River otter (Lontra canadensis) populations in North America have been the focus of significant restoration efforts. Wildlife management agencies, concerned about the unintentional take of river otters incidental to beaver (Castor canadensis) trapping, may recommend techniques to avoid capturing river otters. River otter avoidance techniques that are ineffective or diminish trap performance for beavers are undesirable. We conducted a field evaluation in 2015 and 2016 in Wisconsin to assess how two trigger configurations (offset and center) on body-grip traps would affect the incidental capture rate of river otters during beaver trapping. We also evaluated effects of each configuration on beaver capture rates, body lengths, and anatomical locations of trap-jaw strikes. We used size 330 body-grip traps equipped with identical triggers and alternated between trigger configurations during beaver damage management activities. We captured 8 river otters with each trap trigger configuration. Trap-jaw strikes on beavers differed between trigger configurations, with offset triggers resulting in more abdomen strikes and center triggers causing more cervical vertebrae strikes. We found that an offset trigger configuration did not reduce incidental take of otters and was less effective for trapping beavers. © 2021 The Wildlife Society. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

中文翻译：

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用于减少河獭对海狸诱捕的偶然性的身体抓握式诱捕器触发器配置的评估

北美的河獭 ( Lontra canadensis ) 种群一直是重大恢复工作的重点。野生动物管理机构担心无意中捕获与海狸 ( Castor canadensis) 相关的河獭) 诱捕，可能会推荐避免捕获河獭的技术。对海狸来说无效或降低陷阱性能的河獭回避技术是不可取的。我们于 2015 年和 2016 年在威斯康星州进行了实地评估，以评估身体抓握陷阱上的两种触发配置（偏移和中心）如何影响海狸诱捕期间河獭的偶然捕获率。我们还评估了每种配置对海狸捕获率、体长和陷阱颚撞击的解剖位置的影响。我们使用了配备相同触发器的 330 号身体抓握陷阱，并在海狸损害管理活动期间交替使用触发器配置。我们使用每个陷阱触发器配置捕获了 8 只河獭。海狸的陷阱下颚撞击因触发器配置而异，偏移触发器导致更多的腹部撞击和中心触发器导致更多的颈椎撞击。我们发现偏移触发器配置并没有减少水獭的偶然捕获，并且对捕获海狸的效果较差。© 2021 野生动物协会。本文由美国政府雇员提供，他们的工作在美国属于公共领域。