Sea level rise is already impacting Blackwater National Wildlife Refuge (NWR), located on Maryland’s Eastern Shore, where two bird species are declining rapidly as their marsh habitat sinks beneath the water’s surface. The black rail was recently listed as endangered in the state of Maryland because a survey of this species in 2006 found that it had declined more than 85% since the early 1990s. The saltmarsh sparrow lives only in tidal salt marshes in the eastern United States and its population, estimated at just 53,000, is declining at an alarming 9% per year.

Stemming a Rising Tide

The U.S. Fish and Wildlife Service, The Conservation Fund and the National Audubon Society have joined forces in an ambitious effort to build up these vital marsh lands at Blackwater NWR. Begun in 2016, this project has used 26,000 cubic yards of sediment from the Blackwater River to raise the marsh surface in a process called “thin-layering.” The newly “just-right” level of this 40-acre marsh site will invigorate the growth of native marsh grasses.

We provided funding through a grant from the National Fish and Wildlife Foundation’s Hurricane Sandy Coastal Resiliency Competitive Grants Program, appropriated by Congress and supported by the refuge’s congressional delegation: U.S. senators Barbara Mikulski and Ben Cardin and U.S. Representative Andy Harris.

This restoration project is one strategy for marsh resilience outlined in Blackwater 2100, a report we published in 2012 with Audubon Maryland-DC that prescribes a suite of strategies to address the forecasted marsh loss in Blackwater NWR’s home of Dorchester County through the end of the century.

We have been active at Blackwater NWR for more than a decade. We’ve protected nearly 8,000 acres at the refuge — including lands that complement the Harriet Tubman Underground Railroad National Monument — and planted 10,000 native trees to restore 40 acres of high-priority upland on the refuge.

Why This Project Matters

This is the largest wetland restoration project at Blackwater NWR and the first thin-layer project in the Chesapeake watershed. Raising the surface of the marsh by 4-6 inches should add several decades to the life of the marsh by stimulating more plant growth above and, importantly, below the marsh surface to prevent constant tidal flooding that would kill off marsh grasses. Restored, the high tidal marsh is the preferred habitat of black rails and saltmarsh sparrows.