A fungal disease has killed 6.7 million bats in North America, up from a prior estimate of 1 million, the Center for Biological Diversity said in a report, citing biologists.
Biologists at the Northeast Bat Working Group’s annual meeting last week raised the estimate of deaths caused by white-nose syndrome, a fungal disease that attacks the mammals while they hibernate, the center said in a report. The syndrome now infects bat colonies in 16 U.S. states and four Canadian provinces. The disease was first discovered in 2006 in New York and has spread from Nova Scotia to Tennessee, the center said.
The value of bug-eating bats to the U.S. agriculture industry is about $22.9 billion a year, according to a report in the journal Science last year. Bats’ pest-suppression value to agriculture is about $74 an acre, according to the report published on April 1. As the disease spreads to crop-producing areas, pesticide costs may mount, the Center for Biological Diversity said.
“The loss of so many bug-eating bats has likely had an impact on insect populations, including those that are pests on crops,” the center said. “Since the bat disease has only shown up in the Midwest and South in the last couple of years, the full effects of declining bat numbers on regions more strongly dominated by agriculture than the Northeast may take some time to show up.”
The U.S. government has allotted $4 million for research and management of the disease, according to the report. Researchers have been seeking a cause for the illness since 2006, when it was first noted in a photograph taken by a recreational cave explorer in New York, David Blehert, a researcher at the U.S. Geological Survey in Madison, Wisconsin, said in October.
It’s unclear where the fungus originated. The bats catch the illness through physical contact, and it isn’t spread through the air, scientists have said. If infected bats are removed from hibernation, warmed and given food and water, they can recover from white nose syndrome, Blehert said in October.