U.S. Coral Reef Task Force

A healthy colorful reef

American Samoa

Map of American Samoa

American Samoa is an unincorporated U.S. territory in the South Pacific. It consists of 5 islands and 2 atolls: Tutuila, Aunu’u, Manua islands (Taʻū, Ofu and Olosega), Swains Atoll, and Rose Atoll. The islands form a combined landmass area of 86 mi2 (224 km2) [1]

The waters of American Samoa host 114 mi2 (296 km2) of reef, in which 85% are fringing reefs, 12% are offshore banks, and 3% are atolls. [2]

American Samoa’s Reefs are Home To:

200 Coral Species

890 Fish Species

[2]

School of fish swimming over a reef

Reef Threats

Water Quality Icon
Unsustainable fishing icon
Environmental change icon

Poor Water Quality

Unsustainable Fishing

Environmental Change

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  • In American Samoa, researchers found a direct correlation between land-based pollution and the health of reefs downstream [3]
  • The main inhabited island of Tutuila has steep volcanic slopes, which are easily eroded by heavy rains. This sediment erosion, combined with pesticides and other pollutants from coastal developments, flows directly onto the reef and causes poor water quality. [4]
  • The Tafuna-Leone Plain on Tutuila is also very porous and collects groundwater that can flow onto the reefs. This groundwater is mostly polluted by agricultural chemicals, waste from pig farms, and on-site disposal systems like septic tanks. [4]
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  • Reef fish stocks in American Samoa have declined over the years, and sharks and large reef fish have seen especially large declines. [4]
    • In fact, current shark populations in American Samoa are expected to be only 4-8% the size of historical shark populations. [5]
  • During the 1990s, SCUBA spearfishing became very popular but resulted in severe depletion of fish stocks. This led to a ban on SCUBA spearfishing in 2000.
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  • Due to the island’s culture, geographical characteristics, and dependence on natural resources, American Samoa is vulnerable to the effects of global environmental change, such as increasing sea surface temperatures, ocean acidification, rising sea levels, intensifying storms, and changing rainfall patterns. [4]
  • Mass coral bleaching events have occurred in American Samoa in 1994, 2002, 2003, 2015, and 2017, all of which coincided with unseasonably warm sea surface temperatures. [4]

Reef Protections

American Samoa has several marine protected (MPAs) to manage and enhance coral reef fish populations. More specifically, American Samoa has 14 territory MPAs and 5 federal MPAs. Some of the MPAs prohibit any take of marine resources, while others allow subsistence fishing.  [7]

There is even one privately managed MPA: Alega Marine Sanctuary, which was founded in 1980 by two individuals and the village of Alega in order to heal and conserve the bay for future generations. [6]

Small blue fish swimming around a vibrant reef

Bright Spots and On-Going Initiatives

Snorkelers performing work on a reef

American Samoa has begun conducting coral reef restoration in recent years to restore and bolster the health of the island’s shallow coral reef ecosystems.

Agencies affiliated with American Samoa’s Coral Reef Advisory Group (CRAG) initiated the island’s first coral restoration pilot project in the village of Aua in 2021.

Vibrant underwater reef scene

Fagatele Bay in the National Marine Sanctuary of American Samoa is a success story that demonstrates a local reef’s ability to bounce back from significant threats. Scientists first started surveying coral cover and other reef-health indicators in 1985 after the reef was decimated by a Crown-of-Thorns Sea Star (COTS) outbreak in 1979. Surveys continued to be conducted every few years through 2018. In the most recent survey in 2024, researchers found the coral reef to be the healthiest it had ever been, showing a complete recovery despite severe weather events and other disturbances that threatened the reef in the years since the first survey. [8]

American Samoa Coral Reef Advisory Group (CRAG) Logo

The reefs of American Samoa are managed by the Coral Reef Advisory Group (CRAG), which is an intergovernmental organization consisting of local and federal agencies.

CRAG agencies include: the Department of Marine and Wildlife Resources (DMWR), the Department of Commerce (DOC; including AS Coastal Zone Management program [ASDOC-CZM]), the American Samoa Environmental Protection Agency (AS-EPA), and the American Samoa Community College (ASCC). CRAG also has voluntary participation from National Park Service of American Samoa (NPSA), the National Ocean and Atmospheric Administration (NOAA)’s National Marine Sanctuary of American Samoa (NMSAS) and the US Fish and Wildlife Service (FWS).

Check out the CRAG website to learn more about their work!

Connect with CRAG on social media @coralreefadvisorygroup

photo taken from underwater showing the turbulence of waves crashing above a reef
Reef showing a large coral head and numerous branching corals
Large school of fish swimming on a reef
Reef scene
Photo taken from below showing the sun shining through the water on a reef

Other resources to explore

Sources cited