Esther Island is an island in the northwestern part of Prince William Sound

Prince William Sound

Prince William Sound is a sound off the Gulf of Alaska on the south coast of the U.S. state of Alaska. It is located on the east side of the Kenai Peninsula. Its largest port is Valdez, at the southern terminus of the Trans-Alaska Pipeline System...

 of the Gulf of Alaska

Gulf of Alaska

The Gulf of Alaska is an arm of the Pacific Ocean defined by the curve of the southern coast of Alaska, stretching from the Alaska Peninsula and Kodiak Island in the west to the Alexander Archipelago in the east, where Glacier Bay and the Inside Passage are found.The entire shoreline of the Gulf is...

 in the state of Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

, USA. It has a land area of 127.336 km² (49.165 sq mi) and a resident population of 31 persons as of the 2000 census

United States Census, 2000

The Twenty-second United States Census, known as Census 2000 and conducted by the Census Bureau, determined the resident population of the United States on April 1, 2000, to be 281,421,906, an increase of 13.2% over the 248,709,873 persons enumerated during the 1990 Census...

. The island is the site of the South Esther Island State Marine Park, one of the Alaska State Parks system. The island includes no permanent settlements other than the Wally Noerenberg Hatchery, one of the world's largest Salmon hatcheries

Hatchery

A hatchery is a facility where eggs are hatched under artificial conditions, especially those of fish or poultry. It may be used for ex-situ conservation purposes, i.e. to breed rare or endangered species under controlled conditions; alternatively, it may be for economic reasons A hatchery is a...

, owned and operated by the Prince William Sound Aquaculture Corporation (PWSAC). The hatchery raises three different species of salmon Pink salmon

Pink salmon

Pink salmon or humpback salmon, Oncorhynchus gorbuscha, is a species of anadromous fish in the salmon family. It is the smallest and most abundant of the Pacific salmon.- Appearance :...

, Chum salmon

Chum salmon

The chum salmon, Oncorhynchus keta, is a species of anadromous fish in the salmon family. It is a Pacific salmon, and may also be known as dog salmon or Keta salmon, and is often marketed under the name Silverbrite salmon...

, and Coho salmon

Coho salmon

The Coho salmon, Oncorhynchus kisutch, is a species of anadromous fish in the salmon family. Coho salmon are also known as silver salmon or "silvers". It is the state animal of Chiba, Japan.-Description:...

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The hatchery is located within the State Marine Park. The island is only accessible by floatplane or boat.