Between-habitat distributions of prey shared by multiple predators depend on habitat use by the predators, whose own distributions may interact. We used a large-scale, whole-system natural experiment to examine distributions of anuran tadpoles and insect predators between pond microhabitats with contrasting complexity (open water vs emergent littoral vegetation) in drainable ponds that were either kept fishless or stocked with fish. Total relative densities of insect predators did not significantly differ with respect to the fish status of the ponds. Individual anuran taxa responded variously, but only fish-tolerant Bufo bufo densities were higher in the presence of fish. The densities of both insect predators and tadpoles showed positive interactions between fish presence and the use of complex littoral habitat. The habitat shift to littoral vegetation could be indirectly amplified by fish adverse impact on submerged macrophytes, the main structured microhabitat in open-water areas. Irrespective of mechanisms of fish effects (direct consumption, behavioral deterrence or alteration of habitat conditions), aggregation of both tadpoles and insect predators in littoral vegetation may put tadpoles at greater risk of predation by insects, a potentially important factor of amphibian mortality in waters containing fish.

中文翻译：

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池塘蝌蚪及其昆虫捕食者对鱼类存在的反应的栖息地分布

多个捕食者共享的猎物的栖息地间分布取决于捕食者对栖息地的使用，它们自己的分布可能会相互作用。我们使用大规模的全系统自然实验来检查无尾蝌蚪和昆虫捕食者在具有对比复杂性（开放水域与新兴沿岸植被）的可排水池塘中的池塘微生境之间的分布，这些池塘要么保持无鱼，要么放养鱼类。昆虫捕食者的总相对密度与池塘的鱼类状况没有显着差异。个体无尾猿分类群的反应各不相同，但只有鱼类耐受的蟾蜍密度在有鱼的情况下更高。昆虫捕食者和蝌蚪的密度表明鱼类的存在与复杂的沿海栖息地的使用之间存在积极的相互作用。鱼类对水下大型植物的不利影响可能会间接放大栖息地向沿海植被的转变，水下大型植物是开放水域的主要结构化微生境。不考虑鱼类效应的机制（直接消费、行为威慑或栖息地条件的改变），蝌蚪和昆虫捕食者在沿海植被中的聚集可能使蝌蚪面临更大的被昆虫捕食的风险，这是导致水域中两栖动物死亡的潜在重要因素鱼。