Little Brown Bat

Myotis lucifugus
Family: 
Vespertilionidae (evening bats) in the order Chiroptera
Description: 

The little brown bat is a small (less than 4-inch) bat that usually roosts in caves in groups of 20, has dark glossy brown fur on its back, and has ears 5/8 inch long or less that are narrow, naked, with bluntly rounded tips. The back fur is two-toned: blackish or dark gray at the base and brown toward the tips. The wing and tail membranes and the ears are glossy dark brown. There are 6 species of Myotis in Missouri, and they require close examination to be distinguished from each other.

Size: 
Total length: 3–3¾ inches; tail length: 1¼–1¾ inches; weight: ¼ ounce.
Habitat and conservation: 
When feeding, they prefer borders between open areas and denser cover where flying insects are plentiful. Winter hibernation is in limestone caves and mines, mostly in the Ozark Highland. In spring they disperse up to 620 miles. In spring and summer the females live in nursery colonies in cliff crevices and hollow trees, under loose bark, in attics and other undisturbed retreats. Males are solitary or live in colonies up to 20 in similar protected sites, including under siding and shingles.
Foods: 
Only insects are eaten, particularly winged adult forms in flight: mayflies, mosquitoes, beetles, flies, caddis flies, lacewings, stone flies, and moths. Little brown bats feed heavily, consuming half their body weight in a night.
Distribution in Missouri: 
Widely distributed throughout the state but no longer common in any one place.
Status: 
No longer common in any one place; populations are declining.
Life cycle: 
In this species, mating is in fall before hibernation, during winter if bats become active and in spring after hibernation. The ovum undergoes no change during winter, even if the female has mated, but after hibernation ends, it is shed from the ovary and fertilization follows. Only one egg matures per year, so only a single young can be produced annually. Most young are born by mid-June and are weaned in about 6 weeks. Young are most vulnerable during the first few weeks of life.
Human connections: 
Bats help control insects, some of which are agricultural pests or are annoying to man (such as mosquitoes). Bats have contributed much to human knowledge through scientific studies of their echolocation, biology and physiology. Bats are protected by both state and federal laws.
Ecosystem connections: 
As predators, bats help to hold insect populations in balance; also, many forms of cave-dwelling life depend on the nutrients brought in by bats and released from their guano (feces).
Shortened URL
http://mdc.mo.gov/node/2920