White-Nose Syndrome

White-nose syndrome is devastating bat populations in the Northeastern United States. First discovered in a cave near Albany, New York, in February 2006, white-nose has now spread to nine states (New York, Vermont, New Hampshire, Massachusetts, Connecticut, New Jersey, Pennsylvania, West Virginia, and Virginia) and has killed one million bats. In caves where it appears, it kills 90 to 100 percent of the bats.

White-nose syndrome is caused by the newly discovered and named Geomyces destructans. The fungus covers the non-hairy parts of its bat victims (mainly their noses and wings) with white fungal fibers, giving the affliction its name. However, since scientists have not yet been able to determine that Geomyces destructans is the only pathogen that causes the deaths, white-nose is still a syndrome, rather than a disease.

It may be that the fungus, which thrives in cold temperatures and only strikes bats in the winter when they’re hibernating and their immune systems are shut down, saps the bats’ fat reserves and they actually die of starvation.

The fungus, which has spread to new caves and states each winter since its discovery, spreads through bat-to-bat contact. In hibernacula, when bats sleep clumped together hanging from walls and ceilings of caves, there is plenty of bat-to-bat contact and ample opportunity for the fungus to spread. However, it may also spread on the caving gear of spelunkers and scientists, so some caves have been closed to humans in an effort to prevent white-nose from spreading further.

So far, white-nose has primarily affected the little brown bat (Myotis lucifugus) and the endangered Indiana bat (Myotis sodalist). Scientists and conservationists are concerned about the endangered Virginia big-eared bat (Corynorhinus townsendii virginiaus).

Scientists haven’t found evidence of white-nose syndrome in Virginia big-eared bats yet, but they have found the fungus in the caves where the bats hibernate. Due to the restrictions on entering caves, scientists haven’t been able to positively confirm that the endangered Virginia big-eared bat is already affected by the white-nose syndrome epidemic. G. Destructans has been found in hibernacula occupied by Virginia big-eared bats, though, and scientists think it is likely that if they haven’t already been exposed, they will be soon.

Given the lethality of white-nose syndrome and this species’ already low population levels, the Zoo decided to put a small portion of Virginia big-eared bats into captivity, as a precaution against extinction if white-nose syndrome collapses their populations.