Deadly Bat Fungus Spreads to Iowa

Iowa wildlife officials announced today that the fungus known to cause devastating illness and death in North American bats has been detected for the first time within the state's borders. The bat disease, known as white-nose syndrome, has spread over much of the eastern United States and eastern Canada over the past six years, after first appearing in New York in 2006. Bats in 19 states and four Canadian provinces have contracted the disease; nearly 7 million have died.

"The spread of this pathogen to Iowa is terrible news for our bats and for us," said Mollie Matteson, a bat specialist with the Center for Biological Diversity, which has worked for years to secure funding and cave closures to stop white-nose and this spring petitioned the White House for national action. "It's a disaster for farmers, too, who depend on bats to control crop pests by eating millions of insects."

Biologists swabbed the fungus off a hibernating big brown bat this past winter while studying the epidemic. Lab results confirmed the fungus's presence, but as yet biologists have found no associated sick bats or bat mortality in Iowa. The fungal detection occurred at Maquoketa Caves State Park, in the eastern part of the state.

For the past two years, state officials kept the caves at Maquoketa closed to tours as a precautionary measure to prevent the possible spread of the disease by people. This spring the state decided to reopen the caves to visitors, citing new funding to hire staff that will educate park visitors about the bat disease. Now the park must switch from trying to prevent movement of the bat-killing disease into the caves to trying to prevent it from being carried to new, uninfected sites. To keep fungal material contained, park officials say they will provide a decontamination mat visitors must step on after touring the caves.

Earlier this spring, white-nose syndrome was officially reported in neighboring Missouri. The fungus, though not yet the disease, was first documented there in 2010.

Biologists believe bats transmit the lethal fungus themselves, but that human transport is the primary means for the fungus to make large jumps beyond the dispersal distance of bats. Indeed, human transport likely brought the disease to North America from Europe, where it is common but does not kill bats.

"Opening a tourist cave when white-nose syndrome was documented in a neighboring state was questionable, but keeping a known contaminated cave open to a high volume of tourists is irresponsible," said Matteson. "Iowa state park officials need to reconsider their decision to open Maquoketa, in particular, because Iowa, along with Missouri and Oklahoma, now represents the western front of this catastrophic epidemic."

Researchers are working to develop an effective way to combat the fungus, including possible vaccines or antifungal treatments. However, development of a practical treatment is uncertain and at best likely several years away. Meanwhile, biologists are concerned the disease could spread across the country, threatening the survival of more and more bat species.

Background
White-nose syndrome is caused by the fungus Geomyces destructans. The disease was first documented in a cave in upstate New York in 2006. Seven species of bat have been infected. Another two bat species have been found with the fungus on them, but have not yet suffered mortality. In northeastern states, where the bat disease has been present the longest, bat populations are down by more than 90 percent. Biologists believe several bat species may go extinct as a result.

The white-nose fungus has been found on cave-dwelling bats in Europe but does not appear to cause them any significant health problems. Scientists are suspicious of long-distance leaps of the disease, especially where they have occurred in caves that are popular sites for visitation and recreation, and have expressed grave concern that the disease could spread to hibernating bats throughout North America. In all, as many as two dozen bat species could be at risk.

The loss of bats is a potential economic disaster. Scientists have estimated that insect-eating bats consume enough agricultural pests to be worth $22 billion annually to American farmers.

For more information, visit SaveOurBats.org.