Pace of bat die-off called historic
by Rinker Buck
December 22, 2009
(crossposted from Right of Assembly)
HARTFORD, Conn. - -- The die-off of bats across the Northeastern states is now so severe that federal wildlife officials consider it "the most precipitous decline of North American wildlife caused by infectious disease in recorded history."
Since 2006, when hibernating bats in a cave in New York state were found coated with a chalky fungus, the so-called white-nose syndrome affecting bats has hopscotched from New Hampshire to West Virginia, sometimes wiping out entire caves of bats in a single winter. Finding a remedy for the condition before the die-off reaches the huge bat habitats of Tennessee and Kentucky is considered vital because individual bats eat thousands of insects a night, providing a critical balance for nature.
This fall, biologists from Pennsylvania and New York conducted "swarming counts" of bats as they congregated before entering their hibernating caves. These surveys confirmed that many common species of bats are experiencing mortality rates of more than 90 percent.
The article goes on to referring to white-nose fungus thusly affecting little brown bats, northern long-eared bats, pipistrelle bats, and Indiana bats, already listed as endangered.
The fungus apparently functions as sufficient of an irritant to wake bats up out of hibernation, thus raising their metabolism and depleting their fat reserves too quickly for them to survive until their food supplies recover from the winter hiatus.
Game Commission Tracks White-Nose Syndrome in Bats
January 12, 2010
PR Newswire
HARRISBURG, Pa., Jan. 12 PRNewswire-USNewswire -- White Nose Syndrome (WNS) has caused cave bat population reductions in New York and New England over the past three winters. It surfaced near Albany in 2006. Pennsylvania Game Commission officials say that they are expecting cave bat mortalities this winter if the disorder spreads through hibernacula as it did New York and New England over the previous winters. To track the effects of WNS, the Game Commission is asking the public to report winter-flying bats or dead and dying bats on the landscape.
"If you're outside this winter and observe bats, we really need to hear from you," said Lisa Williams, Game Commission biologist. "While an occasional dead or disoriented bat is not unheard of in winter, we need residents to let us know if they find multiple bats outside of buildings this winter. White Nose Syndrome causes bats to fly out of their winter shelters and die on the landscape. By assisting us with surveillance, you can help us identify new die-offs so we can conduct a site investigation. Of course, commonsense safety rules apply: do not go in caves or mines or underground; do not handle bats – dead or alive; and keep children and pets away from dead or grounded bats."
There are two quick and easy ways to report sick-acting or dead bats this winter. The first is by calling the nearest Game Commission region office. The second is by using the Game Commission's "Report a Sick Bat" form that can be accessed in the right-hand column of the agency's homepage (www.pgc.state.pa.us) by clicking on "Report a Sick Bat" in the "Quick Clicks" section.
This article notes the species affected as follows: little brown bat, big brown bat, Indiana bat, eastern pipistrelle; small-footed bat, and northern long-eared bat.
The transmission of the fungus from New York to the Virginias is not considered to follow migratory paths, and thus transmission by cavers is suspected. A moratorium has been instituted on entering bat caves in affected areas.
Bat females have only one pup per year, so the current death rates are especially devastating to these populations. And since bats hibernate in large numbers and in relatively few places, disease transmission during these time periods is highly enabled.
UPDATE: Thanks for all the comments and questions. I really recommend Bat Conservation International for answers to many of them.