Myotis
evotis
(Long-eared Myotis)
Description:
The upper fur is brownish at the tips and dark at the base. The dark to blackish
glossy rounded ears extend past the nostrils and can exceed three-quarters of
an inch (=20mm). The tragus is extends over one-half
of the length of the ear.
Range:
A western distribution including
British Columbia east across southern Canada to Saskatchewan, south along the
western edge of the Dakotas Nebraska, much of Colorado and New Mexico, west
across northern Arizona, Nevada, to the Pacific Coast from Baja California,
through California, Oregon and Washington. It has been collected in fifteen
Idaho counties but likely occurs in most of the Gem State.
Habitat:
This bat is found in a wide range
of habitats often associated with forests. It is found under exfoliating bark,
in cavities in trees, and in stumps resulting from logging. In shrub communities,
is may be found in crevices in cliffs and rocks on the ground, in lava-tube
caves, and abandoned mines. It has also been found occasionally in buildings
and under bridges.
Found (from near sea level along Pacific Coast, to about 2830 m in Wyoming), mostly in forested areas, especially those with broken rock outcrops; also found in shrublands, over meadows near tall timber, along wooded streams, and over reservoirs. Idaho study found roosts were always located near water. Species is common in lodgepole pine forests.
Diet:
Primarily moths and beetles but other
insects including lacewings, true bugs, wasps and bees are eaten. This species
may glean insects from the surface of a variety of desert shrubs but it also
occurs and feeds in coniferous
forests.
Ecology:
In northern Idaho, long-eared myotis
appear to feed near the back of mines, especially at the portal. They do not
seem to use these mines for night roosting or winter hibernation. A few to a
moderate number of individuals are often associated with areas adjacent to reservoirs
or streams containing areas of slow-moving water. Small nursery colonies containing
females and young form. Nonbreeding small mixed sex colonies are also known
to occur during summer. More information on winter roosting ecology is needed
for this species.
Widespread and not uncommon species,
but little is known about its habits. Reportedly emerges late in evening to
feed, though some studies report earlier emergence. Forages over water or among
trees. Usually feeds by picking prey from surface of foliage, tree trunks, rocks,
or ground; may fly slowly around shrub searching for emerging moths, or perhaps
nonflying prey. Known to forage with long-legged myotis, big brown bat, silver-haired
bat, and hoary bat, but Idaho study found species foraged earlier in evening
than several other bat species. Often roosts in buildings; may also roost
in hollow trees, mines,
caves, and fissures.
Reproduction:
Swarming and mating take place
prior to hibernation
and sperm is stored over
winter. Fertilization ensues when ovulation occurs in the spring. A single pup
is born, as late as mid July in northern Idaho. Each pup weights about 20 percent
of the body mass of the female.
Mating occurs in fall; ovulation and fertilization
are delayed until spring.
Births have been recorded in mid-July in western Washington. Young and lactating
females have been recorded
in late July in New Mexico. Female and newborn young have been recorded in late
June in California. Female produces 1 young. South Dakota study found that male
young-of-year reached approximate adult size in early August.
Conservation:
![]() |
![]() |
Global Rank: | G5 |
State Rank: | S3 |
Important State References:
Bonnell,
M.L. 1967. Emergence and foraging behavior in small populations of Idaho bats.
M.S. Thesis, Univ. Idaho, Moscow. 63pp.