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| Myotis lucifugus |
Biologists are gearing up for the winter bat count, but they expect more bad news as the
"white nose syndrome" continues to spread through North America's bat colonies. The
cause has been isolated,a fungus
(Geomayces destructans)that lives in cave soil, but no effective means have been developed to stop the virus from killing more beneficial bats. The state of Wisconsin considers the fungus to be an invasive species, perhaps transplanted to New World hibernacula by peripatetic spelunkers. Estimates of the death toll are between 5.7 and 6.7 million. Mortality rates in some caves reach 100%. 70-80% is common. Congress directed the Department of Interior to dedicate $4 million of the Department's 2012 appropriations to fund research and response. One of the problems facing researchers is the lack of population data on common species such as the
little brown bat. Endangered species like the Indiana brown bat are more closely inventoried, but both species are dying from the disease. Six species of North America's 45 species of bat are affected; all of the affected hibernate in winter. A spokesperson for Bat Conservation International characterized the disease as a potential extinction event on the order of the passenger pigeon or bison. Reports that natural resistance to the virus is increasing among decimated northeastern colonies where the diseases was first detected in the Andirondacks, but that may only be wishful thinking. European bats seem to be immune to the disease, and may offer some clues as to how to combat the deadly infection before it wipes out bats worth $3.7 billion annually in insect control.
