The watershed drained by the river and its tributaries measures approximately 568 square miles, and is composed primarily of pine forests and scrub habitat.

The lower reaches of the river form an extensive wetlands area, which is protected on its southern bank as the Edwin B. Forsythe National Wildlife Refuge.

Blue claw crabs are prevalent in the lower reaches of the river and in tributaries flowing through the surrounding salt marshes.

These tidal creeks also support populations of the northern diamondback terrapin, which is listed by the federal government as a species of special concern.

Canada geese, American black ducks, mallards, tundra swans, northern pintails, and other migratory birds are often observed in the river estuary.