DISTRIBUTION AND AGE-RELATED-CHANGES OF TRACE-ELEMENTS IN KITTIWAKE RISSA-TRIDACTYLA NESTLINGS FROM AN ISOLATED COLONY IN THE GERMAN BIGHT,NORTH-SEA

Tissue distribution of five trace elements (Se, Hg, Cd. Zn, Cu) was in vestigated in soft tissues and feathers of Kittiwake nestlings from th e Island of Helgoland, North Sea. The tissue distribution of metals wa s similar in all age classes. Feathers and down contained highest merc ury and zinc concentrations, whereas elevated levels of selenium and c admium were found in the kidney. The concentrations of cadmium, copper and zinc in liver and kidney were low in hatchlings and increased wit h age of the nestlings, indicating the importance of the ingestion of contaminated food during chick growth. In the case of mercury, concent rations were high shortly after hatching and decreased when the chicks grew older. This indicates, that egg contamination was more important in chicks than contaminated food items. The total liver burden of all trace elements increased throughout chick development. Significant po sitive correlations between essential and non-essential elements were found in liver and/or kidney of all age classes. However, only the cor relations between zinc and copper levels maintained throughout chick g rowth. The number of Interactions between elements were increasing wit h progressing chick age. Correlations between cadmium and the essentia l elements copper and zinc appeared to depend on contaminant levels of cadmium, whereas mercury was correlated to essential elements in low and highly contaminated chicks. It was demonstrated that particularly older chicks (greater than or equal to 6 days old) were reliable bioin dicators of mercury and cadmium contaminations around Helgoland Island . Copyright (C) 1996 Elsevier Science B.V.