Silver Lake National Wildlife Refuge in North Dakota's Benson and Ramsey counties is part of the Devils Lake Wetland Management District and operates as an easement refuge rather than federally owned public land. The U.S. Fish and Wildlife Service manages wildlife habitat there while the property remains privately owned. This model emerged in the nineteen thirties and nineteen forties as declining waterfowl populations prompted conservation efforts that also provided work during the Great Depression. At Silver Lake, landowners sold easements allowing the government to regulate water levels and restrict hunting. The refuge itself is not open to public access, though wildlife may be viewed from nearby public roads.