We investigated concentrations of blood total mercury (THg) in three extant populations of endangered Whooping Crane (Grus americana). Blood THg was greater in cranes reintroduced during 2001–2008 that range in the eastern US (median = 0.31 ug/g ww) than both wild cranes in central North America (median = 0.11 ug/g ww) and from captivity (median = 0.01 ug/g ww). The median THg blood concentrations in the two free-ranging populations of Whooping Cranes were low compared to reproductive toxic thresholds suggested for other large bird species (> 4.3 ug/g ww), but a singular elevated concentration was observed in one crane (1.04 ug/g ww; 6% of samples from the reintroduced population). These results likely reflect variable dietary Hg exposure among these populations, but should prompt additional biomonitoring to discern risk of greater Hg exposure nearer to the time of breeding and potential effects on productivity.

我们调查了现存的三个濒临灭绝的鸣鹤 ( Grus americana ) 种群的血液总汞 (THg) 浓度）。2001 年至 2008 年期间，美国东部范围内重新引入的鹤的血液 THg 高于北美中部的野生鹤（中位数 = 0.11 ug/g ww）（中位数 = 0.31 ug/g ww）和圈养（中位数 = 0.01） ug/g ww)。与其他大型鸟类建议的生殖毒性阈值（> 4.3 ug/g ww）相比，百日鹤的两个自由放养种群的血液中 THg 中位数浓度较低，但在一只鹤（1.04 ug /g ww；6% 的样本来自重新引入的群体）。这些结果可能反映了这些人群中不同的膳食汞暴露情况，但应促使进行额外的生物监测，以识别更接近繁殖时间的汞暴露风险以及对生产力的潜在影响。