Sea ice reduction drives genetic differentiation among Barents Sea polar bears

• Main Authors: Maduna, Simo Njabulo, Aars, Jon, Fløystad, Ida, Klutsch, Cornelya, Zeyl Fiskebeck, Eve, Wiig, Øystein, Ehrich, Dorothee, Andersen, Magnus, Bachmann, Lutz, Derocher, Andrew, Nyman, Tommi, Eiken, Hans Geir, Hagen, Snorre
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2021
• Subjects: Arctic; ice-dependent; Sea ice loss; Ursus maritimus; Barents Sea; Climate change; Sea ice; Svalbard
• Online Access: https://doi.org/10.5061/dryad.zpc866t8x

Loss of Arctic sea ice due to climate change is predicted to reduce both genetic diversity and gene flow in ice-dependent species, with potential negative consequences for their long-term viability. Here, we tested for the population-genetic impacts of reduced sea ice cover on the polar bear ( Ursus maritimus ) sampled across two decades (1995–2016) from the Svalbard Archipelago, Norway, an area that is affected by rapid sea ice loss in the Arctic Barents Sea. We analysed genetic variation at 22 microsatellite loci for 626 polar bears from four sampling areas within the archipelago. Our results revealed a 3-10% loss of genetic diversity across the study period, accompanied by a near 200% in genetic differentiation across regions. These effects may best be explained by a decrease in gene flow caused by habitat fragmentation due to loss of sea ice coverage, resulting in increased inbreeding of local polar bears within the focal sampling areas in the Svalbard Archipelago. This study illustrates the importance of genetic monitoring for developing adaptive management strategies for polar bears and other ice-dependent species. This repository contains the genotypic data and metadata file used to run the analyses for this paper and a readme file that contains an explanation of the columns in the dataset. Detailed information on how the datasets were generated can be found in the associated manuscript referenced above and its supplements. Funding provided by: World Wildlife Fund Crossref Funder Registry ID: http://dx.doi.org/10.13039/100001399 Award Number: