As we transition into warmer weather across Virginia and Maryland, bats in the area are emerging from their winter roosts as they transition to migration and breeding seasons.  If your projects involve tree clearing, you may need to follow time of year restrictions for those bat species recognized as threatened or endangered under the Endangered Species Act.

Both Virginia and Maryland are home to varied species of bats, but tree clearing time of year restrictions differ depending on the status of the species.  While many bat time of year restrictions begin June 1, the time of year restrictions for the federally endangered Indiana bat (Myotis sodalis) and the federally endangered northern long-eared bat (Myotis septentrionalis) begin April 1.

Our April 12, 2023 Regulatory Updates webinar addressed bat protections. Learn more here!

Indiana Bat

As a federally endangered species, the Indiana bat is afforded greater protection than other federally threatened or even state endangered species – so tree clearing near known hibernaculum or roosts is restricted for a longer period. If your project is within a county where the Indiana bat is known to hibernate or roost (see map), you must coordinate with the U.S. Fish and Wildlife Service (USFWS) prior to clearing trees during any time of year.

Northern Long-Eared Bat TOYR

Both Virginia and Maryland are home to the northern long-eared bat, a federally endangered species under the Endangered Species Act.

For all projects, the newly released USFWS NLEB Rangewide Decision Key (DKey) should be completed to determine if the project will have an effect on the species. Projects with a May Affect, Likely to Adversely Affect determination will need to adhere to a time of year restriction (no tree clearing) of April 1 through November 14¹ or pursue further coordination with USFWS or U.S. Army Corps of Engineers (COE) as applicable. For projects where a COE wetland permit was issued prior to the NLEB uplisting on March 31, 2023, and tree clearing is not yet complete, the project will need to be re-coordinated through the COE. Projects that do not require a federal permit should also complete the DKey to determine potential effects from tree clearing. Please contact WSSI to assist in this re-coordination process.

Little Brown Bat and Tri-Colored Bat TOYR

Both the little brown bat (Myotis lucifugus) and tri-colored bat (Perimyotis subflavus) are state-endangered in Virginia.  The tri-colored bat has been recently proposed as endangered on the federal level by USFWS, and changes to time of year restrictions are expected in the near future.

  • The Virginia DWR website identifies the approximate location of known hibernacula and known maternity roost trees for the little brown bat and tri-colored bat.
  • Neither species is state-endangered or subject to time of year restrictions in Maryland, at this time.

¹ Projects in the coastal plain of Virginia, east of Interstate 95 and south of the James River, where northern long-eared bats are active year-round have a TOYR from December 15 – February 15 and April 15 – July 30.

Need Help? Just light the Bat Signal!

Wetland Studies and Solutions can help you determine if your project is in an area where threatened or endangered bats are known to hibernate or roost, coordinate with Virginia and Maryland agencies, help plan your future projects around bat time of year restrictions, or develop a Conservation Plan – we can also perform a bat survey on your project site if required. For more information about any of our bat services, reach out to one of our contacts below.


  • Ben Rosner

    Director - Environmental Science

    Gainesville, VA

  • Mike Klebasko

    Manager - Maryland Environmental Science

    Millersville, MD

  • Christie Blevins

    Director - Regulatory

    Gainesville, VA