Little Brown Myotis (Myotis lucifugus)
The Little Brown Myotis is a medium-size Myotis species that measures between 70-108 mm and weighs between 6-10 g. Its fur colour is extremely variable: the fur on its back ranges from yellow or olive to blackish. The fur on its underside is lighter, varying from light brown to tan. Its dorsal fur is long and glossy. The wing membranes and ears are dark brown. The ears reach the nostrils when pushed forward; the tragus is blunt and about half the ear length. The calcar is not keeled. The skull is typical of most Myotis species; the forehead has a gradual slope.
Summer roosts are in buildings and other man-made structures, tree cavities, rock crevices, caves and under the bark of trees. In summer the sexes live separately. Females congregate in maternity colonies that may contain hundreds or even thousands of individuals. Males rarely occupy maternity colonies. In summer they can be found roosting alone or in small colonies usually in sites that are cooler than the nurseries. The Little Brown Myotis hibernates in caves and abandoned mines; it does not appear to hibernate in buildings. The Little Brown Myotis selects areas in the hibernaculum where there is high humidity (70-95%) and the temperature is above freezing (1-5°C). It may hibernate alone or in clusters. The Little Brown Myotis emerges at dusk to feed. It is an opportunistic hunter that eats a great variety of insect prey. After an initial feeding period of 15 to 20 minutes, individuals occupy temporary night roosts near the day retreat. Night roosts are used most often when temperatures are cool (below 15°C) a protected night roost may help the Little Brown Myotis remain active so that it can digest its meal faster.
Range: A widespread species, the Little Brown Myotis inhabits most of North America as far north as the tree-line. In British Columbia it is found throughout the entire mainland and on several islands, including Vancouver Island and the Queen Charlotte Islands.
Habitat: In British Columbia this bat exploits a wide range of habitats, from arid grassland and Ponderosa Pine forest to humid coastal forest and northern boreal forest. The Little Brown Myotis has the greatest range in elevation, ranging from sea level to 2288 m.