National Research Council Research Associateship Program, Under contract to Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, United States of America.
Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, United States of America.
PLoS One. 2019 Mar 22;14(3):e0214399. doi: 10.1371/journal.pone.0214399. eCollection 2019.
In the western United States, the long-term recovery of many Pacific salmon populations is inextricably linked to freshwater habitat quality. Industrial activities from the past century have left a legacy of pollutants that persist, particularly near working waterfronts. The adverse impacts of these contaminants on salmon health have been studied for decades, but the population-scale consequences of chemical exposure for salmonids are still poorly understood. We estimated acute and delayed mortality rates for seaward migrating juvenile Chinook salmon that feed and grow in a Superfund-designated area in the Lower Willamette River in Portland, Oregon. We combined previous, field-collected exposure data for juvenile Chinook salmon together with reduced growth and disease resistance data from earlier field and laboratory studies. Estimates of mortality were then incorporated into a life cycle model to explore chemical habitat-related fish loss. We found that 54% improved juvenile survival-potentially as a result of future remediation activities-could increase adult Chinook salmon population abundance by more than 20%. This study provides a framework for evaluating pollution remediation as a positive driver for species recovery.
在美国西部，许多太平洋三文鱼种群的长期恢复与淡水生境质量密不可分。上个世纪的工业活动留下了污染物的遗留物，特别是在工作码头附近。这些污染物对三文鱼健康的不利影响已经研究了几十年，但化学物质暴露对鲑鱼的种群规模的影响仍知之甚少。我们估计了在俄勒冈州波特兰市下威拉米特河中一个被超级基金指定的区域觅食和生长的洄游性幼三文鱼的急性和延迟死亡率。我们将以前收集到的幼三文鱼暴露数据与早期现场和实验室研究中获得的生长减缓和抗病力降低的数据结合起来。然后，将死亡率估计值纳入生命周期模型，以探讨与化学栖息地有关的鱼类损失。我们发现，54%的幼三文鱼存活率提高——可能是由于未来的补救活动——可能使成年三文鱼种群数量增加 20%以上。本研究为评估污染补救作为物种恢复的积极驱动因素提供了一个框架。
