Ohio farmers could suffer more than $740 million a year in agricultural losses, and possibly as much as $1.7 billion, if the new deadly disease called white-nose syndrome wipes out the state's bats, according to a recent study in the journal Science.
Especially hard hit, the study said, would be the rich farming counties in the state's west and northwest, such as Darke, Wood, Mercer and Putnam, where typical losses could range from $18 million to $23 million per county per year.
"Simply put, bats eat a lot of insects -- insects that bother us around our homes, and insects that can damage crops and forests," says Marne Titchenell, Ohio State University Extension wildlife specialist, who was not part of the study, but gives bat conservation workshops around the state and studied southern Ohio bat populations in graduate school.
"It's logical to assume we'll lose a significant amount of the pest-control services that bats provide us as the disease spreads through Ohio and potentially the Midwest," Titchenell says.
The numbers, from an article called "Economic Importance of Bats in Agriculture" in the current issue of Science, are estimates based on crop acreage, the number of crop pests eaten by bats, the damage to crops that their feeding prevents, and the need, as a result, for farmers to spend less on pesticides.
Wildlife officials confirmed the first case of white-nose syndrome in bats in Ohio in late March. It's fatal to at least 90% of the bats in infected caves and sometimes as many as 100%. Human health isn't at risk.
Caused by a newly identified fungus, Geomyces destructans, white-nose syndrome -- so named for the white fuzzy growth it causes on bats' muzzles -- was first detected in New York state in 2006, has spread to at least 16 states and three Canadian provinces in eastern North America, and has killed more than 1 million bats.
Ohio's first case was in Wayne National Forest, in the same part of the state where Titchenell did her graduate research, in the Zaleski and Richland Furnace state forests.
In all, the Science study said Ohio's agricultural losses to white-nose syndrome could range from $120 million in years with a low rate of insect pest survival -- meaning there would be fewer pests to cause problems -- to $740 million at a standard pest survival rate to $1.7 billion at a high rate.
But Titchenell cautions that the figures are only estimates, extrapolated as they were from cotton-dominated farmlands in Texas.
"This is the first study I know of to report (bats' agricultural) values by state and county," she said. "But until there's a similar study that extrapolates corn and soybean figures" -- corn and soybeans being Ohio's top two crops -- "we won't know for sure."
The total value of bats to U.S. agriculture -- and the potential loss from white-nose syndrome -- ranges from a low of $3.7 billion to a high of $53 billion a year, according to the study.