Kachemak Bay
Critical Habitat Area

A component of An International Reserve of the Western Hemisphere shorebird reserve Network and The Kachemak Bay National Estuarine Research Reserve

Easy access, outstanding recreational opportunities, and a diverse and productive environment make Kachemak Bay important to residents and visitors alike. Fish and shellfish populations abound year-round, supporting several significant fisheries. In the spring, summer, and fall, the bay hosts tens of thousands of feeding waterfowl, shorebirds, and seabirds. In the winter, marine mammals and waterbirds remain in the bay's protected waters.

The high level of biological productivity in Kachemak Bay is at least partially the result of a large gyre-like circulation pattern that serves to hold shellfish larvae in the bay. Productivity is further enhanced by a two-layered "nutrient trap" estuarine system in which organic nutrients are moved out of the bay by surface waters and settle to the bottom only to be moved back into the bay by deeper on-shore currents.

Birds - The greatest concentrations of birds occur during the spring and fall migration when large flocks of geese, ducks, and shorebirds move through the bay and its associated wetlands. Most of these spring and fall concentrations use traditional staging areas at the head of the bay on the Fox River Flats.

During the spring and summer months, outer Kachemak Bay and nearby waters support the highest seabird densities in Cook Inlet. Gull Island, Grass Island, 60-foot Rock, Hesketh Island, and Point Pogibshi provide nesting habitat for tufted puffins, horned puffins, pigeon guillemots, black-legged kittiwakes, glaucous-winged gulls, and common murres. In addition, Kachemak Bay accommodates 90 percent of the overwintering seabird and waterfowl populations of Lower Cook Inlet.

Mammals - Mink and river otters forage along the beaches feeding on marine invertebrates and nearshore fish. Coyote, fox, and an occasional black or brown bear visit the beaches in search of carrion or prey. The shallow and productive nearshore waters along the rocky southern shore provide habitat for sea otters.

Dall porpoise and harbor porpoise commonly feed in the bay. The Dall porpoise is often sighted chasing the bow wake of boats. Harbor seals have been observed at hauling-out areas on Yukon Island, with lesser numbers reported on the Bradley River Flats and several rocks on the southern boundary of the bay. Sea lions, killer whales (orca), beluga whales, and minke whales are commonly found in Kachemak Bay. Occasionally humpback and finback whales and walrus are sighted.

Fish and Marine Invertebrates - Kachemak Bay supports some of the richest marine invertebrate communities in all of Cook Inlet. Sea ducks, diving ducks, shorebirds, marine fish, and small mammals feed heavily upon the clams, mussels, snails, worms, and other marine invertebrates found on the mudflats and rocky/gravel beaches of inner Kachemak Bay. The south side of Kachemak Bay is lined with rocky shores and kelp beds interspersed with pocket beaches of sand and gravel, which support productive intertidal and subtidal marine life. The north side of Kachemak Bay including the Homer Spit is composed primarily of gravel and sand. Razor, cockle, and red-necked clams can be found there.

Kachemak Bay is an important fish and shellfish rearing area, with historical abundance of herring; salmon; halibut; king, Tanner, and Dungeness crab; and pink, spot, humpy, side-stripe, and coon-stripe shrimp.

Public Use and Access - Homer Spit is the main access point to the bay, with access also gained through Seldovia and other small communities. In the summer, sport fishing for halibut and salmon and wildlife watching tours are very popular, as is clamming on low tides throughout the year. Halibut and salmon are the mainstays of the local commercial fisheries as well. The pristine protected waters on the south side of the bay have attracted interest in mariculture.

For more information on Kachemak Bay please refer to the Kachemak Bay Management Plan (PDF file 840 K).