Spatiotemporal variation of ringed seal blubber cortisol levels in the Canadian Arctic

Abstract Climate change in the Arctic has widespread and complex effects on the health of animals and their populations. We used radioimmunoassay to measure blubber cortisol in ringed seals (Pusa hispida) sampled in Ulukhaktok, Inuvialuit Settlement Region, Northwest Territories, Canada (spring, 200...

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Bibliographic Details
Published in:Journal of Mammalogy
Main Authors: Ogloff, Wesley R, Anderson, Randi A, Yurkowski, David J, Debets, Cassandra D, Anderson, W Gary, Ferguson, Steven H
Other Authors: Flaherty, Elizabeth, Fisheries and Oceans Canada, ArcticNet, Natural Sciences and Engineering Research Council of Canada Discovery, Faculty of Graduate Studies and Biological Sciences Department at the University of Manitoba
Format: Article in Journal/Newspaper
Language:English
Published: Oxford University Press (OUP) 2022
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Online Access:http://dx.doi.org/10.1093/jmammal/gyac047
https://academic.oup.com/jmammal/article-pdf/103/5/1208/46331853/gyac047.pdf
Description
Summary:Abstract Climate change in the Arctic has widespread and complex effects on the health of animals and their populations. We used radioimmunoassay to measure blubber cortisol in ringed seals (Pusa hispida) sampled in Ulukhaktok, Inuvialuit Settlement Region, Northwest Territories, Canada (spring, 2002, 2004–2005, 2007–2012) and Arviat, Nunavut, Canada (autumn, 2003–2012) to examine chronic stress relative to biology (age, sex, length), body condition (blubber depth), and diet (δ13C, δ15N, and isotopic niche size). Ulukhaktok ringed seals had higher cortisol concentrations overall (0.46 ± 0.04 ng/g) than Arviat ringed seals (0.36 ± 0.03 ng/g), and these higher concentrations were associated with higher muscle δ15N and lower blubber thickness. In contrast, blubber cortisol concentrations for Arviat ringed seals decreased with blubber depth and increased with age, though testing of age effects individually suggests that age-related patterns are weak. Annual mean cortisol concentration increased from 2003 to 2012 in Arviat ringed seals, but low sample sizes precluded analysis of annual patterns for Ulukhaktok ringed seals. The trend of increased cortisol over time in Arviat ringed seals suggests that they might be experiencing greater chronic stress over time, which could have implications for numerous population health metrics including reproduction and pup recruitment.