Saving the Nation's Bats

Scientists find cures for a deadly fungus that is attacking wild bats

Sep 13, 2010 | By Brenda Iasevoli

Scientists at New York's Department of Health, in Albany, helped identify a fungus that has killed more than 1 million bats in the U.S. since 2006. Recently, they found several drugs that may fight the disease.

One of the drugs that proved successful against the fungus is a widely used antifungal medicine for humans called fluconazole (flu-con-uh-zole). Five antiseptics, substances that stop the growth of germs, also proved successful in stopping the fungus. The antiseptics may be used to decontaminate the shoes and hands of people who visit bat caves in an attempt to stop the fungus from spreading.

Al Hicks, a top bat expert at the Department of Health, cautions that there is still a lot of work to be done. "We know the drugs kill the fungus in a petri dish in our lab," Hicks told TFK. "That was the first step. The next step is to test the drugs on bats to see if the drugs can kill the fungus without harming the animals."

What is Killing Bats?

The disease is called white-nose syndrome. A white fungus grows on a bat's nose, wings and ears. Scientists have found that bats killed by the fungus have severely depleted fat stores. It is believed that when hibernating bats wake up to remove the irritating fungus, they burn fat that they need to survive the winter. The bats end up dying of starvation.

Vishnu Chaturvedi, a microbiologist and a lead researcher for the Department of Health, told TFK that the depleted fat stores are a big clue in the fungus mystery, but that more research needs to be done in order to say exactly why the bats are dying from the fungus.

"It might not be as simple as they're waking up too much," he says.

Another theory is that the fungus damages wings, which are important for maintaining a bat's water balance and blood pressure.

What is certain is that the fungus—which was first discovered in Albany, New York's capital, in 2006—may wipe out bat populations if it isn't stopped. Researchers at New York's Health Department found that in three years the fungus had reduced a colony of about 185,000 brown bats to 2,000. Today the disease can be found in bat populations as far south as Tennessee and as far west as Oklahoma.

A Future for Bats?

Bats eat mosquitoes and other insects that harm crops and carry disease. They are also important pollinators in desert and tropical habitats. But saving these beneficial animals will be difficult because female bats only give birth to one pup per year.

Another challenge for scientists is to find a safe way to treat the fungus. Treatments are not always safe. For example, drugs used a few years ago to help frogs attacked by a fungal disease ended up harming tadpoles. Moreover, antiseptics could harm bat habitats that support plant and animal life. A national action plan to begin combating the fungus in bats is due out in a few weeks.

"The challenges are great," Hicks told TFK. "But we must protect bats for future generations, so that our children and grandchildren can experience this amazing animal."