Scaling from individual interactions to community dynamics in avian assemblages
This research is supported by an Ambizione fellowship by the Swiss National Science Foundation (2016-2019; Grant no. PZ00P3_168136 to Damaris Zurell)
Summary
Biodiversity loss due to global environmental change is expected to increase rapidly throughout the 21st century posing a major challenge to nature conservation and society. In order to anticipate and mitigate negative impacts on ecosystem functions and services, models are needed that reliably depict the abiotic and biotic drivers that determine species and community response to environmental change. Correlative species distribution models (SDMs) have been widely used in this context, but remain criticised for only implicitly accounting for interspecific interactions and for not being able to properly disentangle the fundamental and realised niche of a species. Recently, new tools have been introduced that integrate SDMs with community ecological methods of co-occurrence analyses. So-called joint species distribution models (JSDMs) simultaneously estimate the distribution of multiple species and allow partitioning species co-occurrence patterns into species-specific environmental responses and residual correlations between species, which may result from interspecific interactions but also from unmeasured environmental factors. JSDMs provide an exciting development in macroecology and community ecology, but are still in its infancy with few available applications and without rigorous evaluation. Important questions remain regarding, for example, the scale dependence and spatiotemporal variation in interspecific interaction mechanisms and their effect on JSDM performance, the specific data needed for reliably identifying these mechanisms, and the applicability of JSDMs for climate impact assessments.
This project will focus on Swiss avian communities and aims at: (1) evaluating the ability of JSDMs to detect and reliably quantify different interspecific interaction mechanisms, and to predict avian communities under scenarios of climate change; (2) evaluating the scale dependence of interspecific interaction processes in avian assemblages and their relation to functional traits; (3) assessing the extent of spatial and temporal variation in interspecific interactions for selected bird assemblages; and (4) incorporating trait information into JSDMs to understand how behavioural syndromes mediate interspecific interactions in birds. To achieve these goals, the project will make use of the extensive bird monitoring programmes of Switzerland in close collaboration with the Swiss Ornithological Institute, supplemented by targeted simulation experiments that allow testing the models against specific underlying assumptions. The project is expected to provide both theoretical and conceptual advancements in model-based predictions of species range and community changes by explicitly studying the link between local scale biotic interactions and large-scale avian community patterns, and by combining extensive empirical and theoretical analyses to define practical requirements and guidelines for the implementation of community assemblage predictions. Moreover, it will help understanding the complexities of Swiss avian assemblages and help anticipating potential environmental change-induced changes to Swiss avian diversity.
Collaborators
- Catherine H Graham, Rafael O Wüest and Niklaus E Zimmermann, WSL, Switzerland
- Thomas Sattler and Marc Kéry, Swiss Ornithological Institute, Sempach, Switzerland