Genetic markers offer multiple approaches to infer prey consumption by forest-dwelling bats

Genetic techniques are becoming increasingly viable options for investigating food habits of cryptic predators. To compensate for the current lack of resolution regarding the food habits of forest-dwelling bats, we are developing and utilizing DNA markers across a gradient of prey specificity, thus enhancing our ability to identify dietary components relative to traditional morphological identification. Using universal insect primers, we have amplified and sequenced DNA fragments from Cytochrome c Oxidase I in 123 fecal samples of 62 northern bats, Myotis septentrionalis, captured in mist nets in eastern deciduous forests. We have built a library of 152 DNA sequences of 86 commonly occurring species of Lepidoptera, allowing direct comparisons of sequences from fecal samples with that of potential prey species using neighbor-joining tree and Bayesian analyses. Using web-based BLAST, fecal samples most consistently match sequence entries for Coleoptera, Diptera, and Lepidoptera, affirming the importance of these broad prey groups to our model predator. Additionally, we are using our sequence library to develop species-specific DNA primers to test for the consumption of specific lepidopteran species. Though the northern bat is a commonly-occurring species, numerous bat species in North America are of concern or in decline. Our research suggests that prey consumed by bats may be inferred multiple ways using these novel techniques. Continued development of these techniques will increase our understanding of the trophic linkages between bats and insects, and provide a means of evaluating the effects of forest disturbance on bat populations, further enhancing attempts at stewardship and conservation.