Kachemak Bay is a 64-km-long (40 mile) arm of Cook Inlet in Alaska, located on the southwest side of the Kenai Peninsula. There is no road access to most of the park; visitors must arrive by airplane or boat to see the home of beluga whales.
Kachemak Bay is also home to the Kachemak Bay National Estuarine Research Reserve, the largest reserve in the National Estuarine Research Reserve System. It is a very active site of research and education. The bay hosts a remarkably high level of biological activity, due in part to water circulation patterns which keep shellfish larve and nutrients in the bay. While surface waters push nutrients out into the bay, ocean currents push them back into the bay, creating a very fertile environment. Both fish and shellfish are abundant in the bay, year-round. Waterfowl and shorebirds occupy the bay during all but the winter season, while waterbirds and marine mammals including otters, seals, porpoise, and whales remain in the bay all year. The bay provides winter homes for 90% of the seabird and waterfowl populations of Lower Cook Inlet. Land mammals are frequently seen during the warmer seasons. Moose, coyote, and bears are frequently seen.
The tides at Kachemak Bay are extreme, with an average vertical difference of 15.53 feet (4.73m), and recorded extremes of 31.72 feet (9.67m).