Release from Iowa DNR
RAPID SPREADING DISEASE PROMPTS CLOSURE OF CAVES WHERE BATS HIBERNATE
DES MOINES – State natural resources officials are closing state-owned caves that bats use for hibernation to help slow a disease known as white-nose syndrome that is killing bats across the eastern half of the United States and now has surfaced in Missouri. In Iowa, those caves are primarily found in the northeast and far southeast counties.
Daryl Howell, an environmental specialist with the DNR’s land and waters bureau, said the DNR will be closing caves that could likely serve as a bat roost for hibernation, like those found at Maquoketa Caves State Park, Starr’s Cave, near Burlington, and Searryl’s Cave in Jones County starting Monday, May 3rd. Caves closed to the public will be posted with a sign
The closure of caves follows recommendations by the U.S. Fish and Wildlife Service due to the rapid spread of white-nose syndrome into the Midwest. State-owned caves have already been closed in Indiana and Illinois.
“We are reluctant to do this because one of our primary goals is to encourage Iowa citizens to explore the outdoors, but we also recognize that we have a responsibility to protect natural resources,” said DNR Director Richard Leopold.
For privately-owned caves known to have hibernating bat populations, Howell said the DNR is recommending that cave owners close their caves as well.
“We don’t know a lot about this disease or how it is transported, but are taking precautions to help slow the spread,” said Daryl Howell. “The disease is transmitted bat to bat, but it is also likely transported to sites inadvertently by people carrying it in on their clothing or in the mud on their shoes.”
White-nose bat disease was first found in the northeast U.S. in 2006 and has killed an estimated 1 million cave-hibernating bats since. It was confirmed in Missouri, near St. Louis, last week.
Iowa is home to nine bat species and of those only four roost in caves: Big Brown, Little Brown, Long Eared and Eastern Pipistrelle, with Big Brown being the most common. Bats are a major predator of flying insects, a good portion of which are garden and agriculture pests. Plus, they eat mosquitoes. While bats will not control insects completely, they do help to keep the insect population in check.
Hibernation season in Iowa is roughly from October into March and about 2,000 bats will hibernate in Iowa each year.
“We don’t have a large hibernating bat population, like Missouri. In Iowa, we have 35 caves where hibernation occurs – large and small – that host an estimated 2,000 bats, in a given year,” Howell said. “In the spring, our caves can serve as a stopping point for migrating bats.”
How long white-nose syndrome remains a threat in a particular cave has not yet been determined.
“At this point, we have a lot more unknowns than we have knowns. There is a lot of research in progress that will help us to understand where the fungus came from and how long an infected cave will be infected. But we just don’t have a lot of information right now,” Howell said.
“If we can slow the spread of white-nose, it may give us the time needed to answer questions about the best management practices that will save bat populations,” Howell added.