Glaucous gull found dead during the breeding season in Bjørnøya. It died most likely due to high levels of PCB's in the blood. Photo: Odd Harald Selboskar, Norwegian Polar Institute

Rationale: Contaminant levels in biota show the levels of contaminants (radionuclides, heavy metals and POPs) at different trophic levels in marine food webs. When monitored over several years it would also be possible to determine spatial and temporal trends.