Bats are dying by the thousands–including the endangered Indiana Bat but several other species as well–and we don’t know why. The emerging animal disease (human risk remains to be determined) called by its most conspicuous outward symptom: White Nose Disease.
It seems unlikely the white powder on the muzzles is anything more than an ordinary opportunistic fungus (identified as Fusarium by Wikipedia, a common plant pathogen) and a sign the sickened bats are so weak that they cannot groom as normal.
What kills them is a metabolic derangement such that they use up fat reserves usually adequate for hibernation. They starve to death while hanging upside-down asleep. Future investigation may involve use of thermal cameras in suspected caves, since diseased bats will glow hotter than normal as they burn away fat stores that should have carried them through the winter.
Global warming doesn’t seem implicated. Caves involved so far are in New York and Vermont, and not farther south (so far as we know now.) But is it a bacteria? A new virus? And how is it transmitted?
This Boston.com source holds that it is almost exclusively caves visited by cavers where the disease has been found.And of course a caver one day in Argentina could the next day be wearing the same boots in a cave in Vermont. But beyond that, it must be transmissable bat to bat as they congregate as thick as 300 per square foot in some caves. And what happens in the spring when the survivors leave their caves to migrate to other caves hundreds of miles away? We’re about to find out.
Good riddance, you say? Think again. Combined with the loss of bees from Colony Collapse Disorder, this new plague among voracious insect eating bats could have additional, far reaching consequences on agriculture, public health and our increasingly precarious ecological equilibrium.