Wednesday, September 11, 2024
As multi-ton garbage trucks roll in and out 24 hours a day to unload the never-ending detritus of modern life and mammoth forklifts rumble over the I-95 landfill at Lorton, just over the hill, a very different kind of life abounds.
Amid the crickets’ constant chirping, keen listeners may hear the tinkling call of a bobolink. Their fall call is “a repeated ink,” says the National Geographic Field Guide to the Birds of North America. Bobolinks are seven-inch-long birds that live and forage in tall grasses and winter in South America.
Bobolinks migrate through Northern Virginia in the spring and fall and are “very rare in the eastern United States,” says Greg Butcher, retired U.S. Forest Service wildlife biologist. Why are these birds at the landfill? Bobolinks prefer grasslands, a rare and diminishing habitat. Grassland acreage in Virginia may be less than .0001 percent what it was pre-colonization, according to Justin Folks, Natural Resources Conservation Service. “The eastern United States has lost 99 percent of its grassland since European settlement,” notes Butcher.
No Mow
This year, managers designated 50 acres of the 500-acre landfill as a “no-mow” zone, as directed in February by the Board of Supervisors and recommended by the Northern Virginia Bird Alliance. The goal is to avoid mowing during grassland birds’ spring and early summer nesting season. This area has not been mowed since September 2023. By letting the grasses grow, managers have in effect created a grassland. Butcher comments, “I’ve spent a lot of time and energy working with the people at the landfill because it has the largest patch of grassland in eastern Fairfax County.”
Grassland birds are “among the fastest-declining bird species in the U.S., with a 34 percent loss since 1970,” a National Audubon Society 2022 report concluded. “The landfill supports populations of five key eastern grassland bird species,” Butcher reports.
Preparing a Plan
Blair Evancho, a May college graduate and county intern, and Carlos Leiva, a county employee, are conducting bird surveys, especially identifying birds that are “regionally rare and specialize in grasslands,” explains Evancho. “This habitat supports species that are not supported elsewhere.”
In other words, the point is not just the total number of birds or species, but documenting birds not typically found in other area habitats. Other grassland birds they have seen include Eastern meadowlarks, grasshopper sparrows and dickcissels. Butcher calls the dickcissel “a Midwestern bird.”
The landfill is in fact an Ebird hotspot, with at least 126 species identified over the last 15 years, most not grassland birds. On Sept. 5, vultures soared and crows called. Observers spotted Eastern phoebes and American kestrels. On July 31, Butcher confirmed 13 species, including wild turkeys, common ravens and chimney swifts.
On Sept. 5, the no-mow area was alive with insects, including butterflies (monarchs, cloudless sulfur, cabbage and tiger and black swallowtail), beetles, bees and dragonflies. “There are grasshoppers everywhere,” Evancho observed.
The area has a mix of wildflowers, native grasses and lespedeza. Bright yellow bearded beggar tick and Queen Anne’s lace plants punctuated the landscape as fox tail grasses swayed in the breeze. Bull thistles were shedding their seeds. Goldfinches use these seeds for building nests in August, said Butcher. “This is when seeds are available.”
Fairfax County official Eric Forbes touts the county’s “sustainability-minded management.”
“We planted our first native meadows at the site in 2016 for pollinators and wildlife, now we are managing traditionally mowed turf areas to allow for grassland bird nesting,” Forbes says.
“Hopefully we can show that altering our mowing schedule will allow native birds to breed, setting an example that helps our department’s sustainable community goal and meets our environmental compliance requirements for landfill management. This project can change how landfill operators and regulators manage mowed turf areas to allow for harmony with native bird species and other critical wildlife.” Forbes is Deputy Director, Solid Waste Management Program of the Department of Public Works and Environmental Services.
Evancho will analyze his data and prepare management protocols for the 50 acres. The Smithsonian’s Virginia Working Landscapes recommends Feb. 15 to April 1 as the “optimal time for field management” to protect breeding and nesting grassland birds.
Meanwhile, this part of the landfill is becoming a rare and rich grassland.