The University of Texas at Austin Marine Science Institute, Port Aransas, TX, United States of America.
University of Hawaii at Manoa, Hawaii Institute of Marine Biology, Kaneohe, HI, United States of America.
Sci Total Environ. 2021 Jan 10;751:141804. doi: 10.1016/j.scitotenv.2020.141804. Epub 2020 Aug 19.
Crude oil is a well-known toxicant that reduces cardiorespiratory performance in acutely exposed fishes. While toxic effects can manifest in death in severe cases, the ecological consequences of sub-lethal exposure remain uncertain. This study investigated the impact of crude oil exposure on long-term social competition, growth, and metabolic performance in a coastal species, the red drum (Sciaenops ocellatus). Fish were acutely exposed to either control or one of two environmentally relevant oil concentrations and reared together in groups of 15 (5 from each exposure concentration) for eight weeks under resource-rich or resource-limited scenarios. Relative to controls, a 41.3% and 45.9% reduction in the specific growth rate was-observed following exposure to 25.3 and 53.4 μg l ΣPAH respectively under resource-limited conditions. These fish were subsequently sampled for metabolic performance and common indicators of social subordination including reduced glucocorticoid receptors in the gill and caudal fin damage. The reduction in specific growth rate coincided with a 15.1% and 17.3% reduction in standard metabolic rate; however, maximum metabolic rate and aerobic scope were unaffected. Additionally, measures of social subordination showed no differences between oil-exposed and control fish. These results reinforce the hypothesis that acute oil exposure can have prolonged sub-lethal effects that compromise the ability of exposed individuals to perform effectively in their environment, including gathering and/or metabolizing food. Furthermore, this work highlights the premise that oil spills can be more detrimental in already at-risk ecosystems.
原油是一种众所周知的有毒物质，会降低急性暴露鱼类的心肺功能表现。虽然在严重情况下，毒性作用可能表现为死亡，但亚致死暴露的生态后果仍不确定。本研究调查了原油暴露对沿海物种红鼓鱼（Sciaenops ocellatus）的长期社会竞争、生长和代谢性能的影响。将鱼急性暴露于对照或两种环境相关油浓度之一中，并在资源丰富或资源有限的情况下，每组 15 条（每组 5 条）共同饲养 8 周。与对照组相比，在资源有限的条件下，暴露于 25.3 和 53.4μg l ΣPAH 分别导致特定生长率降低了 41.3%和 45.9%。随后对这些鱼进行了代谢性能和常见社会从属指标的采样，包括鳃和尾鳍损伤的皮质酮受体减少。特定生长率的降低与标准代谢率降低 15.1%和 17.3%相一致；然而，最大代谢率和有氧范围不受影响。此外，社会从属度的衡量指标在暴露于油的鱼和对照组之间没有差异。这些结果强化了这样一种假设，即急性石油暴露会产生长期的亚致死影响，从而损害暴露个体在其环境中有效执行任务的能力，包括觅食和/或代谢食物的能力。此外，这项工作强调了这样一个前提，即石油泄漏在已经处于危险中的生态系统中可能更具危害性。
