This study presents concentrations of iron, manganese, zinc, copper, lead, and cadmium in tissues of black-crowned night heron (Nycticorax nycticorax) (n = 8) and grey heron (Ardea cinerea) (n = 9) chicks from Pyeongtaek heronry, Gyeonggi-do, Korea, 2001. Iron (respectively, 45.8 +/- 24.0 microg/wet g, 155 +/- 123 microg/wet g), zinc (38.3 +/- 5.34 microg/wet g, 50.9 +/- 14.0 microg/wet g), and copper (9.93 +/- 2.26 microg/wet g, 30.2 +/- 12.9 microg/wet g) concentrations in feathers, manganese concentrations in livers (3.26 +/- 0.68 microg/ wet g, 1.50 +/- 0.58 microg/wet g), kidneys (1.43 +/- 0.27 microg/wet g, 0.84 +/- 0.34 microg/wet g), and bones (1.34 +/- 0.50 microg/wet g, 3.17 +/- 1.31 microg/wet g) were different between black-crowned night heron and grey heron chicks. Lead concentrations in bones (0.11 +/- 0.04 microg/wet g, 0.61 +/- 0.42 microg/wet g) and cadmium concentrations in liver (13.5 +/- 2.30 microg/wet kg, 10.3 +/- 1.59 microg/wet kg), kidney (6.61 +/- 2.54 microg/wet kg, 2.31 +/- 1.29 microg/wet kg), and muscle (5.25 +/- 5.91 microg/wet kg, 1.37 +/- 0.90 microg/wet kg) differed between chicks of the two heron species. The differences of heavy metal concentrations in tissues in herons and egrets were reported to other similar studies. Heavy metal concentrations for both heron species were at background levels. In both species, lead concentrations were higher in livers than in bones and cadmium concentrations were higher in livers than in kidneys. We suggest that it is not chronic exposure but acute exposure to lead and cadmium contamination around breeding site that leads to these observations. Therefore, lead and cadmium concentrations in tissues can be used as a bioindicator of acute local contamination.

This study presents concentrations of zinc, manganese, copper, lead, and cadmium in the feather of five shorebird species from Yeongjong Island, Korea in the East Asian-Australian migration flyways. The objectives of this study were to determine levels of heavy metal concentrations in the feathers of shorebirds, to evaluate the pattern of heavy metal concentrations in the feather and the liver, and to examine the correlation between heavy metal concentrations in the feathers and livers. We hypothesized that difference of heavy metal concentrations will show by the breeding ground of shorebirds. Lead concentrations in dunlins (geomean = 14.8 microg/g wet weight) and great knots (20.8 microg/g wet weight) feathers were significantly higher than Terek sandpipers (3.32 microg/g wet weight); other metals were not different among shorebirds. Zinc, lead, and cadmium concentrations in the feather were correlated with the liver concentrations, but manganese and copper concentrations were not. Zinc, manganese, copper, lead, and cadmium concentrations in the feather from this study were within the range of earlier studies for wild birds, but cadmium concentrations in dunlins were higher than other studies. Because lead concentrations in livers and feathers of the Terek sandpiper were lower than in other shorebirds, we suggest that Terek sandpipers were exposed to lower lead concentrations than Kentish plovers, dunlins, and great knots on their breeding ground.

This study presents concentrations of heavy metals (manganese, zinc, lead, and cadmium) in tissues in six orders of Korean wild birds (n=37), 2000-2002. Zinc, manganese, lead, and cadmium concentrations in all tissues were highest in ancient murrelets (Synthliboramphus antiquus). Essential elements in Korean wild birds were within the normal range for wild birds and are maintained there by a normal homeostatic mechanism. Lead concentrations in livers of almost all birds were within the background levels. Cadmium concentrations in livers and kidneys of ancient murrelets exceeded background levels for wild birds, but other birds were within the normal range. Acute and chronic contaminations of lead and cadmium levels differed among groups (or species). We suggest that differences in lead and cadmium concentrations among groups are because of differences in diet and habitat. In ancient murrelets, zinc and manganese concentrations correlated with their cadmium concentration in livers. Zinc, manganese, and cadmium concentrations in murrelet livers were also higher than in other species. Therefore, we suggest that high zinc and manganese concentrations in ancient murrelets were related to their high cadmium concentrations.

In order to understand the factors causing variation of lead and cadmium accumulation in tissues of feral pigeons in Seoul and Ansan, Korea, we investigated their age, food items (crop and gizzard contents) as well as environmental factors such as soil, atmosphere, and local traffic density. The results indicate that concentrations of Pb and Cd were highly increased in the order of eggs < chicks < adults. In food analysis, supplementary foods (rice, small stones, domestic scraps, cements, hairs, Styrofoam, etc.) could be considered as factors considering the Pb concentration differences. Concentrations of Cd in foodstuffs, the proportion of crop contents as their major foods could have an influence on the difference of Cd levels from a nutritional viewpoint. The Pb levels in gizzard contents and soil had an effect on the tissue accumulations, these were associated with the volume of vehicular traffic. However, we could not find any differences of Cd concentrations in gizzard contents and soil, although there were significantly different Cd accumulations in target organs of adult pigeons between the study areas. The Pb and Cd levels in tissues did not correspond to atmospheric metal levels.

This study measured concentrations of iron, manganese, zinc, copper, lead, and cadmium in environmental substrates (water and sediment) as well as in the diet and feathers of Black-crowned Night Heron Nycticorax nycticorax and Grey Heron Ardea cinerea chicks from Pyeongtaek heronry, Gyeonggi-do, Korea. Zinc and cadmium concentrations in sediment were relatively high, but lead was low. In the diet, only copper concentrations were higher in Black-crowned Night Herons than in Grey Herons. Cadmium concentrations in the diet of two heron species from a Pyeongtaek heron colony were also higher than reported in other studies. In feathers, iron, copper, and lead concentrations were significantly different between heron species. Iron and copper concentrations were higher in Black-crowned Night Heron chicks than in Grey Heron chicks, but lead concentrations were not. Therefore, with the exception of lead, heavy metal concentrations in feathers were not related to concentrations in the diet. Zinc, iron, and lead concentrations in heron feathers were within the ranges reported by other heron studies, but manganese, copper, and cadmium were much higher. Lead and cadmium concentrations in feathers of Black-crowned Night Heron and Grey Heron chicks were elevated to lead and cadmium concentrations in the diet. Therefore, we suggest that lead and cadmium concentrations in heron feathers reflect contamination of breeding sites and are useful bioindicators of local contamination.