Data from: Multiple stressors in a top predator seabird: potential ecological consequences of environmental contaminants, population health and breeding conditions

• Main Authors: Bustnes, Jan Ove, Bourgeon, Sophie, Leat, Eliza H. K., Magnusdottir, Ellen, Strøm, Hallvard, Hanssen, Sveinn A., Petersen, Aevar, Olafsdottir, Kristin, Borgå, Katrine, Gabrielsen, Geir W., Furness, Robert W.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2016
• Subjects: multiple stressors; pollution; Great skua; Stercorarius skua; present; Bear Island; Bjørnøya; Iceland
• Online Access: https://doi.org/10.5061/dryad.7ts26

Environmental contaminants may have impacts on reproduction and survival in wildlife populations suffering from multiple stressors. This study examined whether adverse effects of persistent organic pollutants (POPs) increased with poor population health and breeding conditions in three colonies (60–74°N) of great skua (Stercorarius skua) in the north-eastern Atlantic (Shetland, Iceland and Bjørnøya [Bear Island]). POPs (organochlorines [OCs] and polybrominated diphenyl ethers [BDEs]) were measured in plasma of incubating birds (n = 222), concentrations differing nearly tenfold among colonies: Bjørnøya (2009) > Bjørnøya (2010) > Iceland (2009) > Shetland (2009). Reproductive success (hatching success and chick survival) showed that breeding conditions were favourable in Shetland and at Bjørnøya (2010), but were very poor in Iceland and at Bjørnøya (2009). Biomarkers indicated that health was poor in the Shetland population compared to the other populations. Females whose chicks hatched late had high POP concentrations in all colonies except at Bjørnøya (2010), and females losing their eggs at Bjørnøya (2009) tended to have higher concentrations than those hatching. Moreover, there was a negative relationship between female POP concentrations and chick body condition at hatching in Iceland and at Bjørnøya (2010). Supplementary feeding experiments were conducted, and in Iceland where feeding conditions were poor, significant negative relationships were found between female POP concentrations and daily growth-rate in first-hatched chicks of control nests, but not in food supplemented nests. This suggests that negative impacts of POPs were mitigated by improved feeding conditions. For second-chicks, there was a strong negative relationship between the female POP concentrations and growth-rate, but no effects of supplementary feeding. Lowered adult return-rate between breeding seasons with increasing POP loads were found both at Bjørnøya (2009) and in Shetland, especially related to BDEs. This indicates ...