Using results from a three-year mist-netting survey of bats in Michigan, we examined effects of three aspects of netting protocols on number of bats caught, relative abundance of species, species diversity, and species evenness. Netting for a second consecutive night at the same location led to a 40% reduction in number of bats captured, although relative abundance, diversity, and evenness were not affected. Proportionately fewer bats were caught during the 5th h after sunset compared with the first 4 h in a night; however, diversity and evenness were greater in the 5th h compared with the first 4 h. Diversity, evenness, and number of bats captured in nets set over wooded areas on land did not differ from nets set over water, but relative abundance differed between habitats. Even slight variations in netting protocols can lead to quantitative differences in the description of a local assemblage of bats.