LONGMONT, Colo. — Two "little brown bats" infected with white-nose syndrome (WNS) were discovered in Boulder County, Colorado Parks and Wildlife said Monday.
WNS is caused by an invasive fungus that has killed millions of bats in North America.
A "little brown bat" was found crawling on a public bike path in Longmont on February 29. It was collected by a wildlife rehabber, who determined the bat was dehydrated and its wings were brittle. The rehabber submitted the bat to the CPW Wildlife Health Lab for further investigation. Testing by Colorado State University confirmed the bat suffered from white-nose syndrome.
Two weeks later, a second "little brown bat" in Boulder was confirmed to have WNS, according to CPW. The agency said this indicates that additional bats have been exposed and may be found in the coming weeks.
The fungus has been confirmed in three "little brown bat" summer roosts in Colorado, but no sick bats have been detected in the state until now, according to CPW. The disease was first discovered in Colorado in March 2023 in a Yuma bat collected by National Park Service staff at Bent's Old Fort near La Junta.
WNS was first documented in New York in 2006. Since then, it has been confirmed in 12 North American bat species and occurs in 40 states and eight Canadian provinces, CPW said.
CPW said the fungus is spread from bat to bat, "making it impossible to stop its spread in the wild."
“While it is unfortunate to discover this deadly disease in a second Colorado bat species, CPW did anticipate that this would happen based on what has been documented in other states,” said Dan Neubaum, CPW Species Conservation Program Manager, in a statement. “We will continue to monitor the spread of this disease with our partners and ask the public to report sick or dead bats to CPW, particularly when found during winter and spring months."
The state agency said WNS's impact could be "devastating" on Colorado. At least 13 of the state's 19 bat species are susceptible to the disease. A large-scale loss of bats could mean trouble for the health of Colorado's ecosystems and economy. CPW said bats, which are "voracious" insect eaters, contribute $3 billion annually to the U.S. agricultural economy through pest control.
The fungus that causes WNS does not infect humans or pets, but it can be transported on gear or clothing that has been in contact with contaminated environments, including caves where bats hibernate.
“We continue to ask those visiting caves to decontaminate their gear to prevent human spread of the fungus and remind the public not to handle bats when encountered but instead report them to CPW, wildlife rehabbers, or the Colorado Department of Public Health and Environment.”
To help slow the spread, CPW is encouraging the community to follow these recommendations:
- Stay out of closed caves and mines.
- Decontaminate footwear and all caving gear before and after visiting or touring caves and other places where bats live.
- Do not touch bats. Report dead or sick ones to CPW by calling 303-291-7771 or email wildlife.batline@state.co.us.
- Gear and clothing used in areas where the fungus or WNS occurs should not be used in areas where the fungus is not known to occur.
- To avoid accidentally transporting bats, check canopies, umbrellas, and other outdoor items for bats that may have roosted in nooks or crannies.
