Eastern Small-Footed Bat
(Myotis leibii Audubon and Bachman)
From: Saunders, D. A. 1988. Adirondack Mammals. State University of New York, College of Environmental Science and Forestry. 216pp
The small-footed bat has small hind feet, each about 6 mm (0.2 in) in length, but its color is even more distinctive. This golden or yellowish brown bat has black ears and a small black facial mask. Total length is 72-84 mm (2.8-3.3 in). The wingspread is 21-25 cm (8.3-9.8 in). Weight varies from 5-8 g (0.2-0.3 oz).
Range and Habitat: The range of this bat is a broad belt across North America, from southern British Columbia to northern Mexico, east through the mid-section of the Midwest, and north to southern Ontario and southwestern Quebec. Some authorities consider the western populations a separate species. In the eastern half of the range, the small-footed bat is one of the least common bats. However, in most of the mines and caves where it over-winters in the Adirondack Park, some of the populations exceed 500 individuals per site and collectively constitute about one half the individuals enumerated throughout the species’ range during winter. In spite of the species’ relative abundance in the Adirondacks, here, as elsewhere, most of its life history is unknown. The small-footed bat appears to prefer rocky, forested areas, especially near coniferous forests. In the summer, this bat roosts under rocks on talus slopes, in holes in the ground, in abandoned swallow nests, and in and around buildings.
Food and Feeding Behavior: Knowledge of the diet of the small-footed bat which forages over water, among trees, and around cliffs, comes from a few specimens whose stomachs contained beetles, bugs, ants, and flies.
Activity and Movement: The meager information about the hibernation of this species suggests a briefer dormancy period than for many species, from mid-November - April. Winter roosting sites in mines and caves are on exposed ceilings and walls, in narrow crevices, and even under rocks and within cracks on floors. Small-footed bats tolerate cold, dry, even drafty sites near cave and mine entrances, but use sites throughout these structures. Torpid individuals often hold their forelimbs in a distinctive, partially extended position.
Reproduction: Little is known about the reproduction of the small-footed bat. Females produce one young per year in mid to late summer. Maximum longevity is at least 12 years.
- Social system - Pregnant females gather in small maternal colonies of as many as 20, or roost alone. Although clusters of 50 or more may occur during hibernation, this species usually roosts in smaller groups of 4 or 5, or most often, singly.
- Communication - Unknown.
Hicks, A. 1987. In search of wintering bats. The New York State Conservationist, 41(5): 14-17, 56.
Hitchcock, H.B. 1949. Hibernation of bats in southeastern Ontario and adjacent Quebec. Canadian Field Naturalist, 62:47-59.
Hitchcock, H.B. 1955. A summer colony of the least bat, Myotis subulatus leibii (Audubon and Bachman). Canadian Field Naturalist, 69:31.
Martin, R.L. 1966. Observations of hibernation of Myotis subulatus. Journal of Mammalogy, 47:348-349.
Mohr, C.E. 1936. Notes on the least bat, Myotis subulatus leibii. Proceedings of Pennsylvania Academy of Science, 10:62-65.