Millennia ago, glaciers sculpted the complex of waterways and islands known as southeast Alaska. Even today, the dynamic forces of glaciation are at work. These forces are evident in the Mendenhall Refuge. As the massive glaciers retreat up their carved valleys, rivers flow from the melting ice. Ground rock and silt carried by the rivers are deposited on the flats of Gastineau Channel. The Gastineau Channel, a glacial fjord estuary between Douglas Island and the mainland, extends from the south end of Douglas Island to the entrance of Fritz Cove and is approximately 18 miles in length. The width of the channel varies from 0.3 miles to 1.8 miles (DeLorme. Alaska Atlas.1992). The north end of the channel contains the Mendenhall Wetlands State Game Refuge, into which the Mendenhall River flows. The Gastineau Channel is important for human recreation and wildlife habitat. Each summer thousands of salmon and other fish are harvested in its waters. Crabbing, clamming and waterfowl hunting are popular in the wetlands along the channel. In the spring and summer, swimming and camping along the shores are common forms of recreation among residents.