White Nose and Climate Change Threaten Bats



     WASHINGTON (CN) – In separate actions, the U.S. Fish and Wildlife Service finalized the endangered listing status for the Florida bonneted bat, and proposed endangered listing status for the northern long-eared bat, under the Endangered Species Act.
     The listing and proposal were hastened by a 2011 settlement agreement between the USFWS and the Center for Biological Diversity (CBD), one of the agency’s most frequent litigators. The settlement resulted in a court-approved five-year workplan to speed listing decisions for hundreds of species across the country.
     The 6.5 inch long Florida bonneted bat, named for its two broad ears which project over the eyes from the center of the head, is a “fast-hawking” bat that uses echolocation to hunt insects in open spaces. Its unique call can be heard, since its echolocation is not in the inaudible range for humans like most other bats. Surveys of the bats are aided by the fact that their calls can be heard and recorded.
     The bonneted bat lives in colonies, with one male defending its harem of females from competing males. The bats are slow to reproduce and have low fertility. They have a restricted range with only 11 known colonies.
     The bats prefer tree cavities for roosting, and may face competition for those roosts from other animals. Other habitat challenges derive from human population growth, development and agriculture, including pesticide use, which both kill the bats’ main prey, and affects the bats themselves.
     Climate change is projected to have severe effects on the bats in the future, the action said.
     “[T]he bats’ habitat is projected to experience sea-level rise of as much as three to six feet within this century, meaning that nine of the 11 roost site locations will be either fully or partially inundated. With even one foot of sea-level rise, four roost sites would be largely or completed inundated,” the CBD said in its press release.
     Like in the in the proposed action for the bonneted bat, in the final action, the USFWS found that critical habitat is not determinable due to insufficient information, listing noted that the USFWS needed more information on the bats’ needs and habitat preferences to enable a critical habitat designation.
     The northern long-eared bat is half the size of the bonneted bat, and unlike the Florida bat, it hibernates during the winter. The long-eared bat also roosts in trees, though the colonies are large in comparison with the bonneted bat. Despite its extensive range and larger colonies, the northern long-eared is suffering “unprecedented mortality” from white-nose syndrome (WNS).
     The fungal disease was first documented in New York in 2006 and it has spread rapidly through the bats’ range in the Northeast and Midwest. “Service biologists and partners estimate that at least 5.7 million to 6.7 million bats of several species have now died from WNS,” the action noted. It is thought that poor immune function during hibernation compromises the bats’ ability to fight the infection.
     The severity of the threat of WNS to the northern long-earred bat is so great that the agency has found no other threats that are as severe or immediate. There is no known cure for WNS, the agency said.
     “Endangered species status for the northern long-eared bat is not an automatic cure, but it does represent admission to the ICU,” Mollie Matteson, a bat specialist with the CBD was quoted as saying in the group’s press release.
     The USFWS service noted that it does not have sufficient information to make a critical habitat designation for the northern long-eared bat, but plans to do so within one year.
     The listing for the Florida bonneted bat is effective Nov. 1.
     Comments on the northern long-eared bat’s proposed listing are due Dec. 2.

%d bloggers like this: