BAT CRISIS: WHITE-NOSE SYNDROME

Every night in the summer, bats provide an essential service: they eat bugs by the millions. A single bat can eat thousands of insects in one night. While most people seldom see bats and sometimes fear them, bats are truly the “birds of the night” and play a role as essential to healthy ecosystems as the insect-eating songbirds we see during the day.

But in the eastern United States, something terrible is happening to them.

In the winter of 2006-07, scientists in New York documented a mysterious ailment in bats hibernating in caves and abandoned mines near Albany. The obvious physical manifestation of the illness was a fuzzy white ring around the dying bats’ noses. Biologists thus dubbed the unknown affliction “white-nose syndrome”, also known as WNS.

The white fuzz has been identified as a previously undescribed fungus in the genus Geomyces, and has been aptly named Geomyces destructans for the devastating effect it has on hibernating populations. While the fungus is the most visible symptom of this disease, scientists aren’t sure that it is the primary cause of death. Affected bats appear to be starving: something about the disease causes the fat reserves that bats accumulate before entering hibernation to be depleted long before the winter is over.  Since their insect prey is not available in these cold months, they simply run out of energy and die. 

Before they die, infected individuals exhibit unusual behavior.  Bats have been seen in Vermont and western Massachusetts — in the dead of winter and in broad daylight — outside of the protective warmth of the caves. The bats appear to be looking for food and have been observed trying to drink the snow. Mortality rates as high as 100 percent have been observed in hibernacula affected by white-nose syndrome. What was a localized observation by scientists in upstate New York in 2007 is now recognized as an unprecedented threat to bats, occurring in caves and abandoned mines in nine states: Connecticut, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Vermont, Virginia, and West Virginia. Species known to be affected by white-nose syndrome are little brown bats, big brown bats, northern long-eared bats, eastern pipistrelles (also known as tri-colored bats), eastern small-footed bats, and federally listed endangered Indiana bats. Scientists believe white-nose syndrome is probably  transmitted among individual bats, and also possibly acquired from fungal spores present in the caves or mines where bats hibernate.

The origins of WNS are still unclear.  There is speculation that the fungus was introduced by cavers with infected gear (a genetically similar fungus occurs in Europe) or that environmental toxins and other factors predisposed bats to infection by a pathogen that was already present. More than a million bats have died already, and hundreds of thousands more are likely to perish in the coming winter. Without action, certain populations — and perhaps even certain bat species — may be extirpated from the region forever. 

OUR CAMPAIGN

Because white-nose syndrome is a contagion transmittable from one cave to another by bats — and possibly by people, as well — the spread of this disease is rapid and, if it continues, could be devastating to bats already endangered by other factors.

For example, there are fewer than 10,000 endangered Virginia big-eared bats remaining. Further losses to this population are unsustainable. White-nose syndrome could spell the end for the Virginia big-eared bat if the species proves susceptible to it and the disease strikes one or more of its hibernating caves.