Spurenelementanreicherung in arktischen und borealen Meeresvögeln
Age-related, geographical and interspecific differences in metal accumulations were investigated in three seabird species. Samples were collected in Runde and Hornoya/ Norway, Brittany, German Bight. In beached or starving Common Guillemots negative correlations were found only between Zn, Cu and Se levels and the nutritional state. Thus Guillemots can be used as bioindicators for local contamination with Hg and Cd. In Kittiwake nestlings from the Island of Helgoland, egg contamination and the elimination of Hg via the loss of downy feathers was more important for Hg accumulation with age than contaminated food items. The influence of moult and tissue growth on Hg accumulation was most evident in these birds. Cadmium accumulation depend on the ingestion of contaminated food during chick development. The elevated Hg and Cd contents in Kittiwakes from arctic regions compared to Guillemots could be attributed to the variable feeding habits of this species. It was possible to separate Kittiwake populations of Hornoya and Runde and Guillemots of Brittany and the German Bight according to their metal contaminations.