A new fungus is in the frame for ‘White Nose Syndrome’, a nasty condition ravaging America’s bat populations.

Over 100,000 hibernating bats in the north-eastern United States have succumbed to the syndrome, which is characterised by white fungus growing on the nose, ears and wings (see – ‘White Nose Syndrome’ threatens America’s bats – January 31). A new paper from Science characterises this fungus and identifies it as a previously unknown member of the Geomyces group (paper abstract, press release).

While some coverage claims this solves the mystery of the bat deaths it is actually still unclear if this fungus is directly causing the mortality, or if it is merely exploiting animals that have been weakened by some other cause.

“Fungi are opportunistic pathogens they don’t usually attack and kill otherwise healthy animals,” says David Blehert, a US Geological Survey researcher and author of the Science paper (Scientific American).

The Boston Globe notes:

It’s not clear why the bats are dying – the leading hypothesis is that the fungus bothers the bats so much that they wake up to groom themselves during the exact time they need to be conserving energy to make it through the long winter. In Vermont, Massachusetts, New York, and Connecticut, hundreds of skinny bats last winter were found weakly flying in the middle of the day – possibly looking for food.

“The fungus is in some way involved in causing the bats to starve to death,” says Thomas Tomasi of Missouri State University in Springfield (LA Times). “They are burning up too many calories, at a rate faster than they can sustain.”

Map: USGS

Photo: Al Hicks / USGS