Monk Christopher Thomas, Arlinghaus Robert
Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
Division of Integrative Fisheries Management, Department of Crop and Animal Sciences, Faculty of Life Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.
PLoS One. 2017 Mar 16;12(3):e0173989. doi: 10.1371/journal.pone.0173989. eCollection 2017.
Fish personality traits, such as swimming activity, or personality related emergent behavioural properties, such as the degree of space use shown by an individual fish, should affect encounter rates between individual fish and fishing gear. Increased encounters should in turn drive vulnerability to capture by passively operated gears. However, empirical evidence documenting a relationship between activity-based behaviours and vulnerability to capture by passive fishing gear in the wild is limited. Using whole-lake acoustic telemetry, we first documented significant repeatabilities over several months in a suite of encounter rate-associated behaviours (swimming distance, activity space size, time on baited feeding sites, switching frequency among baited feeding sites, distance to the lake bottom) in two recreationally important benthivorous cyprinid species, the common carp (Cyprinus carpio) and tench (Tinca tinca). We then experimentally targeted both species using stationary angling on baited feeding sites. Individual fish regularly visited the angling sites, documenting that the fishes encountered the angling baits. When attempting to explain individual variation in vulnerability as a function of repeatable behavioural traits, we found no evidence of a significant relationship among various encounter-based behaviours and vulnerability to angling for both species. There was also no evidence for size selection or for energetically less conditioned fish to be more vulnerable. The data cumulatively suggest that fine-scale behaviours after encountering a bait (e.g., frequency of bait intake) may be ultimately decisive for determining vulnerability to angling in benthivorous fish. Based on our work, fishing-induced selection on encounter-based behaviours in recreational angling for benthivorous fish in the wild appears unlikely.
鱼类的个性特征,如游泳活动,或与个性相关的新兴行为特性,如个体鱼所表现出的空间利用程度,应该会影响个体鱼与渔具之间的相遇率。相遇率的增加反过来会增加被被动操作渔具捕获的易感性。然而,记录野生环境中基于活动的行为与被动渔具捕获易感性之间关系的实证证据有限。通过全湖声学遥测,我们首先记录了两种具有重要休闲价值的底栖鲤科鱼类——鲤鱼(Cyprinus carpio)和丁鱥(Tinca tinca)——在几个月内一系列与相遇率相关行为(游泳距离、活动空间大小、在诱饵喂食点停留的时间、在诱饵喂食点之间的切换频率、到湖底的距离)的显著重复性。然后,我们在诱饵喂食点使用固定钓法对这两个物种进行了实验。个体鱼定期光顾钓鱼点,证明鱼遇到了鱼饵。当试图将易感性的个体差异解释为可重复行为特征的函数时,我们没有发现这两个物种的各种基于相遇的行为与垂钓易感性之间存在显著关系的证据。也没有证据表明存在大小选择或能量状况较差的鱼更容易被捕的情况。这些数据累积表明,遇到鱼饵后的精细行为(例如,吞食鱼饵的频率)可能最终对决定底栖鱼类的垂钓易感性起决定性作用。基于我们的研究,在野外休闲垂钓中,钓鱼对底栖鱼类基于相遇的行为进行诱导选择似乎不太可能。