Wetlands

Arrowwood Mud Lake Aerial

Arrowwood Refuge straddles 16 miles of the James River, one of the longest unnavigable rivers in North America. It is a slow-moving, meandering, prairie river that drops only 1-2 inches per mile and, for its length, has been termed "the flattest river in North America." Due to the rivers low gradient, it creates four major water bodies as it meanders its way through the Refuge: Arrowwood, Mud and Jim Lakes and Depuy Marsh. Water within these naturally occurring riverine lakes is controlled by low dams and structures built by the Civilian Conservation Corp (CCC) in the early 1930s. 


 

Wetlands

Arrowwood Lake, the northernmost impoundment, covers 1,586 surface acres with depths to 5 feet. It is characterized as a large expanse of open water fringed with emergent vegetation. This impoundment is the most productive of the four wetlands and generally produces large amounts of sago pondweed. Sago pondweed shoots, tubers and the invertebrates it supports are an important food source for waterfowl, shorebirds and many other wildlife species, especially when nurturing broods. The shallow upper end of the lake and inlets of several creeks provide areas of tall, emergent vegetation which provide nesting habitat for herons, grebes, Franklins gulls, black terns and rails as well as foraging habitat for breeding and migratory ducks.
 

Arrowwood Lake and Grass FWS 150X118 

Mud Lake, the second wetland in the chain, consists of 719 acres of wetland habitats. The upper end is a series of river channel and back water areas with a mix of shallow open water interspersed with stands of cattail and other emergent vegetation. The center portion consists of three constructed sub-impoundments which are managed as moist soil units. These areas are used heavily for brood rearing by waterfowl and other water dependent birds. Moist soil vegetation also provides optimum habitat for migrating waterfowl and shorebirds. The lower reach of the lake is mostly open water, slightly deeper and fringed with emergent vegetation. Shallow mud flats present on the west shore of nearly the entire length of the lake are attractive to numerous shorebird species. 

 

The third impoundment is Jim Lake which has a water level two to three feet deeper than Arrowwood Lake. This limits light penetration and sago production. Lowering the pool late in the growing season produces a later bloom of sago pondweed which provides habitat for waterfowl throughout fall migration. Peak numbers of swan and diving ducks such as canvasback and lesser scaup, have exceeded 30,000 birds on Jim Lake. Islands, located in the south end of the lake and exposed during low water years, have been used by endangered piping plovers. 

 

Depuy Marsh located at the southern end of the refuge contains 377 acres which is subdivided into two moist soil units. Management objectives will focus on season-long habitat and providing foods for migrating shorebirds and waterfowl broods. In addition, the refuge contains approximately 600 acres of natural and man-made wetlands. These wetlands are comprised of various sizes and shapes of temporary, seasonal and semipermanant basins.