This study characterizes the composition, structure, and dynamics of arthropod communities associated with bat guano deposits in buildings. Guano beneath three summer roosts of the little brown bat (Myotis lucifugus) in southern New Hampshire was sampled over a 1-year period.Twelve arthropod species are reported of which most are cosmopolitan associates of dried organic matter and stored products. Included are psocopterans, beetles, mites, hemipterans, a flea, and a pseudoscorpion. These taxa function as fungivores, sarcophages, predators, and ectoparasites.These simple arthropod communities exploit a seasonally rich resource produced by roosting bats. Nycteriglyphine mites were the first free-living colonizers of fresh guano deposits and were the most numerous arthropods throughout the year. Older guano deposits and those with the most diverse resource base generally supported the greatest number of species.Seasonal changes in communities included the presence of fleas only when bats were present, a greater number but lower diversity of other arthropod species when bats were present, and a more equitable distribution and abundance of species when bats were absent. Fresh, wet guano supported higher densities of fungivorous mites and flea larvae than did older, drier guano.
