Burger J, Nisbet I C, Gochfeld M
Department of Biological Sciences and Environmental and Occupational Health Sciences Institute (EOHSI), Rutgers University, Piscataway, NJ 08855.
J Toxicol Environ Health. 1992 Nov;37(3):363-74. doi: 10.1080/15287399209531677.
Birds are useful indicators of environmental contamination because they are relatively large, conspicuous, top predators in food chains. However, concentrations of contaminants in a bird's tissues reflect the bird's exposure over wide temporal and spatial scales. Birds are most useful as monitors of exposure when these scales are known. In this paper we report concentrations of lead, cadmium, mercury, and selenium in breast feathers of common terns (Sterna hirundo) and roseate terns (S. dougallii) trapped during incubation at breeding colonies in New York and Massachusetts. Terns arrived on the breeding grounds with breast feathers grown on their wintering grounds, and regrew certain feathers that were plucked for analysis. The regrown feathers were themselves plucked, and both sets of feathers were analyzed. For roseate terns at Cedar Beach and common terns at both sites there was a significant increase in mercury levels in the feathers grown on the breeding grounds compared to those grown on the wintering ground. The differences in mercury were far greater at Bird Island than at Cedar Beach. Selenium levels at Cedar Beach were higher for the regrown feathers than the initial feathers for roseate terns, but not for common terns. Lead and cadmium levels were not significantly different at either site for either species. These results suggest that terns are exposed to significantly higher levels of mercury in the northeastern United States than they are in the wintering grounds in South America.
鸟类是环境污染的有用指示生物，因为它们相对较大、较为显眼，是食物链中的顶级捕食者。然而，鸟类组织中的污染物浓度反映了其在广泛的时间和空间尺度上的暴露情况。当这些尺度已知时，鸟类作为暴露监测指标最为有用。在本文中，我们报告了在纽约和马萨诸塞州繁殖地孵化期间捕获的普通燕鸥（Sterna hirundo）和玫瑰燕鸥（S. dougallii）胸羽中铅、镉、汞和硒的浓度。燕鸥抵达繁殖地时，其胸羽是在越冬地生长的，并且会重新生长某些被拔下用于分析的羽毛。重新生长的羽毛被拔下后，对两组羽毛都进行了分析。对于雪松海滩的玫瑰燕鸥和两个地点的普通燕鸥，与在越冬地生长的羽毛相比，在繁殖地生长的羽毛中汞含量显著增加。鸟岛的汞含量差异比雪松海滩大得多。雪松海滩玫瑰燕鸥重新生长的羽毛中的硒含量高于初始羽毛，但普通燕鸥并非如此。两个地点的两种燕鸥的铅和镉含量均无显著差异。这些结果表明，美国东北部的燕鸥接触的汞含量比其在南美洲越冬地时显著更高。
