Demographic responses to climate change in a threatened Arctic species. Issue 15 (14th July 2021)

• Record Type: Journal Article
• Authors: Dunham, Kylee D.; Tucker, Anna M.; Koons, David N.; Abebe, Asheber; Dobson, F. Stephen; Grand, James B.
• Is Part Of: Ecology and evolution. Volume 11:Issue 15(2021)
• Page Start: 10627
• Page End: 10643
• Publication Date: 2021-07-14
• Subjects: Alaska -- Arctic Russia -- Bering sea -- full annual cycle -- integrated population models -- Somateria fischeri -- spectacled eiders; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.7873
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: The Arctic is undergoing rapid and accelerating change in response to global warming, altering biodiversity patterns, and ecosystem function across the region. For Arctic endemic species, our understanding of the consequences of such change remains limited. Spectacled eiders ( Somateria fischeri ), a large Arctic sea duck, use remote regions in the Bering Sea, Arctic Russia, and Alaska throughout the annual cycle making it difficult to conduct comprehensive surveys or demographic studies. Listed as Threatened under the U.S. Endangered Species Act, understanding the species response to climate change is critical for effective conservation policy and planning. Here, we developed an integrated population model to describe spectacled eider population dynamics using capture–mark–recapture, breeding population survey, nest survey, and environmental data collected between 1992 and 2014. Our intent was to estimate abundance, population growth, and demographic rates, and quantify how changes in the environment influenced population dynamics. Abundance of spectacled eiders breeding in western Alaska has increased since listing in 1993 and responded more strongly to annual variation in first‐year survival than adult survival or productivity. We found both adult survival and nest success were highest in years following intermediate sea ice conditions during the wintering period, and both demographic rates declined when sea ice conditions were above or below average. In recent years, sea ice extent has reached new record lows and has remained below average throughout the winter for multiple years in a row. Sea ice persistence is expected to further decline in the Bering Sea. Our results indicate spectacled eiders may be vulnerable to climate change and the increasingly variable sea ice conditions throughout their wintering range with potentially deleterious effects on population dynamics. Importantly, we identified that different demographic rates responded similarly to changes in sea ice conditions, emphasizing the need for integrated analyses to understand population dynamics. Abstract : Our understanding of the consequences of climate change for Arctic endemic species is limited. We developed an integrated population model to describe the population dynamics of spectacled eiders, a threatened Arctic sea duck. Our analysis revealed abundance has increased since listing under the Endangered Species Act in 1993, however, spectacled eiders are vulnerable to climate change and the increasingly variable sea ice conditions experienced throughout their core wintering range.