Efforts to prevent the spread of a fungus that causes white-nose syndrome in bats will be stepped up after a low level of the fungus was detected on a hibernating big brown bat at Iowa's Maquoketa Caves State Park.
The detection of the fungus came from a swab taken during sampling on the hibernating bats in March. The testing is used to detect DNA that would indicate the presence of the fungus (Geomyces destructans) that causes white-nose syndrome, which has been deadly for bats particularly in the northeastern portions of the United States and Canada.
The testing was done as part of a national study being conducted in an effort to stop the spread of the disease. A total of 15 bats were swabbed at Dancehall Cave with the very low level of the fungus detected on only one bat.
“The level is so low it’s difficult to say what this detection means,” said Daryl Howell of the Iowa Department of Natural Resources. “It may be at a level low enough that it may not infect the bats at all or it could be just the beginning of an outbreak that we will see in the future.”
Howell said even the small detection of the fungus changes the dynamics at Maquoketa Caves State Park. “We now go from trying to prevent the fungus from getting into the cave to trying to prevent it from getting out."
To that end, the DNR will be adding mats with disinfection solution that people will walk across after leaving the caves to decrease the potential of spreading the fungus to other caves and bat populations. People who have recently visited other caves will also walk across the disinfection mats prior to going into Maquoketa Caves.
The DNR also will have staff available at the caves to provide information to visitors on how to prevent the spread of the fungus. After participating in the educational program, cave visitors are provided a wristband. So far this year, more than 10,000 wristbands have been given out.
“Education is probably the most effective tool we have to prevent the spread of the disease,” said Kevin Szcodronski, chief of the state parks bureau.
Maquoketa Caves were closed for two years because of concerns about white-nose syndrome and the approximately 400 bats that hibernate there in the winter. The caves were reopened this spring because the DNR was able to have staff available to educate the public about precautions needed to prevent spreading of the disease.
“We were fortunate in that the Legislature appropriated enough money for us to be able to offer this kind of service to the public. We simply didn’t have the funding the previous two years to be able to do this,” said Szcodronski.
Szcodronski said one of the primary messages to visitors at Maquoketa Caves is to not visit other caves with any clothing or gear that was used there.
Howell said options are being looked at to increase sampling at Maquoketa Caves next winter because healthy bat populations are important both ecologically and economically. Many species of bats feed voraciously on insects resulting in an estimated $3 billion of savings to the U.S. agriculture industry each year by providing pest control, according to a 2011 article in Science Magazine.
White-nose syndrome is known to be transmitted primarily from bat to bat, but fungal spores may be inadvertently carried to caves by humans on clothing and caving gear. The syndrome is not known to pose a threat to humans, pets or livestock.