Southeastern Myotis

(Myotis austroriparius)

Southeastern myotis in summer by John MacGregor
Southeastern myotis in summer by John MacGregor

Kentucky Status:  Endangered

Description:  The southeastern myotis is a medium-sized bat, measuring 3½-4 inches in length with a wingspan of about 10 inches. Bats in the genus Myotis are relatively hard to tell apart, but this species typically has whitish belly fur in winter that contrasts strongly with the brown fur of the back making it easily distinguishable. Its fur actually has a wooly appearance and typically takes on a russet hue in summer. The species is also characterized by long toe hairs, and a bare, pinkish nose.

Range:  This bat occurs locally through the southeastern United States from southeastern North Carolina, central Georgia, southern and western Alabama, western Tennessee and Kentucky, southern Indiana and Illinois, west to central Arkansas, southeastern Oklahoma, and eastern Texas, south to the Gulf Coast and central Florida.

Kentucky Occurrence Summary:  The southeastern myotis can be found regularly only in the western half of Kentucky, and even there it is very locally distributed.

Distribution in Kentucky:  See map

Habitat and Life History:  This bat uses a variety of roost sites across its range, typically roosting in clusters of several to a few hundred or more individuals. In Kentucky it occurs throughout the year, typically hibernating in caves, often in association with Indiana bats. From about mid-April to late October, some continue to roost in caves, but many may move into cavities in large, hollow trees typically associated with bottomland habitats, often near water. Kentucky’s first known maternity colony was found to be using a cave but in more recent years, use of hollow trees has been documented. In other parts of its range, it has been observed using abandoned buildings in addition to caves and hollow trees. Southeastern bats are thought to forage primarily over lakes, ponds and slow-moving streams, flying close to the water’s surface. This species is unique among Kentucky’s Myotis bats in that it normally bears twins instead of a single young. Young take two to three weeks longer to develop than most of our other bat species.

Threats:  One primary threat to the southeastern myotis is the loss and degradation of mature bottomland hardwood forests due to agricultural conversion and urban expansion. Habitat alteration has greatly reduced the amount of suitable summer roosting and foraging habitat for the species. Even clearing of mature upland forests is seen as a threat. Since the species can use caves as hibernacula or maternity sites, it is also subject to human disturbance. Hibernating bats can be awakened by excessive human visitation, causing the bats to use up important fat reserves. Disturbance to maternity sites can cause the bats to move to a less suitable site. The indirect effects of pesticide use on this insectivorous bat are not known, but likely have played a role as well. In addition, southeastern myotis are susceptible to white-nose syndrome, a devastating disease that has caused unprecedented mortality in some of our hibernating bat species, especially in the northeastern U.S.

Hibernating cluster of southeastern myotis
Hibernating cluster of southeastern myotis
Photo by John MacGregor