Mercury and methylmercury in liver tissue from ringed herring gulls collected in three Danish localities

In connection with a large scale reduction of herring gulls population, 119 ringed herring gulls were collected from Hirsholmene (Oresund), and Christiansø (Baltic Sea) in the spring of 1975 and 1976. The gulls had been ringed at the respective localities where they were later killed. An average of 0.65 mg Hg/kg liver (wet weight) was found with considerable differences between the three localities.