Department of Earth & Environmental Science. Acadia University, Wolfville, Nova Scotia B4P 2R6, Canada.
Department of Biology, Acadia University, Wolfville, Nova Scotia B4P 2R6, Canada.
Ecotoxicol Environ Saf. 2021 Dec 15;226:112845. doi: 10.1016/j.ecoenv.2021.112845. Epub 2021 Oct 6.
Avian biovector transport is an important mechanism for the movement of contaminants and nutrients to remote locations, usually bird colonies, through excretion, molting and decomposition of carcasses. Methylmercury (MeHg) is a bioaccumulative neurotoxin and endocrine disruptor which is present in many remote ecosystems. We collected guano samples biweekly from a herring gull (Larus smithsoniansus) colony over two summers and analyzed MeHg, total mercury (THg), water-extractable phosphate (PO) and sulfate (SO). Concentrations of THg in guano declined through the summer months while %MeHg significantly increased (ranging from 12% to 100% of THg), suggesting a switch in diet as gull nutritional needs or food availability changed through the summer. The percentage of PO in dry guano increased throughout the summer (ranging from 2.8% to 4.4% of dry weight) and SO varied throughout the season (ranging from 0.1% to 0.8% of dry weight). These data indicate that gulls are transporting considerable amounts of MeHg, PO, and likely other contaminants to Big Meadow Bog, Nova Scotia.
鸟类生物载体传输是污染物和养分通过排泄、蜕皮和尸体分解，向偏远地区（通常是鸟类聚居地）迁移的重要机制。甲基汞（MeHg）是一种生物累积性神经毒素和内分泌干扰物，存在于许多偏远生态系统中。我们在两个夏季内每两周从一只银鸥（Larus smithsoniansus）聚居地采集鸟粪样本，并分析了其中的 MeHg、总汞（THg）、水可提取磷酸盐（PO）和硫酸盐（SO）。鸟粪中 THg 的浓度在夏季逐月下降，而%MeHg 显著增加（THg 的 12%至 100%），这表明随着夏季营养需求或食物供应的变化，海鸥的饮食发生了变化。整个夏季，干鸟粪中的 PO 百分比一直在增加（占干重的 2.8%至 4.4%），SO 的含量在整个季节内变化（占干重的 0.1%至 0.8%）。这些数据表明，银鸥正在将大量的 MeHg、PO 以及可能其他污染物输送到新斯科舍省的大草甸沼泽。
