Studies of seasonal changes in heavy metal contamination in three shorebird species at Teesmouth, North east England

Abstract

Concentrations of lead, cadmium, copper, and zinc were measured in kidney and liver tissues of three species of shorebirds that winter on the industrial River Tees estuary: Sanderling, Calidris alba; Ringed Plover, Charadrius hiatacula; and Grey Plover, Pluvialis sguatarola. Metal concentrations tended to be higher in kidneys than in livers of all three species. Seasonal variations in some metal oncentrations were observed in all three species, particularly in Sanderling for which the most samples were available. Zinc levels were found to correlate with other metal levels to some degree in all three species. Few differences in metal concentrations between sexes were found. Metal concentrations were also measured in the birds' main prey, respectively the polychaete Nerine cirratulus and various Crustaceans; the crustacean Corophium volutator; and the polychaete Nereis diversicolor. Metal concentrations in the birds and their prey were compared, and it was found that only very small amounts of metals ingested were retained.