The Russell W. Peterson Urban Wildlife Refuge stands on the former Old Wilmington Marsh, also called Dravo Marsh, a 238-acre freshwater marsh on the Christina River renamed for former Delaware Governor Russell W. Peterson, a nationally prominent environmentalist known as "Rebel with a Conscience." His vision led to redevelopment of this riverfront, and during his service as governor from 1969 to 1973 he championed the Coastal Zone Act; he also served as president of the National Audubon Society. Peterson's environmental leadership over more than fifty years inspired the conviction that this refuge can again become a thriving fish and wildlife area, with tidal freshwater wetlands supporting diverse vegetation and habitat for migratory waterfowl and other water birds, including black ducks, pintails, green-winged teal, migrant Canada geese, and various heron and raptor species, as well as mammals such as muskrats, beaver, and otter.