Blackwater National Wildlife Refuge (NWR), located in the Blackwater and Nanticoke River watersheds on Maryland's Eastern Shore, preserves over 26,000 acres as a wintering area for vast numbers of migratory birds. It also serves as a haven for several threatened or endangered species, including one of the largest concentrations of nesting bald eagles along the Atlantic Coast. While primarily a tidal marsh, the refuge also includes a mature pine forest.

Before its designation as a Refuge, the marshland along Blackwater River was managed as a fur farm. Muskrats were the primary species trapped. Most of the wood-lands, including islands, had been timbered. Remains of old drainage ditches and furrows which crisscross in some existing woods indicate past agricultural use.