Western Washington University, Bellingham, WA, USA.
WI Department of Natural Resources, Office of Applied Science, 2801 Progress Rd, Madison, WI, 53716, USA.
Sci Rep. 2022 Jul 1;12(1):11184. doi: 10.1038/s41598-022-15200-y.
The complexities of trophic dynamics complicate the management of predator populations. Targeted culling campaigns are one management strategy meant to control predation for the benefit of the prey population. In these campaigns, individual predators are often considered "rogue" based on visitation rates to the site of concern. This definition assumes that all predators impact prey equally. However, individual variability in foraging success may compromise this assumption. To examine this hypothesis, we studied harbor seals preying on adult salmonids during the 2014-2019 fall runs in Whatcom Creek, Bellingham, Washington, USA, and recorded visitation rate and foraging success of individual seals from photographs and field observations. We then used Generalized Linear Mixed-Effects Models to model individual foraging success. Models including harbor seal identity better explained foraging success than models based on visitation rate alone. We concluded that considering intraspecific variability and classifying "rogue individuals" based on foraging success is a more accurate protocol for managing predator populations than relying solely on visitation rate of the predators.
营养动态的复杂性使捕食者种群的管理变得复杂。有针对性的扑杀活动是一种管理策略，旨在通过捕食来控制捕食者，从而有利于猎物种群。在这些活动中，个体捕食者通常根据对关注地点的访问率被视为“流氓”。这种定义假设所有捕食者对猎物的影响都是相同的。然而，觅食成功的个体差异可能会影响这种假设。为了检验这一假设，我们研究了 2014 年至 2019 年期间在美国华盛顿州贝灵汉的沃科姆克里克成年鲑鱼被捕食的港湾海豹，并通过照片和实地观察记录了个体海豹的访问率和觅食成功率。然后，我们使用广义线性混合效应模型来模拟个体觅食成功率。包含港湾海豹身份的模型比仅基于访问率的模型更好地解释了觅食成功率。我们的结论是，考虑种内变异性，并根据觅食成功率对“流氓个体”进行分类，是管理捕食者种群的一种更准确的方法，而不仅仅依赖于捕食者的访问率。
