Silver-haired Bat (Lasionycteris noctivagans)
The scientific name of the silver-haired bat is derived from Greek and Latin words meaning "Night wandering shaggy bat." This medium-sized bat may be familiar to fly fishermen who cast their trout flies above Michigan's trout streams in the late afternoon. The silver-haired bat prefers to forage along wooded streams, and may even try to pick off your favorite fly pattern. They can be found along both the cold water streams of the north and warmer streams of southern Michigan.
During the summer, these bats live as single individuals. The bats seen clustered in buildings and other structures are most likely little brown or big brown bats. Silver-haired bats spend the daylight hours in seclusion under bark, in bulky birds nests, woodpecker holes, or other tree hollows.
The coloration of their fur looks as if they have just returned from the hair stylist. The brown-to-black hair appears as if it has just been frosted with silvery tint. The tinting does not extend to the head or neck.
Silver-haired bats have been found all across the state during the summer time. During the fall, groups of mixed sexes can be found. Courtship and mating occur during the migratory period. They form winter colonies and hibernate in the southern part of their range. They return again in spring when females give birth to one or two young.
Conservation of silver-haired bats will depend on maintaining clean healthy rivers. Most of their diet depends on insects that spend part of their time in the water. Having a healthy diet, free of contaminants, is a key to reproducing offspring. Maintenance of river flood plain forests will also be important to provide roosting areas for these masters of the evening skies.
Lasionycteris noctivagans (University of Michigan, Museum of Zoology)