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Gray Myotis (Gray Bat)

Gray Myotis (Gray Bat)

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

The gray bat is the largest of all Missouri’s myotis (mouse-eared) bats, which include the little brown myotis, the Indiana myotis, and the northern long-eared myotis. Gray bats are hard to distinguish from their myotis cousins. Gray myotises have grayer fur; it is a uniform brownish gray most of the year, turning a light rusty brown in summer. Other myotises have bi- or tricolored fur, with the tips of each strand contrasting with the base. The gray myotis’s ears and wing membranes are gray to black. Its key identifying feature is wings that attach to the ankle and not at the base of the toes. The gray bat also has a distinct notch on the inside curve of each claw.

Size: 
Length: 3 inches; wingspan: 10-12 inches; weight: 1/3 ounce.
Habitat and conservation: 
Once flourished in limestone caves, especially caves within two miles of rivers, streams, or lakes. Conservation efforts include protecting known gray myotis wintering and nursery caves from disturbance, reducing the use of pesticides (which not only affect their prey but also accumulate in the bat's tissues and mother's milk), and maintaining wooded corridors along streamsides. White-nose syndrome, a deadly fungal disease, is a new and grave threat to this species' survival.
Foods: 
Insects, including caddis flies, moths, stone flies, mayflies, flying beetles, true flies, and moths. The Asiatic oak weevil is a favorite summertime food, when it is abundant in forested cliffs along rivers. Most insects are eaten "on the wing."
Distribution in Missouri: 
Missouri contains about 20 percent of the total population of gray bats. Most of the known gray bat caves are south of the Missouri River, particularly in the Ozarks, although a few exist north of the river.
Status: 
Listed as Endangered by both the Missouri Department of Conservation and the U.S. Fish and Wildlife Service.
Life cycle: 
Pregnant females roost in maternity colonies in caves separate from males and young females from late May to June. Each female gives birth to a single young in June. The young are able to fly 4 weeks later. Mothers and young rejoin the bachelor colonies in July and August. Gray bats exhibit great loyalty to their roosting and hibernating sites and will return to the same caves year after year.
Human connections: 
Bats eats untold numbers of flying insects. It is important for people to stay out of nursery caves: If disturbed, pregnant females may abort their young and babies may drop from the wall to the floor or stream below and die. A single disturbance can wreck a colony’s reproduction for the year.
Ecosystem connections: 
Bats help control populations of flying insects. Their presence in caves is a crucial part of those unique underground ecosystems. By collecting organic material (insects) from outside the cave and bringing it in (as guano), bats help provide the basis for a variety of cave life forms.
Shortened URL
http://mdc.mo.gov/node/5032