|The Mammals of Texas -
Chiroptera : Family
Vespertilionidae : Myotis septentrionalis (Trouessart)
Description. This is a small bat
with dull, gray-brown pelage. Compared to other Myotis
from Texas, M. septentrionalis has relatively long
ears and an unkeeled calcar. As with all Myotis,
this bat also has a narrow and sharp-pointed tragus.
Dental formula as in M. californicus.
External measurements average: total length, 78 mm; tail,
26 mm; foot, 9 mm; ear, 13 mm; forearm, 35 mm.
Distribution in Texas. Widely
distributed over eastern and northern North America, this
bat is known in Texas on the basis of only one specimen
from Winterhaven in Dimmit County. It is doubtful that
resident populations of this species occur in Texas.
Habits. This bat hibernates in
caves and mine tunnels in eastern Canada and in the
United States from Vermont to Nebraska. It is more
solitary in its habits than other Myotis,
generally found singly or in small groups of up to 100
individuals. In summer, this bat may occasionally be
found in hollow trees, rock crevices, behind tree bark,
and in buildings.
M. septentrionalis commonly
forages along forest edges, over forest clearings, and
occasionally over ponds but specific food habits remain
Little is known of the reproductive
habits of this bat. Small nursery colonies seem the rule,
and twinning may occasionally occur.