Interrelated impacts of climate and land‐use change on a widespread waterbird

• Published in: Journal of Animal Ecology
• Main Authors: Saunders, Sarah P., Piper, Walter, Farr, Matthew T., Bateman, Brooke L., Michel, Nicole L., Westerkam, Henrik, Wilsey, Chad B.
• Other Authors: Division of Environmental Biology, Division of Integrative Organismal Systems, National Science Foundation, National Geographic Society
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2021
• Subjects: North Atlantic; North Atlantic oscillation
• Online Access: http://dx.doi.org/10.1111/1365-2656.13444; https://onlinelibrary.wiley.com/doi/pdf/10.1111/1365-2656.13444; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/1365-2656.13444; https://besjournals.onlinelibrary.wiley.com/doi/am-pdf/10.1111/1365-2656.13444; https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/1365-2656.13444

Abstract Together climate and land‐use change play a crucial role in determining species distribution and abundance, but measuring the simultaneous impacts of these processes on current and future population trajectories is challenging due to time lags, interactive effects and data limitations. Most approaches that relate multiple global change drivers to population changes have been based on occurrence or count data alone. We leveraged three long‐term (1995–2019) datasets to develop a coupled integrated population model‐Bayesian population viability analysis (IPM‐BPVA) to project future survival and reproductive success for common loons Gavia immer in northern Wisconsin, USA, by explicitly linking vital rates to changes in climate and land use. The winter North Atlantic Oscillation (NAO), a broad‐scale climate index, immediately preceding the breeding season and annual changes in developed land cover within breeding areas both had strongly negative influences on adult survival. Local summer rainfall was negatively related to fecundity, though this relationship was mediated by a lagged interaction with the winter NAO, suggesting a compensatory population‐level response to climate variability. We compared population viability under 12 future scenarios of annual land‐use change, precipitation and NAO conditions. Under all scenarios, the loon population was expected to decline, yet the steepest declines were projected under positive NAO trends, as anticipated with ongoing climate change. Thus, loons breeding in the northern United States are likely to remain affected by climatic processes occurring thousands of miles away in the North Atlantic during the non‐breeding period of the annual cycle. Our results reveal that climate and land‐use changes are differentially contributing to loon population declines along the southern edge of their breeding range and will continue to do so despite natural compensatory responses. We also demonstrate that concurrent analysis of multiple data types facilitates deeper ...