Influence of trophic position and foraging range on mercury levels within a seabird community

Marine Ecology Progress Series

S. Bearhop¹  R. A. McDonald¹  R. A. Phillips¹  R. F. Shore¹  R. A. R. McGill¹  O. R. J. Anderson¹ 

关键词: Mercury;    Procellariiformes;    δ15N;    δ13C;    Trophic position;    Diet;    Seabird;   

DOI  :  10.3354/meps07784

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: Seabirds are often advocated as biomonitors for marine contaminants such as mercury (Hg). However, contaminant levels can vary widely depending on among-individual and among-species variation in foraging preferences and physiology, and on tissue types used for analyses. Using stable isotope analysis (SIA), we investigated the effects of trophic position, season, and tissue type on Hg burdens in a group of 10 closely related seabirds (Procellariiformes) from a single colony in the South Atlantic. Analysis of blood (reflecting breeding season diet) showed that among-species Hg concentrations varied as a function of trophic position (δ¹⁵N) and were also influenced to a lesser degree by foraging range (δ¹³C). This pattern did not hold for feathers, which reflect the non-breeding period. Mercury levels in feathers formed during the non-breeding season appear to be more strongly governed by species effects (such as moult schedule), demonstrating the need to carefully consider tissue type when formulating predictions regarding Hg burdens and dynamics. Assessment at a community rather than the species level, and across a number of tissue types, provided a more complete picture of the complex interactions between Hg and foraging ecology in seabirds.

【 授权许可】

Unknown