RAVERSE CITY, Mich. (AP) — Federal authorities have announced plans to list the tricolor bat as endangered — the second U.S. bat species recommended for designation this year because a fungal disease is ravaging their populations .
The US Fish and Wildlife Service proposed in March to reclassify the northern bat from threatened to endangered as it reached the brink of extinction. The northern bat and the tricolor bat are among a dozen North American bats with white-nose syndrome, which disrupts their crucial winter hibernation.
“White-nose syndrome is decimating hibernating bat species like the tricolor bat at an unprecedented rate,” said Martha Williams, the agency’s director. “Bats play such an important role in ensuring a healthy ecosystem. The service is deeply committed to continuing our vital research and collaborative efforts with partners to mitigate further impacts and restore tricolored bat populations.
Bats provide an estimated $3 billion boost to the U.S. agricultural economy each year through pest control and crop pollination, according to the government.
White-nose syndrome has caused a 90% decline in tricolor bats since the disease first emerged in the United States in New York in 2006. Among the smallest bats in North America, they are named after the three distinctive shades of their brownish-yellow hair. .
Their historic range includes 39 states east of the Rocky Mountains and four Canadian provinces from the Atlantic Ocean to the Great Lakes, as well as sections of eastern Mexico and Central America.
The disease looks like a white fuzz on the muzzle and wings of bats. This causes them to wake up from hibernation and search for food before spring, resulting in dehydration and starvation.
The disease-causing fungus thrives in the types of cold, damp places ideal for bat hibernation: abandoned mines, caves, and tunnels.
The rest of the year, tricolor bats roost among clusters of tree leaves and slink off at dusk to catch insects such as flies, moths and beetles.
Their steep fall makes the bats more vulnerable to other threats compounded by changes in temperature and precipitation linked to global warming, the Fish and Wildlife Service said. Among them are habitat disturbances and deaths caused by wind turbines.
When adding a species to the endangered or threatened list, authorities often designate “Critical Habitat” areas where they can be protected. But the agency decided against it for the tricolor bat, because habitat loss was not the cause of its collapse. And publicly identifying where they roost could increase the risk of vandalism or other damage.
The decision makes sense because bats disperse so widely, said Allen Kurta, professor of biology and bat expert at Eastern Michigan University. They tend to roost and hibernate alone or with a few others.
“As long as we maintain the forests to provide adequate fodder, they have what they need,” Kurta said. “It’s the disease that really kills them.”
A list would prompt the Fish and Wildlife Service to work with industry, landowners and others on ways to limit damage.
More than 150 government agencies, tribes and nonprofits are studying how to stop white nose syndrome and help bats recover, the service said. They monitor the spread and effects of the disease while testing potential treatments.
A fix doesn’t seem close, said Kurta, who attended a specialist meeting in June. Among many ideas is the use of ultraviolet light and chemicals to kill fungus spores or limit their spread, he said, but these would be difficult to apply in the many sites where the bats roost and hibernate. Scientists are also trying to develop a vaccine.
Most affected bat species only give birth to one or two young per year, meaning recovery will take many years even if the disease is brought under control, Kurta said.
The Fish and Wildlife Service will collect comments on the proposed listing until November 14 and hold a public hearing on October 12. He will make a decision within a year.