Simulated trapping and trawling exert similar selection on fish morphology

Commercial fishery harvest can influence the evolution of wild fish populations. Our knowledge of selection on morphology is however limited, with most previous studies focusing on body size, age and maturation. Within species, variation in morphology can influence locomotor ability, possibly making some individuals more vulnerable to capture by fishing gears. Additionally, selection on morphology has the potential to influence other foraging, behavioural, and life-history related traits. Here we carried out simulated fishing using two types of gears: a trawl (active gear) and trap (a passive gear), to assess morphological trait-based selection in relation to capture vulnerability. Using geometric morphometrics, we assessed differences in shape between high and low vulnerability fish, showing that high vulnerability individuals display shallower body shapes regardless of gear type. For trawling, low vulnerability fish displayed morphological characteristics that may be associated with h...

商业捕捞可影响野生鱼类种群的演化进程。然而目前我们对形态学选择的认知仍较为有限，既往多数研究仅聚焦于体型、年龄与成熟度。在物种内部，形态差异可影响鱼类的运动能力，进而可能使部分个体更易被渔具捕获。此外，针对形态学的选择还可能影响鱼类的觅食、行为以及生活史相关的其他性状。本研究采用两类渔具开展模拟捕捞实验：拖网（trawl，主动式渔具）与陷阱（trap，被动式渔具），以评估与捕获易感性相关的基于形态性状的选择作用。本研究利用几何形态测量法（geometric morphometrics）对比了高、低捕获易感性鱼类的形态差异，结果显示无论使用何种渔具，高易感性个体均呈现更浅的躯体形态。针对拖网捕捞而言，低易感性鱼类呈现出可能与……相关的形态特征