Silver-haired Bat (Lasionycteris noctivagans) 



Description: This bat can be distinguished from all other bats in the Northern Great Plains by 

 its distinctive coloration. The dorsal pelage is long and blackish brown, "frosted" with 

 silvery white. Membranes are blackish brown, ears are short (12-17 mm), rounded, 

 and naked. The dorsal surface of the uropatagium is furred. Weighs 8-12 g. 



Distribution: Occurs throughout much of the United States and southern Canada north to 

 southeastern Alaska and south to northern Mexico 



Habitat and Habits: Found in a variety of forested habitats, sometimes in open country 



associated with stands of trees; preferably near ponds and streams. Few summer roost 

 sites have been described, but probably roosts behind bark or in tree cavities. This bat 

 is more common in buildings in autumn during migration. Hibernacula include tree 

 cavities, rock crevices and buildings, infrequently in mines or caves. One torpid 

 individual was found in a cave in November in the Black Hills (Turner 1974). This 

 species is solitary, so it is rarely found in groups with more than 3-4 individuals. 

 Mating occurs in autumn, and the young are usually born in June. Single pregnant 

 females were collected on 1 June in the Slim Buttes (Andersen and Jones 1971) and on 

 12 June in the Black Hills (Turner 1974). Volant young and lactating females were 

 caught in mid-July in the Long Pines (Jones et al. 1973). Emerges early in the evening 

 to forage around street lights, among trees, and around standing water in a slow 

 leisurely pattern low over the ground. In 1994, this species was detected on 13 June at 

 Road Draw Spring #1, Slim Buttes, near a pond on 14 June in the Ekalaka Hills, on 15 

 June in the SE corner of the Long Pines, and on 28 September at Dry Creek Reservoir, 

 South Cave Hills (Appendix B3). 



Status: Considered a common summer resident in the Long Pines (Jones et al. 1973), and 

 probably locally common in other Sioux District units. Most individuals probably 

 migrate out of the region in autumn, as winter records are restricted to one hibernating 

 individual in the Black Hills in November (Turner 1974). This species has been 

 recorded from Ekalaka Hills, the Long Pines, North Cave Hills, South Cave Hills, and 

 Slim Buttes (Appendix B4). The Silver-haired bat is not listed by any federal agency. 



Natural Heritage Program rank: G5; not on Montana Species of Special Concern list, S4 in 

 South Dakota. 



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