[en] In the Barents Sea, pelagic and coastal polar bears are facing various ecological challenges that may explain the difference in their pollutant levels. We measured polychlorinated biphenyls, organochlorine pesticides, polybrominated diphenyl ethers in fat, and perfluoroalkyl substances in plasma in pelagic and coastal adult female polar bears with similar body condition. We studied polar bear feeding habits with bulk stable isotope ratios of carbon and nitrogen. Nitrogen isotopes of amino acids were used to
nvestigate their trophic position. We studied energy expenditure by estimating field metabolic rate using telemetry data. Annual home range size was determined, and spatial gradients in pollutants were explored using latitude and longitude centroid positions of polar bears. Pollutant levels were measured in harp seals from the Greenland Sea and White Sea−Barents Sea as a proxy for a West−East gradient of pollutants in polar bear prey. We showed that pelagic bears had higher pollutant loads than coastal bears because (1) they feed on a higher proportion of marine and higher trophic level prey, (2) they have higher energy requirements and higher prey consumption, (3) they forage in the marginal ice zones, and (4) they feed on prey located closer to pollutant emission sources/transport pathways.
Disciplines :
Aquatic sciences & oceanology
Author, co-author :
Blévin, Pierre
Aars, Jon
Andersen, Magnus
Blanchet, Marie-Anne
Hanssen, Linda
Herzke, Dorte
Jeffreys, Rachel M.
Nordøy, Erling S.
Pinzone, Marianna ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Océanographie biologique
de la Vega, Camille
Routti, Heli
Language :
English
Title :
Pelagic vs Coastal - Key Drivers of Pollutant Levels in Barents Sea Polar Bears with Contrasted Space-Use Strategies
Alternative titles :
[en] Belgium
Publication date :
2020
Journal title :
Environmental Science and Technology
ISSN :
0013-936X
eISSN :
1520-5851
Publisher :
American Chemical Society, Washington, United States - District of Columbia
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