The operation of wind energy facilities can potentially harm bats, but the true extent of this danger is not fully understood. In some US regions, a significant challenge to developing wind energy is finding ways to lower the number of bats that collide with wind turbines while maintaining high power production levels. When developing or operating wind energy projects, it’s essential to know the current listing status of bat species to minimize potential permitting delays and understand the potential mitigation required to reduce impacts to bat species. Read on for the listing status of the northern long-eared bat, the little brown bat, and the tricolored bat and how their status may impact your project’s permitting.
Northern Long-Eared Bat Uplisted to Endangered
In January 2023, Northern long-eared bats (Myotis septentrionalis, NLEB) were uplisted from threatened to endangered under the federal Endangered Species Act (ESA). This uplisting negates the existing 4D rules and will require sites that may have an impact on NLEBs to prepare a habitat conservation plan (HCP) in coordination with the USFWS. Implementation of an HCP may increase pre- and post-construction monitoring and mitigation costs compared to previous requirements under the 4D rules, which focused mostly on turbine curtailment strategies. The northern long-eared bat range includes 38 states, with the greatest abundance across the eastern and north-central United States.
Tricolored Bat Listing Anticipated by October 2023
The tricolored bat (Perimyotis subflavus) is a small insectivorous bat distinguished by its unique tricolored fur and often appears yellowish to nearly orange. Tricolored bats face extinction due primarily to the wide-ranging impacts of white-nose syndrome, a deadly disease affecting cave-dwelling bats across North America. It is estimated that white-nose syndrome has caused more than 90% declines in affected tricolored bat colonies across most of the species’ range. This has made the species a candidate for being listed as Endangered under the federal Endangered Species Act (87 FR 56381). The proposal to list was published in September 2022 and formal listing is expected in the third quarter of 2023.
The once common species is wide-ranging across the eastern and central United States and portions of southern Canada, Mexico, and Central America. In winter, tricolored bats are often found in caves and abandoned mines. However, in the southern United States, where caves are sparse, tricolored bats are often found roosting in road-associated culverts where they exhibit shorter torpor bouts and forage during warm nights. During the spring, summer, and fall, tricolored bats are found in forested habitats where they roost in trees, primarily among leaves of live or recently dead deciduous hardwood trees, but may also be found in Spanish moss, pine trees, and occasionally human structures. Due to their extensive range, wind energy projects in 39 states would be impacted by their listing as an endangered species. Listing would require projects to prepare an HCP to obtain incidental take coverage, likely increasing post-construction monitoring and mitigation costs.
Little Brown Bat Listing Expected in 2023
The little brown bat (Myotis lucifugus) will likely be listed with critical habitat designated by the end of 2023. The listing of little brown bats would likely be more impactful than tricolored bats since little brown bats are encountered more frequently, with a range encompassing the entire continental United States including Alaska. Listing would trigger requirements to prepare HCPs to obtain incidental take coverage, likely increasing post-construction monitoring and mitigation costs.
How will these bat listings affect wind energy projects?
Due to the high risk of take, wind projects will be required to prepare an HCP in coordination with the US Fish and Wildlife Service (USFWS) for new and existing sites to mitigate the risk of enforcement or permanent curtailment of turbines. Mitigation may be costly due to the frequency and quantity of these bats found on site during operations.
Conservation strategies for this species and other cave roosting bats are also challenging, as there is no agreed-upon solution to white-nose syndrome, which is the primary threat to the species. Federal and state agencies will likely need to work together to develop one or more in-lieu fee programs to support research activities that enhance understanding of white-nose syndrome and seek potential solutions.
How can Dudek help navigate regulatory requirements for listed species?
Dudek’s permitting specialists have experience preparing and implementing habitat conservation plans (HCP) for individual sites and large regions incorporating multiple operational facilities. Our permitting specialists are involved with some of the largest HCPs in the country and have a proven track record of acquiring permits. We can assist in planning to determine if these potential listings may affect your project, survey/study design, and/or mitigation requirements.
Contact us for more information on how these bat listings may impact your project and for support navigating a path forward.