Bats in the House
We are aware of having at least one and possibly more bats
living in our attic. Recently (after they have been getting lost in our
living quarters) we have begun watching at sunset to see if we can discern
where they are coming out of so that we can prepare to seal the entraces in
the late fall. While sitting in the yard at dusk, I have seen many flying
"birds" flying around the neighborhood. To me, they do not look like bats.
It seems as if a bats wings would be large and nearly as wide as it's body
is long, however these "birds" have more narrow wings and an oval body.
Are these in fact bats or is there a bird which I would commonly see at
dusk (8:00-8:30 or so in New England in August?) Also, any bat information
you can give me would be helpful. I have seen the bat(s) in the house 3
times this past couple of weeks, and because of an unfortunate incident
regarding a bat awakening me at 1:00 a.m., my entire family is in the
process of having the rabies vaccine series (myself, 4 kids). None of us
can say we were bitten, but then we were all asleep until I heard the bats
wings flapping around my head and felt him brush past my hand. In any
event, we believe the bat(s) to be big brown bats as they (it) was just
about an inch or two smaller than my palm, wings folded at his sides. I
believe I've seen at least 2 different bats since the first one had a
rather large wing span (10-12 inches, I'd say) and dark brown smooth
looking fur and the second one I saw seemed smaller and the third siting
(may have been the same bat as second siting) had a puffy furry body. Any
helpful hints would be wonderful.
I worked with bats for a number of years while a graduate student and I'm
very familar with the Big Brown Bat. Your description suggests that it may
be this species.
The "birds" flying around at dusk are probably bats. Especially if they
seem in control of their movement around trees, etc. and change direction
continually. Bat sonar location is extremely effective at night.
Bats will not attack humans. Flying around your house was very confusing
to the animal. Rabies is a concern, however, with handling literally
thousands of bats, I never experienced any problems (yes, I was innoculated
just in case.)
Search NEWTON BBS for our Nature Bulletins which has additional information.
I think it highly unlikely that you are at any risk for rabies yet, I think
you would be well aware if you had been bitten. BAts have no reason to bite
people unless trying to defend themselves when caught or frightened, so you
should be okay if you don't try to handle them. Bats can carry rabies of
course so caution is wise.
As far as identifying bats on the wing, watch the flight pattern: if the
animal makes quick left-right type turns it is probably a bat, birds
generally can dart up-down quickly but make somewhat wider horizontal
movements. In general a bat will give an impression of a much more erratic,
darting flight than birds. You might well see common nighthawks, which also
hunt insects on the wing. They have rather long pointed wings and you can
often see, if there is still enough light, a white band across the bottom of
the wings. Big brown bat is a likely identification from the description
you've given. For much more information go to:
the Bat Conservation International web site
Well, I don't know much about identification of bats, but there are plenty
of birds that will come out at dusk. Lots of insects come out at dusk, and
the birds and bats come out to eat them. The birds with narrow wings and
oval bodies sound like chimney swifts. These extremely acrobatic fliers
are sometimes mistaken for bats because of their fluttering flying motion.
Like bats, swifts can change direction in flight very quickly, making them
Unless you have a large number of bats living there, you may have a
difficult time seeing where they are leaving your house. Most likely, your
best bet will be to seal the openings you can find, searching carefully
both from the inside and from the outside of your house.
Finally, although it must be quite unpleasant, you have made the proper
choice in having your family immunized against rabies. Children have
become infected with rabies from sick bats in their rooms, without being
bitten. A bat that makes it into your living quarters is lost, and quite
likely to be rabid.
Richard Barrans Jr., Ph.D.
You may have been seeing bats, but this is a tough one to answer with
You might try visiting your local library and locating a good picture book
on bats; this would give dimensions of various bat species.
We had an interesting occurrence last week while on vacation in Europe.
While I was trying to clean our windshield from insects which has hit it,
what appeared to be an even larger insect hit the windshield and was killed,
and became caught in the wiper mechanism. Yes, it got groans from us too.
Anyway, this 'insect' actually turned out to be a small bat, but it was too
badly damaged to identify it. A good text should give enough information on
bats in your area incluing habit and diet. Good luck!
Thanks for using NEWTON!
Richard R. Rupnik
Internal Quality Auditor
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Update: June 2012