Winkelman Dana L, Aho John M
Department of Zoology and Savannah River Ecology Laboratory, University of Georgia, 30602, Athens, GA, USA.
Oecologia. 1993 Dec;96(3):300-303. doi: 10.1007/BF00317497.
Predation can have strong direct and indirect effects on the behavior of prey. We investigated whether predation by chain pickerel (Esox niger) caused adult eastern mosquitofish (Gambusia holbrooki) to alter their habitat use and whether pickerel predation influenced survival of adult and neonate mosquitofish. The number of adult mosquitofish using the riskier of three habitats was lowest when two predators occupied the risky habitat, intermediate in the treatment with one predator, and highest when no predators occurred there. More mosquitofish neonates survived high predation treatments than treatments lacking pickerel. We conclude that pickerel predation causes adult mosquitofish to shift to refuge habitats. The pattern of neonate survival suggests that adult habitat use may create a refuge from cannibalism for neonate mosquitofish, resulting in higher neonate survival in treatments with more pickerel. Hence, pickerel predation has a direct effect on adult mosquitofish behavior and a strong indirect effect on neonate survival. Both interspecific and intraspecific predation can effect prey populations and can interact to produce important indirect effects.
捕食对猎物的行为会产生强烈的直接和间接影响。我们研究了链鲈（Esox niger）的捕食是否会导致成年东部食蚊鱼（Gambusia holbrooki）改变其栖息地利用方式，以及链鲈的捕食是否会影响成年和新生食蚊鱼的生存。当两个捕食者占据风险较高的栖息地时，使用三种栖息地中风险较高栖息地的成年食蚊鱼数量最少；在有一个捕食者的处理中数量处于中间水平；当该栖息地没有捕食者时数量最多。与没有链鲈的处理相比，更多的食蚊鱼幼鱼在高捕食处理中存活下来。我们得出结论，链鲈的捕食会导致成年食蚊鱼转移到避难栖息地。幼鱼的生存模式表明，成年食蚊鱼的栖息地利用可能为食蚊鱼幼鱼创造了一个免受同类相食的避难所，从而使在有更多链鲈的处理中幼鱼的存活率更高。因此，链鲈的捕食对成年食蚊鱼的行为有直接影响，对幼鱼的生存有强烈的间接影响。种间和种内捕食都会影响猎物种群，并且可能相互作用产生重要的间接影响。
