With Halloween just around the corner, it's very likely that a lot
of bats will be in view as part of holiday decorations. But ... most
of Pennsylvania's real bats will actually be hibernating by October
31st. During the summer, however, more than twenty-thousand of them
take up residence in the attic of an abandoned 19th-century church
near Altoona. WHYY's Brad Linder has more.
Flight of the Bat
An Old Church Offers a Haven for an Endangered Bat.
October 11, 2002
By Dan Simon
Going to church looks like it might be a lifesaver for an endangered
The Indiana Bat, on the endangered species list since 1967, has
always been picky about where it raises its young. The discovery
a few years ago that a maternal colony of the bats was making its
home in an old church in Canoe Creek State Park in Altoona, Penn.,
was big news in bat biologist circles.
The discovery is significant for several reasons. First, it means
that manmade bat habitat's may help replace some of the natural
locations the bats previously relied upon for pup rearing. The species
has suffered as its preferred forest canopy has been lost to development
in its primary range in the central part of the country. It's also
turned the old church into a research facility where biologists
have ready access to the little critter.
This old church across the road from Canoe Creek State
Park near Altoona, Penn., is home to more than 23,000 bats.
©GreenWorks photo by Dan Simon
The small bat is very similar to the much more common Little Brown
Bat. It's seen its numbers decline in Pennsylvania from thousands
of the little creatures, to fewer than a thousand. There are perhaps
a few hundred Indiana bats mingled amongst the more than 25,000
Little Brown Bats that make up the entire Canoe Creek Bat colony.
Because the church is so accessible, biologists such as Cal Butchkoski
of the Pennsylvania Game Commission have been able to learn more
about the bat's habits and preferences. This makes it more likely
they can get an accurate picture of its numbers and also how to
build better bat boxes to attract them.
An Indiana Bat. ©GreenWorks photo by Dan Simon
"The church has a black roof oriented toward the southeast,"
Butchkoski said. "It actually has two layers of roof, an old
shake shingle and over the top it, a layer of black tin and in between
those two layers is a three-quarter to one-inch crevice for them
to get into when it's real cold out and the sun is out. That heats
up just nice and easily gets up to 100 degrees on a 50 degree day."
A bat box attached to the side of the old church offers
additional roosting space for the bat colony. ©GreenWorks
photo by Dan Simon
Bats, particularly pregnant ones, need that extra warmth. The small
mammals can only store small reserves of fat necessary to sustain
life in cooler temperatures. The more calories they have to expend
to stay warm, the less that are available for fetal development.
The pregnant bats may have to slow their metabolism under such conditions,
leading to underdeveloped pups.
The church attic, which seems to have been hosting a bat colony
since the 1930s, provides the perfect place for the bats who can
move higher or lower in the attic to find the ideal temperature,
and, surprise the biologists.
"It turns out they prefer temperatures around 94 or 95 degrees,"
Butchkoski said. "So when it starts getting too warm, they
start moving down. This makes it easier for us to do an accurate
count of the Indiana bats."
The Little Brown Bats sharing the roost don't migrate downward at
the same temperature as the Indiana Bats, so instead of trying to
pick out a few hundred needles amongst a 23,000-bat haystack, biologists
can just wait until temperatures are right to do their census or
find specimens for banding or examination.