Wildlife & Habitat

  • American Bald Eagle

    American bald eagle - Bill Wallen.

    At the time of E.H. Mason Neck NWR’s establishment in 1969, the number of nesting bald eagles pairs had plummeted to less than 500 in the lower 48 states, prompting the bald eagle to be placed on the endangered species list. In 2007, the bald eagle was removed from the endangered species list due to significant population recovery. Even though the bald eagles have made a remarkable comeback, management of the refuge continues to focus on promoting nesting, feeding, and roosting habitat to ensure a stable future for eagles. The refuge provides ample viewing opportunities of bald eagles year-round.

  • Great Blue Heron

    Great blue heron - John Eppler.

    During the spring and summer months, the refuge hosts one of the largest heron nesting rookeries on the Potomac River. The rookery currently supports well over 500 active nests. To help support this large breeding population of herons, water levels in the adjacent 50-acre wetland are seasonally managed via a water control structure. This water manipulation is used to promote accessible foraging areas to adult and fledgling herons during the summer. Great Blue Herons can be seen on the refuge year-round foraging near marsh and wetland areas.

  • White-tailed Deer

    White-tailed deer - USFWS.

    White-tailed deer can be found at the refuge year-round. The large population of white-tailed deer provides hunting opportunities to the public on the refuge and State Park lands in the fall. Hunting is a valuable management tool that refuge managers use to keep the herd at an ecologically sustainable level to benefit all wildlife. Although numerous at the refuge, deer are well camouflaged and can often sense humans before being seen, taking the opportunity to flee. Look for signs such as hoof tracks or antler rubs on small trees along the trails to know of their presence.

  • The Great Marsh

    The Great Marsh - Bill Wallen.

    At 250 acres, this fresh water marsh is one of the largest on the Potomac River. The appearance of the marsh changes dramatically through watch season of the year. In summer, dragonflies streak across a blanket of pond lilies. You can find active beaver lodges with freshly cut sticks and an occasional muskrat roaming about. Fruiting wild rice, an important food source for wintering waterfowl can be seen in tall clusters. Through the fall and spring, migrating ducks, raptors, and songbirds stop at the marsh to rest on their long journey. During the winter, snow white tundra swans are joined by large numbers of ducks and Canada geese.

  • Forest


    Upland hardwood forest is the predominant vegetation type on the Mason Neck peninsula. Thirty-six species of trees have been recorded within the 1,883 acres of forest. Dominant species include Virginia pine, oaks, hickories, beech, and maple species. The forest habitat provides bald eagles roosting and nesting habitat during the winter months. In the spring and summer, visitors hike the woodland trails to hear woodthrush and ovenbirds singing or frogs calling from vernal pools. Autumn colors the forest with shades of yellow, orange and red as forest dwelling birds depart for southern grounds and warmer climates.