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Comparison of Trace Element Concentrations Between Chick and Adult Black-Tailed Gulls (Larus crassirostris)
1Department of Environmental Science and Engineering, Kyung Hee University, 1 Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 446-701, Republic of Korea, herons@khu.ac.kr.
Abstract:
Trace elements were measured in the feathers of black-tailed gull chicks (n = 10) and adults (n = 10) collected at Chilsando Is., Jeollanam-do, Korea, in June 2011. Pb, Mn and Fe were significantly greater in adult (arithmetic mean 2.02, 3.81, 92.1 μg/g dw, respectively) than chick (0.74, 2.14, 68.7 μg/g dw) gulls. In contrast, Zn was greater in chicks (74.9 μg/g dw) than adults (46.5 μg/g dw). Cd, Pb and Cr in all chicks and adults were lower than an approximate threshold level for toxic effects. Cd, Pb and Cr were comparable or lower than reported in other gull studies worldwide. Essential elements including Al, Cu, Mn, Zn and Fe were within the background and normal physiological levels reported earlier in other gull species including black-tailed gulls.
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