Hoping to combat a disease that has decimated bat populations in the Eastern U.S., the state Natural Resource Board will consider steps this week to protect Wisconsin’s bats from white-nose syndrome before it reaches the state’s borders.
"We have a rare opportunity to meet an extinction threat head on and deal with it," said Department of Natural Resources Secretary Matt Frank of the measures that will be considered by the board at its meeting Wednesday. "The DNR is taking action now to slow the spread of the disease and conserve as many bats as possible, knowing a (white-nose syndrome) infection is likely."
The disease, a fungus, is named for the white fuzz that covers the fur of infected bats. It has spread through 14 states after being discovered in New York three years ago and has killed 90 to 100 percent of the bats in caves where the bats hibernate. It has moved steadily west and is now in Missouri as well as Ontario. The closest outbreaks are about 300 miles from the state’s borders, close to the 280-mile flying range of bats.
Proposals that would make cave bats a threatened species in Wisconsin as well as make the fungus a prohibited invasive species will be considered by the board Wednesday. Bats are currently not protected in Wisconsin.
While the disease does not infect humans, the threat to bats is of great concern to wildlife experts because of the important role bats play in controlling insects. Frank said bats are critical to farming and forestry because they consume so many agricultural pests — a single little brown bat eats up to 1,000 insects an hour. Bats also help control mosquito populations, important for keeping mosquito-borne diseases, such as West Nile Virus, from spreading.
"Bats, because they are voracious insect eaters, hold an important place in our ecosystem," Frank said.
Wisconsin, with its many caves and old mines, has the largest concentration of bats in the upper Midwest. Dave Redell, a bat ecologist with the DNR, has been traveling the state with other agency wildlife experts to survey the state’s bat populations and working with the owners of caves and mines to protect them from introduction of the disease, which is often spread on boots and clothing by cavers.
Redell has indicated he would be surprised if the disease does not turn up in Wisconsin this winter. All four of Wisconsin’s cave bat species — little brown, northern long-eared, eastern pipistrelle and big brown bats — are susceptible to the disease.
Designating the cave bats as threatened species ahead of the disease would heighten efforts to protect them, according to DNR officials. While the threatened status would allow for greater protection, the plan also calls for creating an incidental take permit that would allow bats to be killed in the event of public health concerns or in the case of building or bridge demolitions and wind energy development projects. The permits would also outline specific precautions that need to be taken to minimize impacts on bats.
By designating the fungus as a prohibited invasive species, steps can be taken to control its introduction on clothing or equipment, according to DNR officials.