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. Our graphic below shows the timeframes when tree clearing is allowed in accordance with current species-specific guidance, however regulatory agencies may alter these typical time of year restrictions on a case-by-case basis. WSSI science and regulatory staff can provide support with agency coordination and acoustic bat surveys to aid in site-specific determinations. Click here to read about how northern long-eared bat and tricolored bat consultation guidance is changing.

Indiana Bat

If your project is within a county where the Indiana bat is known to hibernate or roost as indicated in the USFWS IPaC database and there is suitable habitat, 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 Tricolored Bat TOYR

Both the little brown bat (Myotis lucifugus) and tricolored bat (Perimyotis subflavus) are state-endangered in Virginia.  The tricolored 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 tricolored bat.
  • Neither species is state-endangered or subject to time of year restrictions in Maryland, at this time.

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.


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.


  • Ben Rosner, PWS, PWD, CE, VSWD

    Director - Environmental Science

    Gainesville, VA

  • Mike Klebasko, PWS, QPF

    Manager - Maryland Environmental Science

    Millersville, MD

  • Christie Blevins, PWS, CESSWI, LEED AP

    Director - Regulatory

    Gainesville, VA

  • Bob Kerr, PWD, VSWD, SPWS

    Director - Hampton Roads Division

    Virginia Beach, VA