Spatial and temporal variability in ringed seal (Pusa hispida) stable isotopes in the Beaufort Sea

• Published in: Ecology and evolution Vol. 10; no. 10; pp. 4178 - 4192
• Main Authors: Boucher, Nicole P., Derocher, Andrew E., Richardson, Evan S.
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.05.2020; John Wiley and Sons Inc; Wiley
• Subjects: Animal behavior; Annual variations; Beaufort Sea; Climate change; Diet; Ecological monitoring; Ecosystem dynamics; Ecosystem structure; Ecosystems; Environmental changes; Environmental conditions; Geographical locations; Ice; Isotopes; Metabolism; niche width; Niches; Original Research; Polar environments; Prey; Productivity; Pusa hispida; ringed seal; Sea ice; Sea surface temperature; Stable isotopes; Trends; Trophic levels; Water circulation; Water temperature; Winter; Beaufort Sea; Hudson Bay; Arctic region; niche width; stable isotopes; Beaufort Sea; Pusa hispida; ringed seal; climate change
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.6186

Arctic ecosystem dynamics are shifting in response to warming temperatures and sea ice loss. Such ecosystems may be monitored by examining the diet of upper trophic level species, which varies with prey availability. To assess interannual variation in the Beaufort Sea ecosystem, we examined spatial and temporal trends in ringed seal (Pusa hispida) δ13C and δ15N in claw growth layers grown from 1964 to 2011. Stable isotopes were correlated with climate indices, environmental conditions, seal population productivity, and geographic location. Sex and age did not influence stable isotopes. Enriched 13C was linked to cyclonic circulation regimes, seal productivity, and westward sampling locations. Higher δ15N was linked to lower sea surface temperatures, a higher percentage of pups in the subsistence harvest, and sample locations that were eastward and further from shore. From the 1960s to 2000s, ringed seal niche width expanded, suggesting a diversification of diet due to expansion of prey and/or seal space use. Overall, trends in ringed seal stable isotopes indicate changes within the Beaufort Sea ecosystem affected by water temperatures and circulation regimes. We suggest that continued monitoring of upper trophic level species will yield insights into changing ecosystem structure with climate change. To assess interannual variation in the Beaufort Sea ecosystem, we examined spatial and temporal trends in ringed seal (Pusa hispida) δ13C and δ15N in claw growth bands grown between 1964 and 2011. Stable isotopes correlated to climate indices, environmental conditions, seal population productivity, and geographic location. From the 1960s to 2000s, ringed seal niche width expanded, suggesting a diversification of diet due to expansion of prey and/or seal space use.