The Loss of Habitat in Puget Sound Loss of River Delta Habitat River deltas are an integral part of the Puget Sound ecosystem. Their wetland inhabitants have provided an important source of food for humans for over 7,000 years.
Deltas are usually fan-shaped deposits of sediment that form where currents slow at a river's mouth.
Deltaic tidal wetlands generally extend from salt-water to freshwater marsh. Sloughs that dissect the marsh attract an abundance and diversity of life and serve as nursery areas for young fish. These wetlands are essential for nesting, wintering and feeding of waterfowl and shore birds. They also help stabilize shorelines, reduce erosion, and buffer the force of storms and floods. Deltas in the Puget Sound region attracted early development because they were flat, relatively unforested land close to the water.