Mason Neck is adjacent to a rapidly growing metropolitan area where habitat is constantly being altered and degraded. The refuge, which extends out into the Potomac River, provides a relatively remote area of upland forests and freshwater marshes which are frequented by a diverse group of wildlife species. The monotypic mature upland hardwoods, freshwater marshes, and small grassland areas which comprise the Refuge habitat hosts over 211 species of birds, 31 species of mammals, and 44 species of reptiles and amphibians.
List of Birds of the Mason Neck Area (PDF 13Kb)
Salamanders, Frogs, and Toads
Eastern worm snake
Of 45 species of mammal that may occur on Mason Neck based on the presence of suitable habitat, a study conducted in 1995 confirmed the existence of 28. The black bear and bobcat were present at one time but their recent occurrence on Mason Neck is doubtful. The following mammals have been spotted and/or collected on Mason Neck NWR (Klimkiewicz et al, Year Unknown).