Molecular diet analysis has disclosed how incredibly species-rich insectivorous bat diets can be. In this study, Jodi Sedlock, Frauke Krüger and Beth Clare found molecular evidence of 655 different arthropod species in the diets of just four bat species from the Philippines. A comparative analysis of the diets of Rhinolophus inops, Rhinolophus arcuatus, Rhinolophus virgo and Hipposideros pygmaeus revealed significant diet overlap, despite distinct differences in traits such as total body mass, wing loading, forearm length, and peak frequency of echolocation call. Moreover, geographical location influenced the types of prey likely to be consumed by a population—diets of one species were more similar to other sympatric species than to conspecifics from a different island. One of the most fascinating trends observed was the inverse relationship between body mass to number of prey species consumed; the smallest bat, H. pygmaeus, actually displayed the broadest niche. Significant niche breadth and high diet overlap incites curiosity as to alternative mechanisms of niche specialization among these insectivorous bat species.
Sedlock, J. L., F. Krüger, and E. Clare (2014) Island bat diets: does it matter more who you are or where you live? Molecular Ecology DOI: 10.1111/mec.12732
http://onlinelibrary.wiley.com/doi/10.1111/mec.12732/abstract