The Black River Unit was established in 1996 and is managed as part of Billy Frank Jr. Nisqually National Wildlife Refuge. It encompasses a large mosaic of wetland and riparian habitats and surrounding uplands along the Black River. The purpose of the Unit is to protect biological diversity, enhance and manage unique wetland and riparian ecosystems for the benefit of anadromous salmonid production and rearing, migratory and resident waterfowl, migratory neotropical birds, wading birds and other wetland-dependent wildlife. The Black River is a tributary of the Chehalis River, the second largest watershed in Washington. The Unit's wetland habitats make up one of the largest, relatively undisturbed freshwater