Predator identity and consumer behavior: differential effects of fish and crayfish on the habitat use of a freshwater snail
Predator identity and consumer behavior: differential effects of fish and crayfish on the habitat use of a freshwater snail
复制标题
捕食者身份和消费者行为：鱼和小龙虾对淡水蜗牛栖息地利用的不同影响
作者：
Andrew M. Turner;Shelley A. Fetterolf;Randall J. Bernot
摘要捕食者通过对猎物行为的影响，可以改变食物网其他成员之间的生态相互作用的结果。虽然众所周知，动物经常改变他们的行为与捕食风险的实施，我们知道的捕食者的其他功能如何影响猎物的行为。例如，相对较少的研究涉及捕食者身份对猎物行为的影响，但这些知识对于理解食物网相互作用至关重要。本研究对比了淡水螺类对鱼类和小龙虾捕食者的行为反应。蜗牛被放置在包含笼中鱼和小龙虾的实验性围隔中，因此实验性蜗牛与其捕食者之间的唯一交流是通过非视觉线索。笼中的鱼和小龙虾被喂以相同数量的蜗牛，从而模拟相同的猎物死亡率。在有鱼的情况下，实验蜗牛在掩护下移动，这使它们免受鱼类捕食者的伤害。然而，在小龙虾的存在下，蜗牛避开底栖生物覆盖并移动到水面。因此，两种捕食者对猎物施加相同水平的死亡率，会引起截然不同的行为反应。我们预测，这些对比鲜明的捕食风险的行为反应有重要的后果蜗牛和它们的附着生物资源之间的相互作用。
Abstract Predators can alter the outcome of ecological interactions among other members of the food web through their effects on prey behavior. While it is well known that animals often alter their behavior with the imposition of predation risk, we know less about how other features of predators may affect prey behavior. For example, relatively few studies have addressed the effects of predator identity on prey behavior, but such knowledge is crucial to understanding food web interactions. This study contrasts the behavioral responses of the freshwater snail Physellagyrina to fish and crayfish predators. Snails were placed in experimental mesocosms containing caged fish and crayfish, so the only communication between experimental snails and their predators was via non-visual cues. The caged fish and crayfish were fed an equal number of snails, thereby simulating equal prey mortality rates. In the presence of fish, the experimental snails moved under cover, which confers safety from fish predators. However, in the presence of crayfish, snails avoided benthic cover and moved to the water surface. Thus, two species of predators, exerting the same level of mortality on prey, induced very different behavioral responses. We predict that these contrasting behavioral responses to predation risk have important consequences for the interactions between snails and their periphyton resources.