USFWS Proposes Listing of Tricolored Bat

September 13, 2022
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Tricolored bat (Perimyotis subflavus)

Tricolored bat (Perimyotis subflavus)

On September 13, 2022, the U.S. Fish and Wildlife Service announced a proposal to list the tricolored bat (Perimyotis subflavus) as endangered under the Endangered Species Act (ESA). As of the time of this proposed listing, guidance and regulations have not yet changed; however, changes may be expected—as is the case for the northern long-eared bat, which will be ruled on in November.

Based on a thorough review of the species’ status, the species was found to have declined so dramatically across its range that it now meets the definition of endangered under the ESA. White-nose syndrome has caused estimated declines of more than 90% in affected tricolored bat colonies and is currently present across 59% of the species’ range. 

In the United States, the tricolored bat’s range includes Alabama, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Vermont, Virginia, Wisconsin, West Virginia, Wyoming, and the District of Columbia.    

During winter, tricolored bats hibernate in caves, abandoned mines, and abandoned tunnels ranging from small to large in size. In the southern U.S., tricolored bats may hibernate in road-associated culverts. During spring, summer and fall months, they roost primarily among leaf clusters of live or recently dead deciduous hardwood trees. They also roost among Spanish moss in the south and bearded lichen in the north.   

The proposed rule to list the tricolored bat as endangered appears in the September 14, 2022, Federal Register. Public comments on the proposal may be submitted through November 14, 2022. 

Transportation projects covered under various programmatic consultations will not be impacted by the reclassification provided they are completed by the end of the year. Biologists strongly encourage mist-net surveys proposed for the 2022 summer survey season to include radiotelemetry for both species. EnviroScience bat biologists routinely conduct both acoustic and mist-net bat surveys, develop conservation and management plans, and work with clients to create conservation and avoidance measures. Our team is qualified and able to help you navigate your project through the ESA Section 7 Consultation process. We are keeping up with the latest information and are available at 800.940.4025 to answer any questions or concerns as to what this proposed reclassification may mean for your projects.


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