The Palmer Hay Flats IBA is located at the north end of Cook Inlet at the head of the Knik Arm, approximately 25 miles north of Anchorage. The site encompasses a complex of forest, wetlands, tidal sloughs, lakes and tideflats at the mouths of the Knik and Matanuska rivers. Marsh and bog communities predominate. The area subsided in the 1964 earthquake, before which it supported a drier grassland habitat.

Ornithological Summary

Because of its estuarine nature, waterfowl are particularly attracted to this IBA. Over 100,000 ducks, 50,000 geese and 5000 swans use the refuge in the spring. Fall use drops to about 50,000 ducks, 10,000 geese and 15,000 swans [4]. In the spring when breakup is late and estuarine habitats in southern Cook Inlet are unavailable, this site is extremely important to waterfowl.

Palmer Hay Flats was identified as part of a potential Western Hemisphere Shorebird Reserve Network Regional Reserve site (the Knik River Flats site), using criteria of >20,000 birds or >5% of a species' flyway population [5].

Species of conservation concern that occur but do not meet criteria thresholds include the: Trumpeter swan; Barrow's Goldeneye; Golden eagle; and Blackpoll Warbler.

Waterbirds: passage; survey 1995; minimum number 15,901; 4bi

Canada Geese:
-Surveys in 1987-5,930; 1987- 12,424; 1985- 19,500; 1986- 4,800.

Snow Geese: 1985- 1,990l 1986- 2,000.

Conservation Issues

Disturbance to birds, animal/plant introduction, natural resource extraction industry, industrialization/urbanization, natural events, shifting agriculture.


Bird Conservation Region: Northwestern Interior Forest.
Sub BCR: Cook Inlet..


Mixed forests; scrub; tidal river/enclosed tidal water; mudflats/sandflats; standing fresh water; river/stream; blanket bog; sea inlet/coastal features; arable land.

Land Use

Hunting; nature conservation; tourism/recreation.

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