Canadian Journal of Fisheries and Aquatic Sciences, Ahead of Print.
In mixed fisheries where multiple species are caught, to manage resources sustainably, knowledge about the species-specific vulnerability to fishing is equally or even more important than knowledge of size selectivity of the gear. We compared the vulnerability to bait recreational angling in four salmonid species in natural streams in Japan. The ranking of species-specific angling vulnerability was as follows (from highest to lowest): rainbow trout (Oncorhynchus mykiss), masu salmon (Oncorhynchus masou), white-spotted char (Salvelinus leucomaenis), and southern Asian Dolly Varden (Salvelinus curilus). In all species, larger individuals were more vulnerable to angling, but there were differences in the size dependence between species. In rainbow trout and Dolly Varden (which have a nonanadromous life history in the study area), the probability of being caught monotonically increased with body size, while the vulnerability to angling in masu salmon and white-spotted char (which have an anadromous life history in the study area) showed a domed-shaped pattern. We found that across the species the catch per unit effort showed a hyperstable relationship with population density. Therefore, diminishing local populations are prone to collapse, and this collapse would be hard to foresee based on catch rate data alone.

中文翻译：

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同域流鲑鱼中特定物种的垂钓脆弱性及其大小选择性

加拿大渔业和水产科学杂志，提前印刷。
在捕获多种物种的混合渔业中，为了可持续地管理资源，了解特定物种对捕鱼的脆弱性与了解渔具的尺寸选择性同等甚至更重要。我们比较了日本天然溪流中四种鲑鱼物种对诱饵休闲垂钓的脆弱性。特定物种的垂钓脆弱性排名如下（从高到低）：虹鳟鱼（Oncorhynchus mykiss）、马苏鲑鱼（Oncorhynchus masou）、白斑鲹（Salvelinus leucomaenis）和南亚多利鱼（Salvelinus curilus） . 在所有物种中，较大的个体更容易受到钓鱼的影响，但物种之间的大小依赖性存在差异。在虹鳟鱼和 Dolly Varden（在研究区有非溯河生活史）中，被捕获的概率随着体型的增大而单调增加，而马苏鲑鱼和白斑鲱（在研究区具有溯河生活史）的钓鱼脆弱性则呈圆顶状。我们发现，在整个物种中，单位努力的捕获量与种群密度呈超稳定关系。因此，减少的当地人口很容易崩溃，而仅根据捕获率数据很难预见这种崩溃。