Department of Fish, Wildlife and Conservation Biology, 1474 Campus Delivery, Colorado State University, Fort Collins, CO 80523-1474, USA.
Colorado Division of Parks and Wildlife, Aquatic Research Section, 317 West Prospect Road, Fort Collins, CO 80526, USA.
Sci Total Environ. 2015 Feb 15;506-507:330-7. doi: 10.1016/j.scitotenv.2014.10.101. Epub 2014 Nov 24.
Mercury (Hg) is a persistent global contaminant that biomagnifies, often reaching maximum levels in apex predators. Mercury contamination in piscivorous fish is a serious health risk for anglers and other fish consumers. We used data collected from a reservoir in Colorado to develop bioenergetics-based simulations of Hg bioaccumulation to estimate Hg concentrations in walleye (Sander vitreus), a popular sport fish. We evaluated how changes in the prey available to walleye might affect walleye Hg concentrations. Our simulations showed that such changes could result in almost a 10-fold range in walleye Hg concentration. Walleye consuming invertebrates had low growth, low growth efficiency, and high Hg concentrations. Conversely, when walleye diet contained only fish prey their growth and growth efficiency were higher and Hg concentrations were about 85% lower. These predictions were consistent with independent measurements in the study system observed under two different prey regimes in 2008 and 2013. Because prey assemblages in freshwaters can exhibit high natural and anthropogenic variability, understanding variation in predator Hg and providing accurate fish consumption advice to anglers and their families will require frequent monitoring of both predator and prey species. Further, manipulation of prey assemblages is a routine fishery management strategy that could be applied to reduce Hg contamination in piscivorous fishes.
汞 (Hg) 是一种持久性的全球性污染物，具有生物放大作用，通常在顶级捕食者中达到最高水平。食鱼鱼类中的汞污染对垂钓者和其他鱼类消费者的健康构成严重威胁。我们使用从科罗拉多州一个水库收集的数据，开发了基于生物能量学的汞生物累积模拟，以估计一种受欢迎的运动鱼类——大眼梭鲈 (Sander vitreus) 中的汞浓度。我们评估了大眼梭鲈可获取的食物变化如何影响其体内的汞浓度。我们的模拟结果表明，这种变化可能导致大眼梭鲈体内的汞浓度在近 10 倍的范围内波动。摄食无脊椎动物的大眼梭鲈生长缓慢、生长效率低且体内汞浓度高。相反，当大眼梭鲈的食物仅为鱼类时，其生长和生长效率更高，体内的汞浓度约低 85%。这些预测与 2008 年和 2013 年在该研究系统中观察到的两种不同猎物条件下的独立测量结果一致。由于淡水生物群落中的猎物组合可能具有高度的自然和人为变异性，因此要了解捕食者体内的汞变化并为垂钓者及其家人提供准确的鱼类消费建议，需要频繁监测捕食者和猎物物种。此外，猎物组合的操纵是一种常规的渔业管理策略，可用于减少食鱼鱼类中的汞污染。
