Aunu'u is a small volcanic island off the southeastern shore of Tutuila

Tutuila

Tutuila is the largest and the main island of American Samoa in the archipelago of Samoan Islands. It is the third largest island in the Samoan Islands chain of the Central Pacific located roughly northeast of Brisbane, Australia and over northeast of Fiji. It contains a large, natural harbor,...

 in American Samoa

American Samoa

American Samoa is an unincorporated territory of the United States located in the South Pacific Ocean, southeast of the sovereign state of Samoa...

. It has a land area of 374.83 acre (0.585672392835811 sq mi; 1.52 km²) and a 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...

 population of 476 persons. Politically it is a part of the Eastern District

Eastern District, American Samoa

The Eastern District is one of the primary divisions of American Samoa. It consists of the eastern portion of Tutuila, American Samoa's largest island, plus the island of Aunu'u. The district has a land area of 67.027 km² and a 2000 census population of 23,441. It contains 34 villages plus a...

, one of the primary divisions of American Samoa.

Faimulivai Marsh is a freshwater marsh in Aunu'u Crater and the largest such wetland in American Samoa. It was formed from drainage of the low-lying crater. It is part of a protected National Natural Landmark

National Natural Landmark

The National Natural Landmark program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only natural areas program of national scope that identifies and recognizes the best examples of biological and geological features in...

 on Aunu'u which was designated in 1972. The Pacific Black Duck

Pacific Black Duck

The Pacific Black Duck is a dabbling duck found in much of Indonesia, New Guinea, Australia, New Zealand, and many islands in the southwestern Pacific, reaching to the Caroline Islands in the north and French Polynesia in the east. It is usually called the Grey Duck in New Zealand...

 was seen in the marsh in 1976, but it may now be extinct in the region; another significant local bird is the Purple Swamphen

Purple Swamphen

The Purple Swamphen , also known as the African Purple Swamphen, Purple Moorhen, Purple Gallinule, Pūkeko or Purple Coot, is a large bird in the family Rallidae . From its name in French, talève sultane, it is also known as the Sultana Bird...

. This marsh is the only place in American Samoa that has Chinese water chestnut

Eleocharis dulcis

The Chinese water chestnut , more often called simply the water chestnut, is a grass-like sedge grown for its edible corms. The water chestnut is actually not a nut at all, but an aquatic vegetable that grows in marshes, underwater in the mud...

.^{http://www.unep-wcmc.org/sites/wetlands/wet_aunu.htm}