Incidental capture of protected fishes usually calls for immediate release, however, post-release survival has not been investigated for many protected species. The American eel Anguilla rostrata is an example of an imperiled species that is incidentally captured by recreational anglers, but for which the impacts of catch and release are unknown. In this study, we examined the short-term (7 d) mortality and injury of American eels (n = 207) following simulated catch-and-release scenarios (involving manually embedded hooks) in a controlled experiment. Specifically, we compared the effects of cutting the line versus removing the hook, as well as shallow versus deep hooking, in holding tanks. No mortalities occurred in any of the groups during a 7 d monitoring period, and most eels exhibited little to mild injury. A high degree of hook shedding occurred in groups where the hook was shallowly embedded. Hooking depth was significantly related to hook-shedding rate, with 93.7% of hooks shed in the shallow-hook−line-cut group compared to 71.8% of hooks shed in the deep-hook−line-cut group. Our results suggest that recreationally captured American eels may be relatively resilient to catch and release, but validation of these results in a field setting is recommended.

中文翻译：

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捕捉和释放钓鱼对美国鳗鱼构成威胁吗？一个钩子死亡率实验

受保护鱼类的偶然捕获通常需要立即释放，但是，尚未对许多受保护物种的释放后存活情况进行调查。美洲鳗 Anguilla rostrata 是一个濒危物种的例子，它被休闲垂钓者偶然捕获，但捕获和释放的影响未知。在这项研究中，我们在受控实验中检查了模拟捕获和释放场景（涉及手动嵌入的钩子）后美国鳗鱼（n = 207）的短期（7 天）死亡率和伤害。具体而言，我们比较了在储罐中切割线与移除钩子以及浅钩与深钩的效果。在 7 d 的监测期内，各组均未发生死亡，大多数鳗鱼表现出轻微至轻度损伤。在钩子嵌入较浅的组中发生高度的钩子脱落。钩挂深度与掉钩率显着相关，浅钩线切割组的钩脱落率为93.7%，而深钩线切割组的钩脱落率为71.8%。我们的结果表明，休闲捕获的美洲鳗可能对捕获和释放具有相对弹性，但建议在现场环境中验证这些结果。