Nestling blood of the white-tailed sea eagle (Haliaeetus albicilla) as an indicator of territorial exposure to organohalogen compounds - An evaluation

This study was designed to evaluate the usefulness of nestling blood for mo nitoring' levers of organohalogen substances (OHS) in white-tailed sea eagl es (Haliaeetus albicilla). The concentrations of polychlorinated biphenyls (PCBs), 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (DDE), hexachlorobenzene (HCB),beta-hexachlorocyclohexane (beta-HCH), and one polybrominated phenox yanisol in nestling blood were determined. In addition at least 22 hydroxyl ated PCBs were indicated. Eagle nestlings did not demonstrate any changes i n concentrations of PCBs or DDE during 4-8 weeks of age. The variations in PCBs and DDE levels within a given territory between different years are si milar to the corresponding variation observed in white-tailed sea eagle egg s. Regional differences in the pattern of OHS were also found. Thus, the re sults indicate that nestling blood provides a good measure of territorial e xposure. However, to create a better basis for evaluation of contaminant le vels, more than one sampling year from each breeding territory is recommend ed. There is a significant negative correlation between the concentration o f 2,3',4,4',5-pentachlorobiphenyl and brood size. This observation indicate s that present levels of coplanar PCBs may stilt influence the reproduction of white-tailed sea eagles on the Baltic coast.