- Scientific Name: Nycticeius humeralis
- Weight: 7-14 grams
- Wingspan: 26-28 centimeters
- Distribution: Southern Ontario, Canada, most of the eastern United States, and northeastern Mexico.
- Ecology and Behavior: This species usually inhabits buildings or tree cavities in summer. It almost never enters caves, although it sometimes joins the bats swarming about certain entrances in late summer. Maternity colonies in buildings sometimes contain hundreds of individuals. Smaller colonies may occur behind the loose bark of dead pines and in hollow cypress trees. Winter habitat is almost completely unknown, but evening bats accumulate large reserves of fat in autumn, sufficient for either hibernation or a long migration. This species emerges early and flies a slow and steady course. Heavy rain and cold temperatures retard activity, and females nursing young return to the roost periodically to care for their offspring.
- Food Habits: Probably consumes a variety of insects
- Reproduction: Young are born in nursery colonies from mid-May to mid-June. The usual litter size is two. As with most other species of bats, birth is by breech presentation. After the young are born, they grasp a nipple within 5-8 minutes. Newborns are pink, except for slightly darker feet, membranes, ears, and lips; their skin is so transparent that the viscera are visible. Lifespan is greater than 5 years.
- Status of Populations: Uncommon through most of its range, but one of the most common bats throughout the southern coastal states.
The presence of species in particular counties is based on both summer and winter occurrence records compiled by the TNBWG, an unshaded county does not represent the absence of a particular species from that county, only the lack of an occurrence record. These maps are intended for educational and general information purposes only and are not intended for use in consultation with US Fish and Wildlife Service (USFWS) or any other state or federal agencies. Project proponents should contact USFWS and the Tennessee Wildlife Resources Agency for the most up to date ranges for bat species in Tennessee.
Range Map Data Sources
National bat ranges - Layer downloaded from nationalatlas.gov. The data were compiled by Bat Conservation International using data from state natural heritage programs, published literature, unpublished reports, museum collections, and personal communications from university, Federal, State, and local biologists.
TN county occurrence data - TWRA Scientific Collection Permit data compiled from 2000-2013, TWRA Wildlife Diversity database, published literature [Graves and Harvey 1974. (Journal of the Tennessee Academy of Sciences 49:106-109)], personal communications from university, Federal, State, local biologists, and TNBWG members.