Copper River Delta

The Copper River Delta Shorebird Reserve Unit near Cordova, Alaska, was the first Alaska shorebird habitat to be included in the Western Hemisphere Shorebird Reserve Network.  It is an area of great diversity that offers essential habitats for shorebirds and other wildlife from early spring through late fall. The site comprises intertidal and submerged lands in Orca Inlet and on the delta front of the Copper River includes extensive glacial outwash plains, uplifted marshes, intertidal mudflats and wetlands, tidal sloughs, and barrier islands and spits. Wetland habitats surrounding the WHSRN site extend from the foot of the Chugach Mountains to the tidal flats inside the barrier islands. Between the mountains and the estuarine area is a belt of sedge meadows, ponds, willow and sweetgale shrubs, and vegetated wetlands bordered with alder and cottonwood along streams.

As many as 1.1 million shorebirds have been observed at one time using the Copper River Delta during the peak migration (April 25 – May 15). The majority of Western Sandpipers and Dunlin (Calidris alpina pacifica), the two most abundant species of shorebirds on the Pacific Coast, stop here each year before flying further north and west to their breeding grounds. Their presence on estuarine mudflats behind the barrier islands is, by far, the most impressive use of Copper River habitats by shorebirds. Obtaining the necessary energy reserves on the Delta greatly influences their reproductive success elsewhere in Alaska and/or Siberia. Important too are the upland marsh wetlands for other shorebird species breeding here.

In addition to stopover habitat, the wetlands on the Delta provide a variety of shorebird nesting habitat. Nesting species include: Short-billed Dowitcher, Least Sandpiper, Greater Yellowleg, Wilson’s Snipe, Red-necked Phalarope, Spotted Sandpiper, and Semipalmated Plover. Less common Delta breeders include Lesser Yellowlegs.

The Copper River Delta Cooperative Agreement was signed in 1962. In 1971 some lands were transferred to local Alaska Native regional and village corporations.  In 1978, the State of Alaska legislature designated much of the tidal, submerged, and adjacent uplands as the Copper River Delta State Critical Habitat Area, to be protected and conserved by the Alaska Department of Fish and Game. A five-party Memorandum of Understanding (MOU) signed in 1986 established the Copper River Delta Fish and Wildlife Management Area, enlarging the former agreement and facilitating cooperation between State and Federal agencies in research and management programs for the area. In 1990, an MOU established the Copper River Delta Shorebird Unit (CRDSU), reflecting a combined concern for shorebirds by state and federal public agencies, Alaska Native corporate land owners, and the local city government. The CRDSU focuses attention on the Delta as a key staging area for shorebirds.

Much of the site is managed by the U.S. Forest Service (Chugach National Forest) through the Cordova Ranger District for the conservation of fish and wildlife and their habitats, in accordance with the Alaska National Interest Lands Conservation Act (ANILCA, passed in 1980). Remaining lands are managed by the City of Cordova, State of Alaska, Eyak Corporation, and the Chugach Alaska Corporation.

The USFS Cordova Ranger District staff members and a broad base of cooperators conduct plant association and ecology work, management studies, and fish and wildlife research, and habitat improvement projects throughout the Delta.

The Copper River Delta is part of the U.S. Forest Service’s Key Coastal Wetlands network in Alaska. Managers and researchers are tracking habitat changes occurring at coastal wetlands, which are so susceptible to effects of glacial rebound, earthquake uplift, and climate change, to better understand and manage for these pressures. The Copper River International Migratory Bird Initiative (CRIMBI) links the Copper River Delta with a variety of partners within the United States and Latin America. This initiative strengthens conservation, research, education, and funding for the Copper River area’s migratory bird resources through effective international partnerships, outreach, and on-the-ground action.

The Prince William Sound Science Center, a non-profit research and education organization located in Cordova, Alaska also conducts shorebird research on the Copper River Delta and in Prince William Sound. The Science Center’s radio telemetry studies have documented the critical importance of the Copper River Delta complex during spring to Red Knot, Dunlin, Western Sandpiper, Short-billed Dowitcher and Long-billed Dowitcher.

On October 9, 1999 the Western Hemisphere Shorebird Reserve Network recognized the Altamaha River Delta in Glynn and McIntosh Counties as the 40th major reserve for shorebirds, highlighting its importance as a stopover for migratory and wintering birds traveling between the Arctic and South America. The Georgia Department of Natural Resources estimates this area supports at least 55,000 seabirds and shorebirds annually, stating “There are very few places as valuable to such a large and diverse number of coastal birds in all the southeast United States.”

Prominent features of the delta include sand spit and barrier islands to the north and south with extensive barrier beaches, dunes, maritime forest and salt marshes. The islands and their associated habitats offer exceptional habitat for breeding and wintering birds. The surrounding waters and wetlands provide a readily available food source. The area serves as a resting site for migrating shorebirds, waterbirds and landbirds, including high concentrations of American Oystercatcher (migration/winter: 250), Red Knot (migration 5,000), Dunlin (migration 1,500) and Piping Plover (migration/winter: 65).