Eastern Small-Footed Myotis

(Myotis leibii)

Eastern small footed myotis
Eastern small-footed myotis by John MacGregor

Kentucky Status:  Threatened

Description:  One of Kentucky’s two smallest bats and the smallest member of the genus Myotis, this bat barely reaches 3 inches in length. It weighs about the same as a nickel and has a wingspan of less than 9 inches. As its name implies, in addition to being small, this bat has especially small feet relative to its body size. The species has medium brown fur on the upperparts and is slightly lighter and buffier on the belly. The face and ears are typically dark brown or blackish, giving a unique “black-masked” look. The calcar has an obvious keel.

Range: The species is locally distributed in the eastern United States and southern Canada from southern Maine and southern Ontario, southwestward through the Appalachian Mountains and westward to southern Illinois and Missouri, southeastern Oklahoma, central Arkansas and central Tennessee.

Distribution in Kentucky:  See Map

Kentucky Occurrence Summary:  The species is mostly associated with massive cliff line habitats found in the eastern part of the state in the Cumberland Plateau and Cumberland Mountains but also in the Mammoth Cave Plateau and the Kentucky River Palisades.  

Habitat and Life History:  Small-footed myotis use a variety of roost sites throughout the year. In winter, most are found in caves but many may occur in rock shelters and fissures in cliffs, and there are several records of them using old mines and quarries. They are usually found singly, wedged back into a recessed area in the rock. Despite their small size, these bats seem to prefer cold sites, just above freezing, as hibernation sites. During summer, the species has been reported using abandoned buildings, bridges (especially in the expansion joints), rock shelters or fissures along clifflines and even talus slopes just beneath the rocks. During the summer, small-footed myotis roost both singly and in small groups of up to about 20 individuals; the latter being maternity colonies where females have gathered together to have their young. Little is known of this bat’s foraging behavior, but the species presumably forages primarily in the vicinity of forest and forest edge.

Threats:  So little is known about the habits of the small-footed myotis that researchers aren’t really sure if they have declined in abundance over time. They are found in such small numbers in most areas, that local impacts to hibernacula and summer roost sites do not have as significant an impact on their overall population. This bat has been considered by some biologists to be associated with extensive areas of mountainous forest. Thus, it may be that the conversion of forested habitats to farmland and settlements has decreased the amount of preferred habitat in some areas, but the species has adapted to bridges and uses a host of other roosting sites as well. Small-footed myotis are now 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.

Eastern small-footed myotic in bridge crevice
Eastern small-footed myotis in bridge crevice
Photo by James Kiser

 

Eastern small-footed myotis Eastern small-footed myotis
Photo by John MacGregor
 
Eastern small-footed myotis Eastern small-footed myotis
Photo by John MacGregor