Dataset Information

Mercury exposure in an endangered seabird: long-term changes and relationships with trophic ecology and breeding success.

ABSTRACT: Mercury (Hg) is an environmental contaminant which, at high concentrations, can negatively influence avian physiology and demography. Albatrosses (Diomedeidae) have higher Hg burdens than all other avian families. Here, we measure total Hg (THg) concentrations of body feathers from adult grey-headed albatrosses (Thalassarche chrysostoma) at South Georgia. Specifically, we (i) analyse temporal trends at South Georgia (1989-2013) and make comparisons with other breeding populations; (ii) identify factors driving variation in THg concentrations and (iii) examine relationships with breeding success. Mean ± s.d. feather THg concentrations were 13.0 ± 8.0 µg g^-1 dw, which represents a threefold increase over the past 25 years at South Georgia and is the highest recorded in the Thalassarche genus. Foraging habitat, inferred from stable isotope ratios of carbon (?¹³C), significantly influenced THg concentrations-feathers moulted in Antarctic waters had far lower THg concentrations than those moulted in subantarctic or subtropical waters. THg concentrations also increased with trophic level (?¹⁵N), reflecting the biomagnification process. There was limited support for the influence of sex, age and previous breeding outcome on feather THg concentrations. However, in males, Hg exposure was correlated with breeding outcome-failed birds had significantly higher feather THg concentrations than successful birds. These results provide key insights into the drivers and consequences of Hg exposure in this globally important albatross population.

SUBMITTER: Mills WF

PROVIDER: S-EPMC7779510 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Mercury exposure in an endangered seabird: long-term changes and relationships with trophic ecology and breeding success.

Mills William F WF Bustamante Paco P McGill Rona A R RAR Anderson Orea R J ORJ Bearhop Stuart S Cherel Yves Y Votier Stephen C SC Phillips Richard A RA

Proceedings. Biological sciences 20201223 1941

Mercury (Hg) is an environmental contaminant which, at high concentrations, can negatively influence avian physiology and demography. Albatrosses (Diomedeidae) have higher Hg burdens than all other avian families. Here, we measure total Hg (THg) concentrations of body feathers from adult grey-headed albatrosses (<i>Thalassarche chrysostoma</i>) at South Georgia. Specifically, we (i) analyse temporal trends at South Georgia (1989-2013) and make comparisons with other breeding populations; (ii) id ...[more]

PMID: 33352077

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Dataset Information

Mercury exposure in an endangered seabird: long-term changes and relationships with trophic ecology and breeding success.

Publications

Mercury exposure in an endangered seabird: long-term changes and relationships with trophic ecology and breeding success.

Similar Datasets

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