Taylor Capwell E, Cristol Daniel A
Institute for Integrative Bird Behavior Studies, The College of William and Mary, Williamsburg, VA, 23187-8795, USA.
Bull Environ Contam Toxicol. 2015 Oct;95(4):459-64. doi: 10.1007/s00128-015-1643-0. Epub 2015 Aug 30.
Tree swallows nesting on mercury-contaminated sites along the South River in Virginia, USA were monitored for reproductive success. The bodies of nestlings found deceased in their nest boxes were collected, along with blood and feather samples from the adult parents and surviving siblings. We also measured hatching and fledging success of the clutches and the annual recapture rate of adults. We found that the body feathers of deceased nestlings contained significantly higher concentrations of mercury (12.89 ± 8.42 μg/g, n = 15) than those of nestlings that survived to fledge (7.41 ± 4.79 μg/g, n = 15). However, mothers of more successful clutches (>75 % hatching) did not differ in mercury concentrations from females with less successful clutches (<50 % hatching). Additionally, adult females breeding for the first time that returned to breed the following year did not differ in blood mercury from females of the same age that bred once but never returned. Our results suggest that mercury had its greatest effect on these songbirds during the nestling stage, whereas for embryos or first-time breeding females, other factors likely played larger roles in mortality.
对在美国弗吉尼亚州南河沿岸受汞污染地点筑巢的树燕的繁殖成功率进行了监测。收集了在巢箱中发现死亡的雏鸟尸体，以及成年亲鸟和存活同胞的血液和羽毛样本。我们还测量了窝卵数的孵化和出飞成功率以及成年鸟的年度重捕率。我们发现，死亡雏鸟的体羽汞浓度（12.89±8.42μg/g，n = 15）显著高于存活至出飞的雏鸟（7.41±4.79μg/g，n = 15）。然而，繁殖成功率较高（孵化率>75%）的窝卵数的雌鸟的汞浓度与繁殖成功率较低（孵化率<50%）的雌鸟并无差异。此外，次年返回繁殖的首次繁殖成年雌鸟的血液汞含量与繁殖一次但未返回的同龄雌鸟没有差异。我们的结果表明，汞在雏鸟阶段对这些鸣禽影响最大，而对于胚胎或首次繁殖的雌鸟，其他因素可能在死亡率中起更大作用。
