Lesser celandine, with its a small, pale yellow blossoms, looks like an innocuous plant. But the sprawling weed crowds out native species when it blooms in spring and then goes dormant, leaving ground brown and bare through summer and fall. Normally at this time of year, volunteers with the New York New Jersey Trail Conference's Invasives Strike Force would be pulling up the species and other invasive plants during weekend meet-ups. This year, however, is anything but normal—the group suspended work on March 23.
Across the country this spring as the COVID-19 pandemic has taken hold, conservation organizations and government agencies have postponed or canceled projects that require groups to meet and work together. Although public health is everyone's firm priority, gaps in invasive species removal, controlled burns, and habitat restoration can create short- and long-term setbacks to time-sensitive projects.
Skipping a season of invasive removals, for example, can allow plants to produce seeds that spread—undoing years of work, says Linda Rohleder, director of land stewardship at the Trail Conference. The seeds of the invasive herb garlic mustard are viable for five to seven years, she notes. "Year after year, you're trying to eradicate a population," she says. “If you miss a year, and it goes to seed, then now you've set back your project five to seven years.” In the arid west, another concern is the ground hardening as summer sets in, making invasive removals or plantings nearly impossible, says Andrea Jones, Audubon California’s director of bird conservation.
Prescribed burns—deliberate fires started to clear excess tree and grass growth—have also been suspended in some states, setting off some concerns for the upcoming wildfire season. In mid-March, the U.S. Forest Service announced that all new ignitions were postponed until further notice, but they have since walked that back to say there is no agency-wide pause. The U.S. Bureau of Land Management is proceeding with burns as long as they can be done safely, a representative told Audubon by email.
Fire is an essential tool not only for controlling wildfire risk, but also for managing habitat for wildlife—especially in prairie ecosystems, says Daniel Suarez, the stewardship program manager at Audubon Great Lakes. His team has canceled prescribed burns that help keep invasive plants in check in both grasslands and wetlands, in part because of social distancing requirements, but also because burns can increase local air pollution at a time when people with respiratory illnesses, including COVID-19, need to stay healthy.
Birds may eventually feel trickle-down effects of this canceled work. When trees like the callery pear are allowed to flourish and spread, Suarez explains, they give predators a place to hide and to pick off vulnerable grassland birds, like the Bobolink and the Henslow's Sparrow, two of the fastest declining grassland birds in the eastern United States. The burn window is already short in the upper Midwest—it falls between the last snowstorm and the first warm days that bring snakes and amphibians out of hibernation—so the region is likely to miss out this year. And after birds like the Bobolink start nesting, people can’t go out to remove invasive shrubs by hand without risking crushing the nests underfoot.
Elsewhere, the pressing need is replanting habitat to provide birds with more cover. In central Pennsylvania, the nonprofit ClearWater Conservancy has postponed or canceled events to replant riparian buffers—the forested or grassy strips of land on sides of streams and rivers—which provide shelter for wildlife and help reduce erosion. And John Parodi, a restoration manager at the California-based nonprofit conservation organization Point Blue, says that right now they should be revegetating high ground around tidal marshes in the San Francisco Bay, where birds like the Ridgway's Rail can retreat from predators when the tide comes in. Currently, much of that land is either bare or covered in weeds that die off and leave the ground exposed all winter. Rising sea levels makes this work all the more pressing, he says.
Large restoration projects are also vulnerable to the disruption. In the Great Lakes region, where a minuscule fraction of original prairie remains, seeding new prairie is the usual focus. "The lion's share of the work is happening on the acres that used to be corn fields," Suarez says. "The work that we're doing is really time sensitive . . . the first five years of a project are going to dictate what your prairie looks like in year 20."
Not all habitat management work is so urgent, however. Jenny Dickson, the director of Connecticut’s Wildlife Division, says that all activities not connected to outdoor recreation have been put on hold. “At the end of the day, we will still be able to do those projects,” Dickson says. “It's just gonna have to take a little while before we get there.” In the meantime, she says, some key work has been deemed essential—such as putting up string fences to protect Piping Plover nesting areas from trampling crowds—but is just proceeding more slowly than usual.
Current restrictions on movement and group gatherings may eventually affect projects scheduled for later this year. Ryan Burnett, who coordinates meadow restoration in the Sierra Nevada for Point Blue, says their field season is in the fall. However, because many projects are on federal land, they’d planned to conduct required environmental impact assessments beforehand. The work, he says, is part of a “fast-paced” 10-year goal to make habitat more resilient to a warming climate, and they don’t have a year to lose. "Climate change is also not sheltering in place," says Burnett. "It's going to keep coming."