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Resource Management

Impoundment

Management activities at Back Bay National Wildlife Refuge are focused on providing feeding and resting habitats for migrating and wintering waterfowl. These habitats include an 870 acre freshwater impoundment complex. This man-made wetlands provides ideal waterfowl feeding and resting areas. Refuge staff also monitor the Bay’s extensive natural beds of submerged aquatic vegetation (SAV), monitor waterbird population use of Refuge habitats; control non-native, invasive weeds; and manage 117 acres of reforested woodlands to encourage successful maturation of planted tupelos, green ash, Bald cypress and water oaks. These actions provide the best habitat possible for refuge wildlife and insure their continued use of Back Bay’s extensive wildlife resources.

The freshwater impoundment complex consists of ten impoundments are managed for waterfowl, shorebirds and wading birds at different times of year. Water levels are raised and lowered throughout the year using water pumped in from Back Bay. Spring and fall draw-downs create mudflats for use by migrating shorebirds. Deeper waters are preferred by wading birds (egrets and herons) and wintering waterfowl (ducks, geese and the tundra swan). When water quality conditions in the Back Bay are unsuitable for waterfowl, fish and other organisms, the impoundment complex provides an alternative habitat for them. 

Underwater grasses, SAV, provide the foundation for Back Bay’s food-chain. During the mid to late 1980’s Back Bay’s extensive SAV beds crashed and disappeared, creating a sterile underwater landscape. With no SAV foods available, migrating and wintering waterfowl could not use the Bay as a feeding ground; the Bay’s largemouth bass nurseries declined; and other invertebrates and SAV dependent organisms were similarly unable to survive. Since then the Refuge and its partners have successfully encouraged changes to land use patterns within the Back Bay Watershed that may be credited with the current return of extensive SAV beds, together with dependent waterfowl, fish and invertebrate populations.

Over two hundred species of birds can be found at Back Bay NWR. Many of these birds are waterfowl, shorebirds or marshbirds. Biologists conduct surveys all year in the impoundments, along the beach and aerially over the Bay during winter, to assess the numbers of birds using the Refuge and surrounding areas. Assessment of these surveys provides trend information, useful in determining waterbird migration patterns and/or population peaks and lows by species. Such information is useful for helping Refuge biologists determine if current management is achieving management objectives to benefit our trust species or not.

Have you heard of kudzu or English ivy? These are two invasive species present in many areas in the United States. At Back Bay NWR one serious invasive pest is the tall common reed (Phragmites australis). This tough, sharp-leaved reed can reproduce by rhizomes or seed, quickly spreading into disturbed areas and displacing diverse native marsh plants. Biologists at Back Bay NWR and other local, state and private organizations have been monitoring and striving to control the common reed invasion of the Back Bay Watershed for years. Large-scale cooperative efforts have been undertaken to control its spread and allow native vegetation to again thrive in the landscape. Other invasive species on the Refuge include feral hogs and nutria.

As with most landscapes on the East Coast of the United States, the Back Bay Watershed and Back Bay NWR have been changed by human activity. In Refuge lands to the north and west of Back Bay deforestation removed large numbers of once prominent hardwood trees, including oaks, tupelos, sycamores and Bald cypress. Fast-growing loblolly pines filled the gap, reducing the unique forest diversity that once existed. Refuge biologists have reforested many of these areas, recreating hardwood forests of the past.

Last Updated: Feb 12, 2013
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