Improving species distribution models to predict climate change impacts: accounting for species traits, weather extremes, landscape dynamics and demography
Natalie J. Briscoe (1), Michael R. Kearney (2), Brendan A. Wintle (3)
1 School of BioSciences, University of Me lbourne, Vi ctoria, Australia, 3010, n b riscoe@unimelb .edu.au, @n jbriscoe
2 School of BioSciences, University of Me lbourne, Vi ctoria, Australia, 3010, mrke @u nimelb.ed u.au, @ecophys
3 School of BioSciences, University of Me lbourne, Vi ctoria, Australia, 3010, b .wintle@unimelb.edu.au
How climate change affects species will depe nd on physiology, landscape, population and dispersal dynamics, and existing stressors such as habitat loss. To generate robust predictions that can form the basis for conservation actions we therefore need an approach that integrates physiological constra ints on survival and reproduction with other demographic processes and threats. We outline a modelling framework that addresses this gap by integrating biophysical models with population dynamics models – and demonstrate its application using the koala ( Phascolarctos cinerus) as a case study. We first developed a biophysical model that calculates the survival, energy and water requirements of koalas based on daily weather, individual traits and local habitat features. By coupling this information with data on potential energy and water intake, we estimated how climate change will influence vital rates. Biophysical model output was then integrated with a stage -specific population dynamics model to predict how climate change will interact with other demographi c processes and threats to impact population persistence. Our innovative approach overcomes the widely -recognized short-comings of current static, correlative approaches to predicting the impacts of climate change and provides insight into the mechanisms t hrough which climate change will influence species persistence. This modelling framework can be used to identify key traits and quantify how trait variation influences survival and reproduction – a strong foundation for considering evolutionary responses. We illustrate how this approach can be used to identify climate refugia that provide suitable habitat and buffer populations from extreme events, as well as to evaluate how future management actions are likely to influence populations.