MEPS 375:277-288 (2009)  -  doi:10.3354/meps07784

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

O. R. J. Anderson1,*, R. A. Phillips2, R. A. McDonald3, R. F. Shore4, R. A. R. McGill5, S. Bearhop1,6

1School of Biological Sciences, MBC, Queen’s University Belfast, Lisburn Road, Belfast BT9 7BL, UK
2British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK
3Central Science Laboratory, Sand Hutton, York YO41 1LZ, UK
4Centre for Ecology and Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP, UK
5Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 0QF, UK
6Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK

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.

KEY WORDS: Mercury · Procellariiformes · δ15N · δ13C · Trophic position · Diet · Seabird

Full text in pdf format 
Cite this article as: Anderson ORJ, Phillips RA, McDonald RA, Shore RF, McGill RAR, Bearhop S (2009) Influence of trophic position and foraging range on mercury levels within a seabird community. Mar Ecol Prog Ser 375:277-288

Export citation: Endnote - Reference Manager
Mail this link - Contents Mailing Lists - RSS
- -