Impacts of climate change on avian populations

Abstract

This review focuses on the impacts of climate change on population dynamics. I introduce the MUP (Measuring, Understanding and Predicting) approach, which provides a general framework where an enhanced understanding of climate-population processes, along with improved long-term data, are merged into coherent projections of future population responses to climate change. This approach can be applied to any species, but this review illustrates its bene t using birds as examples. Birds are one of the best-studied groups and a large number of studies have de- tected climate impacts on vital rates (i.e. life history traits, such as survival, matura- tion, or breeding, a ecting changes in population size and composition) and population abundance. These studies reveal multifaceted e ects of climate with direct, indirect, time- lagged and non-linear e ects. However, few studies integrate these e ects into a climate-dependent population model to understand the respective role of climate vari- ables and their components (mean state, variability, extreme) on population dynamics. To quantify how populations cope with climate change impacts, I introduce a new universal variable: the \population robustness to climate change." The comparison of such robustness, along with prospective and retrospective analysis may help to identify the major climate threats and characteristics of threatened avian species. Finally, studies projecting avian population responses to future climate change predicted by IPCC-class climate models are rare. Population projections hinge on selecting a multi-climate model ensemble at the appropriate temporal and spatial scales and integrating both radiative forcing and internal variability in climate with fully speci ed uncertainties in both demographic and climate processes.