CALIFORNIA BAT - Myotis californicus

Weight: 3-5 grams.

Wingspan: 22-23 centimeters.

Distribution: Southern Alaska and western Canada south­ward through most of Mexico.

Ecology and Behavior: One of the smallest bats in the United States. Occupies a variety of habitats in the Pacific Northwest and southern and western British Columbia, from the humid coastal forest to semidesert, and from sea level to at least 1,800 meters (5,940 feet) elevation. In arid regions, it usually occurs in the vicini­ty of water. Individuals emerge shortly after sunset to for­age, which continues at irregular intervals until dawn. Its flight is slow and erratic and it hunts primarily along margins of tree clumps, around the edge of the tree canopy, over water, and well above ground in open country. California bats roost in rock crevices, hollow trees, spaces under loose bark, and in buildings. The sexes roost separately during sum­mer when females form small maternity colonies, but occur together from September to March. California bats hibernate in caves and mines.

Food Habits: The California bat feeds on small flying insects, primarily flies, moths, and beetles. Its foraging strategy consists of locating and feeding in concentrations of insects where its slow maneuverable flight allows it to capture several insects in quick succession over a short distance.

Reproduction: Breeding takes place in autumn and one baby is born in July. The potential reproductive lifespan is about 15 years.

Status of Populations: Common.

Thanks to T. L. Best, J. S. Altenbach, and M. J. Harvey for permission to reprint portions of Bats of the Western United States, 1998.