Lost River - Karst Information Portal

2007 NSS Convention Guidebook
Eptesicus fuscus (big brown bat), roosting under a cement bridge. © Merlin D.
Tuttle, Bat Conservation International.
it was once recorded from several caves in the
state, although it has not been seen in recent
years and is probably extirpated. Any sightings
of these bats in Indiana should be reported to
the Division of Fish and Wildlife in the Indiana
Department of Natural Resources. This is
important to track behavior and movements
Corynorhinus rafinesquii (Rafinesque’s big-eared
bat), perched. © Merlin D. Tuttle, Bat
Conservation International.
272
of the species and
does not mean that
those caves will
automatically be
gated.
Now we come to
the five myotids in
Indiana. There are
17 Myotis species in
the United States,
and most are pretty
nondescript, small,
brownish bats.
Actual identification
for most can only
be determined by
experts using minute
characteristics, and sometimes only by skull
examination. However, cavers can still identify
some of these to a pretty reasonable degree
of accuracy, mostly by eliminating the species
they are not. If it seems like the bats you see are
one of the endangered species, or even a species
of concern, then you should get a professional
bat biologist to confirm your identification by
revisiting the site. Let’s start with what I consider
to be the easier species to differentiate.
The northern myotis (Myotis
septentrionalis), is a relatively easy myotid to
identify. They may be found singly or in small
clusters throughout the cave, but seem to have
an affinity for tight holes and crevices, such as in
flowstone drapery, where only the tips of their
ears and nose are visible. The most distinctive
characteristic of this bat is the length of the
ears, which are obviously much longer than
other eastern members of this genus (extending
several millimeters past the end of the nose
when laid forward). The ears have a long, sharp
tragus, the little doohickey that sticks up inside
the ear. They are fairly common in forests in the
summer, and occasionally roost in buildings
and bat houses.
The next bat to consider is the federally
Endangered gray myotis (Myotis grisescens).
Gray bats are slightly larger than other myotids,
and have dull fur. In the summer, this is
probably the only species you will find roosting