Identification of Southeastern Bat Species Using Noninvasive Genetic Sampling of Individual Guano Pellets

The impact of white-nose syndrome on North American bat populations may limit the effectiveness of traditional monitoring methods, including roost surveys, mist netting, and acoustic monitoring, and, in turn, determination of bat species occurrence. Genetic markers from deoxyribonucleic acid (DNA) extracted from feces (i.e., guano pellets) may provide an effective alternative method for assessing occurrence. We used an existing genetic marker from the 16S ribosomal subunit, mitochondrial DNA, to create a DNA sequence database for the 16 species of bats known to occur in Tennessee. We used our database to identify bat species from DNA extracted from 68 guano pellets collected from accumulations found in buildings of Great Smoky Mountains National Park from May to August 2015. No bats were directly observed at 19 roost buildings (55.9% of all identified roost buildings), where genetic analysis of guano was the only method available to determine species occurrence. Two of the species we detected roosting in buildings using DNA from guano, the little brown myotis Myotis lucifugus and northern long-eared myotis M. septentrionalis, are of special concern as a result of declines from white-nose syndrome. There are no records of the northern long-eared myotis roosting in Great Smoky Mountains National Park buildings, and no records of the little brown myotis roosting in buildings since white-nose syndrome became established in Great Smoky Mountains National Park. Our findings emphasize the utility of these genetic techniques for detecting bat species when visual or acoustic methods may be compromised by species rarity, elusive behavior, or similarities in species morphology and call characteristics.