In 2006 a previously unknown disease was discovered killing bats in northern New York State. Since then the disease, now called white-nose syndrome for the symptom it causes in infected bats, has spread to colonies in sixteen states and four Canadian provinces, killing as many as 6.7 million bats in the process. This huge die-off threatens several species of bats with extinction if the disease continues unchecked, and so far research into the problem has produced more questions than answers.
The new mortality figures were released recently at the Northeast Bat Working Group's annual meeting held in Pennsylvania, one of the states whose bat population has been hard hit by the epidemic. Although a few bats were found in Vermont last summer that were confirmed survivors of the disease, raising hopes for a resurgent population resistant to the disease, severely decimated populations are very vulnerable to other pressures such as habitat loss and environmental contaminants.
So far white-nose syndrome hasn't made big inroads into the bat populations in the Midwest and South, areas with some of the largest bat populations in the country. This is one of the reasons scientists are working hard to understand the disease so they can come up with a way to stop its spread. Congress has recently allocated $4 million in the effort to control this disease.
Bats feed on an enormous number of insects, and their decline could have a big impact on pest populations affecting both agriculture and home gardening. Some estimates are that the number of pest insects eaten by bats save farmers from having to spend between $3.7 billion and $53 million annually on pesticides -- a whopping figure that doesn't take into account the benefit to the environment as a whole from reduced pesticide usage.