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Bats in the News - A Ray of Hope Amid White-nose Syndrome

The Fort Drum Military Installation in northern New York is home to the U.S.
Army's fabled 10th Mountain Division. It is also home to a maternity colony
of little brown myotis - and those surprisingly resilient bats are providing
a modest ray of hope amid the carnage of White-nose Syndrome, reports North
County Public Radio of Canton, New York.

Army biologists have been monitoring that colony, where females gather each
summer to give birth and raise their young, for years - well before WNS
first appeared in a single cave, also in upstate New York, in February 2006,
the radio station said.

WNS or the Geomyces destructans fungus that is its apparent cause, has now
spread to 19 states and four Canadian provinces. The total bat population of
New York and other impacted states has been decimated. Little brown myotis
have been hit so hard that scientists predict the once-common species could
be extinct in the northeastern United States within 15 years.

North County Public Radio says Chris Dobony is a Fort Drum fish and wildlife
biologist who's been studying the maternity colony. He found that, although
their numbers were drastically reduced, some of those bats survived
White-nose Syndrome, healed from the damage and may, someday, help this
battered species begin a slow recovery.

Reporter Nora Flaherty interviewed Dobony about his work.

He told Flaherty that the fungus seems to infect bats while they are
hibernating in the winter and their immune systems appear to be almost shut
down. "It doesn't seem that the fungus itself is killing the bats, but it's
causing the bats to wake up during the middle of hibernation and use fat
reserves" that are needed to get through the winter, Dobony told the radio
station. Often, the bats "end up going out on the landscape in the middle of
wintertime looking for insects, which obviously aren't there. And they will
either starve to death or freeze to death out on the landscape."

Since "we have been monitoring our little brown colony, both prior to
White-nose and after White-nose, we have some pretty good baseline
information of the impacts to the overall populations, he said. "And one of
the things that we've been able to document here is that we are getting some
survivors from White-nose. ... We have actually seen a number of individuals
survive not just one year or two years, but three and four years after being
infected with White-nose or being exposed to it. That's a really cool
finding."

In some hibernation sites hit by WNS, bat-mortality rates of up to 99
percent have been reported.

"Everybody thought that as soon you were infected, you were a dead bat,"
Dobony said, "but we are actually seeing that these guys can actually
survive it. They are healing during the summer. We are actually able to
capture some of the same individuals from the spring to the summer. We are
seeing their wings are healing.

"So there's a little bit of hope in [that] the numbers aren't crashing down
to zero in some cases," Dobony said. "In terms of recovering the species
back to historic levels, if we can get rid of White-nose or kind of put
White-nose in check, it's going to be a long time before those numbers are
back up to where they historically were."

The way back will be long and uncertain, but the Fort Drum bats offer some
hope that recovery is possible.

Bat Conservation International

 

bron: zoogmail 2011 31