Data from: Eating local: influences of habitat on the diet of little brown bats (Myotis lucifugus)

We employ molecular methods to profile the diet of the little brown bat, Myotis lucifugus, and describe spatial and temporal changes in diet over their maternity season. We identified 61 prey species of insects and 5 species of arachnid. The largest proportion of prey (∼32%) were identified as species of the mass-emerging Ephemeroptera (mayfly) genus Caenis. Bats roosting in agricultural settings had lower dietary richness than those occupying a roost located on a forest fragment in a conservation area. We detected temporal fluctuations in diet over the maternity season. Dipteran (fly) species dominated the diet early in the season, replaced later by species of mayfly. Because our methodology provides species-level identification of prey, we were able to isolate environmental indicator species in the diet and draw conclusions about the location and type of their foraging habitat and the health of these aquatic systems. The species detected suggested that the bats use variable habitats; members of one agricultural roost foraged on insects originating in rivers or streams while those in another agricultural roost and the forest roost fed on insects from pond or lake environments. All source water for prey was of fair to good quality, though no species detected are intolerant of pollution thus the habitat cannot be classified as pristine. Our study outlines a model system to investigate the abiotic and biotic interactions between habitat factors through this simple food chain to the top predator.

本研究采用分子生物学方法对小棕蝠（Myotis lucifugus）的食性进行解析，并刻画其繁殖季内食性的空间与时间动态变化。本次研究共鉴定出61种昆虫猎物与5种蛛形纲动物（arachnid）猎物。占比最高的猎物（约32%）被鉴定为集中羽化的蜉蝣目（Ephemeroptera）细蜉属（Caenis）物种，该目昆虫俗称蜉蝣（mayfly）。栖息于农业生境的蝙蝠，其食性物种丰富度低于栖息于保护区内森林片段巢穴的蝙蝠。本研究观测到繁殖季内蝙蝠食性存在时间波动：繁殖季早期，双翅目（Diptera）物种为食性主导类群，该目昆虫俗称蝇类，后续则被蜉蝣物种取代。由于本研究方法可实现猎物的物种级鉴定，我们得以从食性组分中分离出环境指示物种，并据此推断蝙蝠觅食栖息地的位置与类型，以及对应水生生态系统的健康状况。所检测到的猎物物种表明，蝙蝠可利用多种不同类型的生境：一处农业栖息点的蝙蝠以河流或溪流来源的昆虫为食，而另一处农业栖息点与森林栖息点的蝙蝠则取食池塘或湖泊环境中的昆虫。尽管所有猎物的来源水体水质均处于中等至良好水平，但本次研究未检测到任何对污染不耐受的物种，因此该栖息环境无法被归类为原生未受干扰的洁净状态。本研究建立了一套研究模型，可依托该简单食物链，探究栖息地因子与顶级捕食者（top predator）之间的非生物（abiotic）与生物（biotic）交互作用。