Bats reintroduced into Vermont caves hit by fungus

AP
POSTED: October 28, 2009

ALBANY, New York (AP) — Wildlife biologists studying a mysterious fungus killing off hundreds of thousands of bats around America want to find out if they can repopulate caves decimated by the disease.

Researchers will introduce 79 healthy little brown bats to two hibernation sites in Vermont hit hard by the fungus, which may have killed as many as 500,000 bats in the eastern United States over several winters.

Scientists suspect a fungus that thrives in cold, moist caves causes white-nose syndrome, named for the sugary smudges of fungus on the noses and wings of hibernating bats.

The repopulation experiment starting Tuesday at caves in Bridgewater and Stockbridge, Vermont, is not aimed at curing the disease. But it could show whether affected caves can sustain new populations of hibernating bats.

"Can you have bats successfully survive there? Or will they develop the disease even if there aren't any infected bats there?" asked Al Hicks, a wildlife biologist for New York's Department of Environmental Conservation.

Hicks said that if the bats shipped in from Wisconsin survive the winter, that could provide evidence that bats can be successfully reintroduced to caves that housed infected animals. It also could show whether the disease persists at hibernation sites even after infected bats are gone.

Entrances at the two sites are screened to keep in the bats. Gates will keep out people.

First noted in upstate New York in 2006, the disease has spread around the U.S. Northeast and has been detected as far south as Virginia. Researchers worry about a mass die-off of bats, which help control the populations of insects that can damage wheat, apples and dozens of other crops.

The repopulation project is a cooperative effort among conservation officials from Vermont, New York and the federal government.

Little Brown Bats in Stedman

Myotis lucifugus has brownish-black fur that has a glossy sheen to it and a belly that is grey-brown. The bat’s feet are mainly for clinging while it roosts. The wings of a bat are superbly constructed and include four fingers and a thumb. At the end of the thumb is a hooked claw, which serves to help the bat climb and crawl along surfaces.

Little brown bats are insectivores, eating moths, wasps, beetles, gnats, mosquitoes, midges and mayflies, among others. Since many of their preferred meals are insects with an aquatic life stage, such as mosquitoes, they prefer to roost near water. They echolocate to find their prey. Often they will catch larger prey with a wingtip, transfer it to a cup formed by their tail, then eat it - smaller prey are usually just caught in the mouth. They often use the same routes over and over again every night, flying 3-6 meters high above water or among trees. An adult can sometimes fill its stomach in 15 minutes; young have more difficulty. If they do not catch any food, they will enter a torpor similar to hibernation that day, awakening at night to hunt again.