USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

North Dakota's

Federally Listed Endangered, Threatened, and Candidate Species – 1995

Long-eared Myotis (Myotis evotis)

GIF -- species photo gif--species map

Note: If you have a photo of this species that you feel would be appropriate for this resource, please contact us at All photos will be properly credited and will remain the property of the photographer.

Status: Former Candidate (Note: As of February 28, 1996, this species is no longer listed as a Candidate species. However, it remains a species of management concern.)

Historical Status:
The long-eared myotis' historical range is believed to be similar to its present range, however, throughout its range, its abundance and distribution is suspected to be in decline.

Present Status:
This long-eared bat ranges over much of temperate western North America, from southern Canada southward to the highlands of Arizona, New Mexico, and southern California. In the Great Plains, it is known only from western North Dakota and northwestern South Dakota. Two subspecies of Myotis evotis are recognized. Myotis evotis evotis occupies most of the range including the Great Plains.

The long-eared myotis favors wooded areas, principally coniferous or oak forests, near rocky bluffs or canyons. In the Dakotas it seems primarily limited to pine-covered scarps and other broken terrain. By day, this bat roosts singly or in small clusters in buildings and perhaps under tree bark; night roosts are sometimes in caves. These bats emerge at late dusk or after nightfall to forage among trees or over water. In the Dakotas, several other species of myotis, big brown bats, hoary bats, and silver-haired bats frequent the same foraging areas. It feeds heavily on small moths and also eats flies, beetles, and other insects.

Life History:
Less is known of its biology than that of most other American members of the genus. Females apparently form small maternity colonies of 10 to 30 bats in buildings. A single young is produced, but little else is known about the reproduction of this species. As in other temperate bats, there is a single molt annually, which takes place in July and August.

Aid to identification:
A relatively large species among those inhabiting the Northern Great Plains, the long-eared myotis has the largest ears of any American myotis, and when laid forward the ears extend 1/4" (7 mm) beyond nose. Its ears are dark, usually black and its fur is long and glossy, ranging from light brown to brown in color. Total length, 3-3 3/4" (75-97 mm); ears, 1" (22-25 mm); tail, 1 3/8-1 3/4"(36-46 mm); hindfoot, 1/4-3/8" (7-10 mm); forearm, 1 3/8-1 5/8" (35-41 mm); wingspread, about 10.8" (27.5 cm); weight approximately 0.25 ounce.

Reasons for decline:
Present and threatened destruction of habitat may be the most important factor concerning the existence of this bat. They are extremely vulnerable to mine closures, and the effects of disturbance from recreation at these sites. Pesticides and other environmental contaminants destroy their prey base. Bats are also known for loading of pesticides in their fat reserves.

Notify a natural resources agency on any suspected long-eared myotis sightings.

Myotis is derived from two Greek words, mys, "mouse" and otos, "ear," in reference to the fact that the ears of many common bats resemble those of mice. Evotis means "good ears" and pertains to the conspicuous ears of this bat and is of Greek origin.

Myotis evotis in Mammalian Species No. 329, pp. 1-5. by R.W. Manning and J. K. Jones Jr. Mammals of the Northern Great Plains by J. K. Jones Jr. et. al, 1983.

Previous Species -- Pale Townsend's Big-eared Bat
Return to Contents
Next Species -- Long-legged Myotis

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 07:20:06 EST
Sioux Falls, SD [sdww55]