The mouse-eared bats (genus Myotis)
are easily confused and often can only be distinguished by experts.
M septentrionalis is essentially the same size and colour
as the little brown bat, but with long rounded ears and a dull brown
shoulder spot. Colour below is a buffy grey. The sexes are alike.
Average weight is approximately 7 grams (Banfield, 1974)
Distribution
Columbia Basin: Locally distributed
throughout the Cranbrook, Invermere, Golden and Revelstoke forest
districts.
British Columbia: The Northern Long-eared
Myotis has been found at a number of sites scattered through eastern,
central and northern British Columbia, including the Peace River,
Revelstoke and Liard River areas. Records not confirmed by voucher
specimens have been reported from the Cariboo region.
Global: The Northern Long-eared
Myotis is widely but sparsely distributed across forested regions
of the eastern United States and Canada north and west to the southern
Northwest Territories and eastern British Columbia.
Habitat
Throughout most of its range, the
Northern Long-eared Myotis is associated with boreal forests; in
British Columbia it is also found in the wet forests of the Interior
Cedar-Hemlock Biogeoclimatic Zone. Elsewhere in North America, day
roosts and nursery colonies have been found in buildings and under
the bark of trees.
Threats
Knowledge of range is hampered by
difficulty in identification of this and related species. There
are eight known occurrences; undoubtedly more exist. Timber harvesting
could be detrimental, since this species forages in forested habitats
and utilizes wildlife trees for nursery colonies and day roosts.
Disturbance at cave or mine hibernacula is a potential threat. Use
of chemical and biological insecticides would reduce their food
supply (Cannings et al. 1999).
Biology
This species emerges at dusk to
hunt at a height of 1-3 metres over small ponds and forest clearings
for caddisflies, moths, beetles, flies and leafhoppers. In late
summer or early autumn the bats gather to move to hibernacula, which
may be up to 56 kilometres away. The Northern Long-eared Myotis
hibernates alone or in small groups, and selects narrow crevices
where temperatures may be as low as 1.6 oC. Mating occurs
in autumn in the hibernaculum and the females store sperm over the
winter. Ovulation occurs at the time of emergence in the spring
and gestation lasts 50-60 days, after which a single young is born.
In British Columbia, limited breeding information suggests that
young are born in late June or early July (Cannings et al. 1999).
