– Endangered grassland birds thriving at landfill, according to County-led study –

Endangered grassland bird species, such as the Eastern meadowlark and grasshopper sparrow, have found refuge in Fairfax County thanks to a 50-acre swath of meadowland atop the I-95 Landfill Complex in Lorton and some modified land management procedures there. Recent efforts by the Department of Public Works and Environmental Services (DPWES) are helping the birds survive and thrive at the landfill.

County-Led Study Prompts Changes to Mowing Procedures

Based on a three-month County-led study last fall, which scientifically documented the species and quantities of birds, mowing operations have been adjusted at the landfill, which will give nesting birds a better chance to survive, as some nests may be in the direct path of mowers.

Initially, local bird advocates raised concerns about protecting the grassland birds that nest at the I-95 Landfill – rare sightings in Fairfax County given the scarcity of wide-open meadows in the region – which piqued the interest of the Board of Supervisors, who asked that a study at the landfill be conducted.  See Board meeting summary, page 23.

“Local birdwatchers have long-known that the I-95 landfill is about the only place you’ll see an Eastern meadowlark in Fairfax County,” said Blair Evancho, a DPWES grassland habitat intern who led the 2024 study. Evancho went on to say, “Grassland birds build nests, lay eggs and raise their hatchlings on the ground in their peak nesting season of May through July.”

“The modified mowing procedures – which include restricted mowing during peak nesting season and raising mower blades to eight-inches height – should give grassland birds a better chance to thrive,” Evancho said.

DPWES-Led Study

Thirty-nine bird species were documented at the I-95 landfill during the study period. Of those, 29 species were documented within 10 specific study zones, including three of regional concern: the Eastern meadowlark, the bobolink and the grasshopper sparrow.

The abundance of American kestrels, a small grassland falcon, was also noteworthy.

Evancho was hired by DPWES to conduct the study. Between August and October 2024, Evancho and DPWES colleague Carlos Leiva visited the observation sites at sunrise, when birds are most active.

“Two observers at each site provided a 360-degree view,” Evancho said.

Evancho and Leiva documented the bird species they saw and heard. They also noted environmental conditions such as temperature and windspeed at each spot.

See DPWES’s I-95 Landfill bird report here.

Among all bird species, grassland birds are facing the steepest population decline nationally, primarily due to habitat loss from urban development that’s taking away the open meadowlands where they live.

DPWES will continue studying the I-95 Landfill birds to document longer-term trends.

About the I-95 Landfill

The closed-and-capped portion of the landfill at the I-95 Complex, which has not accepted municipal waste since 1995, features acres of un-mowed grass at the top of a large hill that supports an ecosystem attractive and suitable for grassland bird species. The wide-open, grassy meadowland, bushes and other vegetation, as well as food and water sources, support a significant diversity of bird species.

While mowing the grounds is part of landfill maintenance procedures required by state and federal law to provide access to the landfill’s methane gas wells and enhance safety for landfill workers, the modifications will give wildlife a better chance to survive.

“Fairfax County has long been a leader in environmental sustainability,” said Eric Forbes, DPWES deputy director who oversees the Solid Waste Management Program. “Continued study of grassland birds at the I-95 landfill, in partnership with local and national bird advocacy organizations, will not only contribute to bird conservation science, but also position Fairfax County as a national leader in sustainable landfill management practices.”

Additional Resources

Podcast: Fairfax County EnviroPod Episode 52 features bird study Lead Blair Evancho

Video: DPWES YouTube video of a bird survey and mowing at I-95 Landfill Complex

Web:

• Fairfax County’s Solid Waste Management Program’s I-95 Landfill Complex web page
• Fairfax County Park Authority Birdwatching web page*

*To ensure safety of staff, visitors and wildlife, public access to the I-95 Landfill is restricted.