Marsh at Blackwater National Wildlife Refuge is widely known as a stopover for migratory birds. What may be lesser known is that the marsh itself is migrating.
Since 1938, the Maryland refuge has lost 5,000 acres of brackish marsh—and 3,000 upland acres have converted to brackish marsh. A new strategy to address sea–level rise, called the Southern Dorchester County Climate Adaptation Project, is working to facilitate this “marsh migration.”
“If Blackwater is going to be successful at meeting its established purposes” as a waterfowl sanctuary along the Atlantic Flyway, says refuge biologist Matt Whitbeck, “we have to have wetlands, and we have to understand how to help marshes migrate across the landscape. We don’t claim to understand how this is going to work. It’s very much in the experimental stage—an adaptive management process.”
The goal of the project—a partnership among the U.S. Fish and Wildlife Service, The Conservation Fund and Audubon Maryland/DC—is to maintain the ecological functions of the salt marsh somewhere on the landscape. The refuge is part of the Northeast’s most extensive contiguous tidal marsh, a Ramsar Wetlands of International Importance and an Audubon Important Bird Area for salt marsh bird species. Audubon Maryland/DC director of bird conservation Dave Curson has called the refuge “Maryland’s Everglades.”
The tiny saltmarsh sparrow, whose primary range is the northeastern United States and Canada, is directly affected by sea–level rise, as are black rails, clapper rails and seaside sparrows.
“If we want these species to persist, we have to adapt to these changes,” says Whitbeck. “The saltmarsh sparrow is just one piece of the puzzle. As we evaluate how these systems migrate across the landscape, we have to know how all the pieces will move as well.
It’s responsible stewardship to hang on to all the pieces.”
And all the pieces are connected. The salt marsh provides vital nursery grounds for commercial fisheries, generates $27 million in annual revenue from tourism/recreation, creates a buffer for communities against storm surges, and filters sediment and nutrient pollution in the Chesapeake Bay watershed.
The salt marsh birds are among the keystone species in the Strategic Habitat Conservation Plan for the Chesapeake Marshlands Refuge Complex, which includes Blackwater Refuge. The landscape–level, across–boundary actions taken and the lessons learned in the Southern Dorchester County Climate Adaptation Project may be a model for other coastal zones confronting sea–level rise.
The project is in the second year of a grant cycle that provided $265,000 from Maryland’s Town Creek Foundation. Using the Sea Level Affecting Marshes Model (SLAMM) and other factors, the project identified where the “largest jaw–dropping contiguous areas of high marsh habitat are likely to be over the next century,” Whitbeck says. “We will control what we can and work with the changes we can’t control.”
Two examples illustrate the project’s approach. The first is biological, the second outreach–related.
Traditionally, refuge managers have removed phragmites from established marsh. Now, before that invasive reed can take hold, herbicides are used to remove it from areas to which marsh is migrating. Then, students and Friends help plant native species there. “If we can manage phragmites in transition, we might be able to improve more acres with the same amount of resources,” says Whitbeck.
Regarding outreach, Samantha Pitts, Audubon Maryland/DC volunteer coordinator and naturalist, is using social media, educational programs and field trips to build support for salt marshes. The local Pickering Creek Audubon Center’s Facebook page, for example, features educational posts about Atlantic Flyway salt marshes on Marsh Mondays.
“It’s important for communities to have their own connection with where they live,” says Pitts, “Blackwater is the epicenter for salt marshes on the East Coast. We are trying to reach people and connect them with the resource.”
Karen Leggett is a writer–editor in the Refuge System Branch of Communications.
