Heavy metal concentrations in diet and livers of Black-crowned Night Heron Nycticorax nycticorax and Grey Heron Ardea cinerea chicks from Pyeongtaek, Korea

Abstract

This study presents concentrations of iron, manganese, zinc, copper, lead and cadmium in diet and livers of Black-crowned Night Heron Nycticorax nycticorax and Grey Heron Ardea cinerea chicks from Pyeongtaek, Gyeonggi-do, Korea. Heavy metal concentrations of heron chicks were not related to concentrations in the diet. Copper concentrations were significantly greater in the diet of Black-crowned Night Herons (geometric mean = 13.6 wet microg/g) than Grey Herons (7.45 wet microg/g), other metal concentrations did not differ between the diet of two species. Manganese (respectively 3.20 wet microg/g, 1.41 wet microg/g) and cadmium (respectively 13.4 wet microg/kg, 1.41 wet microg/kg) concentrations were higher in livers of Black-crowned Night Heron chicks than Grey Heron chicks, but zinc, iron, copper and lead concentrations in livers did not differ in between two herons. The essential elements were at background levels, however copper concentrations were relatively higher than previously reported from Korea. Lead and cadmium concentrations were within background levels for herons.