Tricolored bat on brink of extinction due to fatal fungus

The U.S. Fish and Wildlife Service (FWS) announced a proposal on Tuesday to place tricolored bats on its endangered species list as the animals struggle to contend with a deadly fungus in their dark and damp abodes.

The species is on the brink of extinction due primarily to the impacts of “white-nose syndrome,” a disease caused by the growth of a fungus that looks like white fuzz on the bats’ muzzles and wings, according to the FWS.

The fungus thrives in cold, dark, damp caverns and typically targets bats during hibernation. Those animals infected wake up more frequently, often succumbing to dehydration and starvation before spring comes, the FWS explained.

“White-nose syndrome is decimating hibernating bat species like the tricolored bat at unprecedented rates,” FWS Director Martha Williams said in a statement.

“Bats play such an important role in ensuring a healthy ecosystem, Williams continued. “The Service is deeply committed to continuing our vital research and collaborative efforts with partners to mitigate further impacts and recover tricolored bat populations.”

Bats contribute at least $3 billion each year to the U.S. agricultural economy by means of pest control and pollination, according to the FWS.

Tricolored bats are found east of the Rocky Mountains in 39 U.S. states and the District of Columbia, in four Canadian provinces from the Atlantic Coast to the Great Lakes, and in parts of eastern Mexico, Guatemala, Honduras, Belize and Nicaragua, FWS said.

The proposal to classify tricolored bats as endangered arose following a comprehensive review tracking the decline of the species, according to the FWS.

The review indicated that population numbers have plunged so dramatically across the range of the species that it now meets the definition of endangered under the Endangered Species Act.

While white-nose syndrome is the most serious danger to the tricolored bat, other threats are gaining traction as climate change exacerbates a wide range of variables, the FWS stated.

Such variables include changes in temperature and precipitation, mortality at wind energy facilities and disturbances in roosting, foraging, commuting and wintering.

The FWS said that it has plans in place to work with stakeholders to conserve bats while allowing economic activities within their range to continue to occur.

For example, habitat conservation plans could help wind projects advance after properly minimizing and mitigating impacts to bats, the FWS explained.

Tuesday’s proposal follows a March 2022 announcement of a similar finding related to northern long-eared bats, which the FWS recommended to be reclassified from threatened to endangered.

When a species is listed under the Endangered Species Act, the FWS works with industry and other partners to pinpoint strategies that can help reduce the harm, harassment and killing of the animals, while deploying a wealth of conservation tools.

The ongoing crisis affecting tricolored bats is a testament to the importance of the Endangered Species Act and efforts to protect species before population declines become irreversible, a statement from tge FWS said.

In July, the FWS announced the repeal of the last remaining Trump-era shifts to the Endangered Species Act, as The Hill reported.

Former President Trump’s changes had required the FWS to accept private landowners’ claims that making an area a protected habitat would bring economic harm. By restoring the pre-Trump status quo, such exclusions are now again at the discretion of the secretary of the Interior Department. 

The July declaration came weeks after a federal judge vacated another related Trump rule, which had said that equal protections did not apply to those species classified as endangered and those considered threatened.

Prior to that announcement, another Trump-era rule was revoked that had imposed stricter constraints on which areas qualified as critical habitats.

As far as tricolored bats are concerned, however, the FWS determined that designating critical habitats would not be advisable because current or threatened modifications of the bats’ habitat are not bringing range-wide improvements to the species.

In addition, the FWS warned that identifying the locations of bat roosts could increase direct harm to the animals or vandalism of their habitats.

Members of the public can comment on the proposed rule through November 14, by searching for docket number FWS-R5-ES-2021-0163 on the federal rulemaking portal.