimum convex polygons. Generalized linear mixed models were used to assess home range selection and fine-scale resource selection by relating the home ranges and foraging sites to Corine habitat variables and normalized difference vegetation index in a presence/pseudo-absence design. We found strong variation in home range sizes across breeding stages with significantly larger home ranges in non-breeding compared to breeding white storks, but no variation between regions. Home range selection models had high explanatory power and well predicted overall density of Central German white stork breeding pairs. Also, they showed good transferability across regions and breeding status although variable importance varied considerably. Fine-scale resource selection models showed low explanatory power. Resource preferences differed both across breeding status and across regions, and model transferability was poor. Our results indicate that habitat selection of wild animals may vary considerably within and between populations, and is highly scale dependent. Thereby, home range scale analyses show higher robustness whereas fine-scale resource selection is not easily predictable and not transferable across life stages and regions. Such variation may compromise management decisions when based on data of limited sample size or limited regional coverage. We thus recommend home range scale analyses and sampling designs that cover diverse regional landscapes and ensure robust estimates of habitat suitability to conserve wild animal populations.},
  language  = {en}
}