Wednesday, August 26, 2009

"Bats in Free Fall"

The title to this post, borrowed from an article in the current (September-October) issue of the Adirondack Explorer, reflects the fact that some of the heretofore commonest species of bats are in catastrophic decline in the Northeast. As reported recently by NCPR's Brian Mann who spoke with DEC biologist and bat guru Al Hicks at the annual meeting of the Adirondack Chapter of The Nature Conservancy and the Adirondack Land Trust, the decline of bats is accelerating in the Northeast and is rapidly spreading south and west. At the largest counted hibernaculum of Little Brown Bats (Myotis lucifugus) in the world, an abandoned graphite mine protected by The Nature Conservancy near Lake George, only 3,000 or so Little Brown Bats remain out of an estimated wintering population of over 200,000 bats.

Our home in Lake Placid has hosted a summer colony of Little Brown Bats for many years and as recently as three summers ago we counted over 200 bats leaving their roosts (under the eaves and in two bat houses) in the late evening. This summer we have not seen more then 2 bats emerge, a 99% decline similar to that reported by Al for the graphite mine hibernaculum. (Anyone who has data on the numbers of bats roosting in their home or other buildings is urged to report their data to the US Fish & Wildlife Service's office in Concord, NH.)

The most likely culprit appears to be a white fungus, recently described and aptly named Geomyces destructans, which appears on the nose, ears, and wing and tail membranes of infected bats. The fungus causes swelling and scaring and may cause the bats to arouse prematurely (and fatally) from hibernation and attempt to forage for food long before food is available and in freezing temperatures to which bats are not adapted. There is speculation that the fungus was brought here from Europe where bats infected with the same or a similar fungus exist in much lower numbers and density compared to bats in North America.

After its initial detection in the Albany area just three years ago, white-nose syndrome has appeared in bats from Maine to southwestern Virginia. Bats routinely travel long distances and there appears to be no way to stop or even slow the spread of this bat-killing pathogen, although scientists are desperately trying to do so. Bats play critical ecological roles in insect control, plant pollination, and seed dissemination. The potential catastrophic decline of North American bat populations would have serious ecological consequences, and the possible loss of entire species would be irreparable.

For an exerpt of Brian Mann's interview with Al Hicks, part of NCPR's continuing coverage of this unfolding tragedy, see Also see The US Fish and Wildlife Service white-nose syndrome web site at

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