Loss of connectivity among island-dwelling Peary caribou following sea ice decline

Global warming threatens to reduce population connectivity for terrestrial wildlife through significant and rapid changes to sea ice. Using genetic fingerprinting, we contrasted extant connectivity in island-dwelling Peary caribou in northern Canada with continental-migratory caribou. We next examined if sea-ice contractions in the last decades modulated population connectivity and explored the possible impact of future climate change on long-term connectivity among island caribou. We found a strong correlation between genetic and geodesic distances for both continental and Peary caribou, even after accounting for the possible effect of sea surface. Sea ice has thus been an effective corridor for Peary caribou, promoting inter-island connectivity and population mixing. Using a time series of remote sensing sea-ice data, we show that landscape resistance in the Canadian Arctic Archipelago has increased by approximately 15% since 1979 and may further increase by 20–77% by 2086 under a hig...全球变暖正通过海冰的显著快速变化，威胁陆生野生动物的种群连通性。本研究利用遗传指纹分析（genetic fingerprinting），对比了加拿大北部岛屿栖息的皮尔里驯鹿（Peary caribou）与大陆迁徙驯鹿的现存种群连通性。随后我们分析了近数十年来海冰缩减是否调控了种群连通性，并探讨了未来气候变化对岛屿驯鹿种群长期连通性的潜在影响。研究发现，即便在控制海面潜在混杂效应的前提下，大陆驯鹿与皮尔里驯鹿的遗传距离与测地距离均存在显著相关性。由此可见，海冰一直是皮尔里驯鹿的有效扩散廊道，促进了岛间种群连通与基因交流。本研究借助遥感海冰数据的时间序列分析发现，加拿大北极群岛的景观阻力自1979年以来已提升约15%，到2086年时，在高（hig...）情景下可能进一步增加20%至77%。