Fort Drum research project findings help biologists understand bat disease
July 21, 2011
FORT DRUM, N.Y. -- As the sun sets over the tree tops surrounding Fort Drum's LeRay Mansion, Fish and Wildlife biologists wait in anticipation for the first sighting of their favorite nocturnal winged critter, a species that is slowing losing presence in North America.
Like drops of rain, bats begin to fall from a wooden box, perched on a pole that has housed more than 150 bats for the past year.
Half a dozen biologists, armed with rubber gloves and brown paper lunch bags, scramble inside a mesh tent that drapes from the top of the box to the ground. The biologists quickly untangle the creatures " who are only about the size of their hands " from the tent's walls and stow them in the bags.
The bagged bats are taken to a gazebo, only yards away, where information such as sex, age, whether or not the adult females gave birth and any potential evidence of white-nose syndrome damage is recorded. A band that has a number corresponding to the recorded information is placed on each bat's leg " right if it's a male and left if it's a female " and they are released, fluttering off into the night sky.
On July 12, Fish and Wildlife biologists from on and off post took part in a research project that involved looking at little brown bats and the effects of white-nose syndrome.
According to the U.S. Fish and Wildlife Service's web site, in 2006, bats hibernating about 40 miles west of Albany were found with an unusual white substance on their muzzles. Of the 41 bat species in the U.S., 25 of them hibernate.
White-nose syndrome is named for the white fungus that appears on the muzzle and other body parts of the bats. The disease has killed more than one million bats in the Northeast and Canada.
The syndrome spreads because thousands of bats live close and cluster together in caves and mines during the winter.
"That's a great place and time for fungus to spread. The fungus does really well in the same (winter) conditions that the bats (thrive in), so it's the perfect situation for this fungus," said Robyn Niber, U.S. Fish and Wildlife endangered species biologist, who took part in the project on Fort Drum.
"Fort Drum is an overall great environment that supports the bats," said Chris Dobony, Fort Drum Fish and Wildlife biologist and project lead.
In 2007, Fort Drum Fish and Wildlife specialists began tracking the bats with radio transmitters to find their roost trees, so they could protect their habitats. Since then, the biologists have identified more than 300 sites across Fort Drum, which helps them get an idea of the distribution of bats on post.
Since 2008, Fort Drum Fish and Wildlife biologists have noticed a drastic decline in all of the myotis " or mouse-eared " bats on post, which include the little brown, Indiana and Northern long-eared bats, Dobony explained. He noted that after white-nose syndrome hit Fort Drum's bat population, they found fewer bats were using the roosts discovered on post.
The bats on post were first banded and monitored in 2009, and last year, biologists monitored them on three separate occasions during May, June and July.
Because there is no cure for the disease, many staff members from the U.S. Fish and Wildlife Service focus their time on white-nose syndrome, Niber explained. More than 100 national agencies " including the U.S. Geological Survey, U.S. Forest Service and Department of Defense " and state agencies " such as New York State Department of Environmental Conservation " work together to find ways to slow down the spread of white-nose or come up with a possible cure. As the disease spreads to different states, new federal and state agencies become involved in the project.
The disease has spread from New York down the Appalachians and further west across the U.S., and more sites are discovered each winter, according to the U.S. Fish and Wildlife Service.
"Unfortunately, the fungus is spreading faster than we can learn from it. We're hoping, through the years, that we (find) bats that are resistant and are survivors," explained Noelle Rayman, U.S. Fish and Wildlife endangered species biologist who also assisted with the project.
"People don't understand that there's a lot we can learn from bats," Rayman said, noting that white-nose syndrome has forced biologists to look at bats more closely.
Of the estimated 150 bats in the box on Fort Drum, biologists were able to capture 66 " 40 of those were juvenile bats born this year and 26 were adult females that had all given birth this year.
Dobony said some of the bats escaped capture, and some didn’t even come out of the box. He attributed this behavior to the bats learning from previous years that they can avoid disturbance and capture by staying in the box until the biologists leave.
"The information that we are collecting here provides us a small amount of encouragement in an otherwise depressing situation. Even though our bat house population has declined by about 90 percent of what it historically was, the numbers seemed to have stabilized in the last couple of years, and we have documented that not all the bats are dying," Dobony said.
He added that some bats have survived multiple years, and they are able to recognize this because of the bands. Some bats can heal from damage associated with white-nose syndrome and some are strong enough to produce young, even after being exposed to the disease.
Through this research, the biologists recognize the bats' role as being beneficial to the environment, because they are the primary nighttime predator of insects, Dobony explained.
"There's been recent research that has shows millions of dollars that is saved (because of the) bat's ability to reduce agricultural pests, so farmers don't have to put pesticides on crops (and) we can have more naturally-produced crops," he said.
Biologists are unsure of how large of a ripple effect would occur with the loss of the bat population.
"We don't know what would happen to the ecosystem with the loss of the bat. We've never witnessed widespread losses of animals like this in our lifetime, so we really don't know what the impact (would) be," Niber said.
Bats may provide an important role as prey and predators, but for some, they get a nostalgic feeling by watching bats dart through the summer sky, year after year.
"I just think of a whole generation of children not seeing bats flying in the night sky," said Niber, who grew up watching bats at her grandparents' house each summer.
"We're thinking of the loss of an entire family. It's amazing to think about this entire group of creatures not being in our night skies anymore.”