Local facts and maps

Samoan Archipelago. This chain of 9 inhabited Pacific islands is located 14⁰ south of the equator and is divided into two political entities, the US Territory of American Samoa and the neighboring independent country of (western) Samoa. The youngest islands in this chain lie towards the east (Ta'u), contrary to an earlier geological report.

Territory of American Samoa. The total land area is 76.1 square miles and includes five volcanic islands (Tutuila, Aunu'u, Ofu, Olosega, Ta'u) and two remote atolls (Rose, Swains).

Population. Polynesians arrived here about 3,000 years ago. The current population (60,000 in 2002) is growing rapidly at 2.1% per year. Most people (96%) live on Tutuila Island. The ethnic composition is approximately 90% Samoan, 4% Tongan, 2% Caucasian, and 4% others.

Topography. The main islands are steep mountains that emerge from the ocean floor about 2-3 miles below the sea surface. Peak elevations are about 3,100 feet on Ta'u Island (Lata Mountain) and 2,142 feet on Tutuila Island (Matafao Peak).

Climate. Hot, humid and rainy year-round, but there is a long, wet summer season (October - May) and a slightly cooler and drier season (June - September). Total rainfall is 125 inches at the Tafuna airport and 200+ inches in mountainous areas.

Hurricanes. While very destructive, hurricanes (cyclones) are a natural feature of the environment in this part of the world. The most recent ones in American Samoa occurred in 1981 (Esau), 1987 (Tusi), 1990 (Ofa), and 1991 (Val).

Native flora and fauna. Most native species here are closely related to those in Indonesia. Due to our remote location in the Pacific Ocean, the diversity of terrestrial species here is low: 471 flowering plants and ferns, 24 resident land and water birds, 20 resident seabirds, 3 mammals (all bats), 7 skinks, 4 geckos, 2 sea turtles, 1 snake, and other occasional visitors. In contrast, the diversity of marine species here is high: 890 coral reef fishes, over 200 corals, and a few whales and dolphins. Insects and other invertebrate species here are not well known.

Endemic species. Species found only in the Samoan Archipelago include one bird (Samoan starling) and about 32% of local plant species. Five flowering plant species are endemic to American Samoa itself. Marine endemics have not been identified, but a thorough investigation has not been conducted.

Threatened or endangered species. Federally listed species here include humpback whales and the green and hawksbill sea turtles. Additional species 'of concern' in the Territory include the sheath-tailed bat, 3 birds (Spotless Crake, Friendly Ground Dove, Many-colored Fruit Dove), several land snails, and others.

Pests and weeds (invasive non-native species). There are many: rats, 3 bird species (2 mynas and bulbuls), feral pigs, dogs, cats, toads, house gecko, tilapia and molly fishes, African snails, about 250 alien species of vascular plants (many of them weed species), and others.

Dangerous species. Few. On land, no poisonous snakes, but a bite from a large 8-inch centipede can be painful. In the ocean, sharks are generally not a problem but stepping on the poisonous spine of a stonefish can be a serious medical emergency although this rarely happens. Consumers of fish should note that ciguatera poisoning has been found (infrequently) in several snappers (locally called mu) and a few other fish species. Also, avoid eating any fish or invertebrate caught in Pago Pago Harbor, because they are contaminated with heavy metals and other pollutants.

Tropical diseases. Malaria is not present, but two other mosquito-transmitted diseases can occur here: dengue fever (caused by a virus) and filariasis (elephantiasis, caused by a parasitic nematode worm). However, the chance of getting either by a visitor is slight.

P. Craig, NPS

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