Header

Skip Navigation LinksReefBase > Global Database
          RSS Feed
Resources - Overview

Region     Country
Search Show Tips

Search Result: 6 records

1 . American Samoa     American Samoa
American Samoa is a U.S. Territory located approximately 4,200 km south of Hawai’i. It is the southernmost of all U.S. possessions and the only U.S. jurisdiction in the South Pacific. American Samoa comprises seven islands (five volcanic islands and two coral atolls) with a combined land area of approximately 200 km2 (Figure 11.1). The five volcanic islands, Tutuila, Aunu’u, Ofu, Olosega, and Ta’u, are the major inhabited islands of American Samoa. Tutuila, the largest island, is also the center of government and business. Ofu, Olosega, and Ta’u, collectively referred to as the Manu’a Islands, are 107 km east of Tutuila. Two outer islands, Rose Atoll and Swains Island, are approximately 259 km and 327 km from Tutuila, respectively. Rose Atoll is uninhabited and is managed as a National Wildlife Refuge (NWR) by the U.S. Fish and Wildlife Service (USFWS), while Swains Island is inhabited by a subsistence population of approximately 10 people.

The islands range in size from the populated high island of Tutuila (138 km2) to the uninhabited and remote Rose Atoll (4 km2). The total area of coral reefs (to the 100 m depth) in the Territory is 296 km2. Due to the steepness of the main islands, shallow water habitats around the islands are limited and consist primarily of fringing coral reefs (85% of total coral reef area) with a few offshore banks (12%) and two atolls (3%). The fringing reefs have narrow reef flats (50-500 m); depths of 1000 m are reached within 2-8 km from shore.

Coral reefs in American Samoa support a high diversity of Indo-Pacific corals (over 200 species), fishes (890 species), and countless invertebrates. In recent years the corals have demonstrated considerable resilience following a series of natural disturbances, including four hurricanes in the past 18 years, a devastating crownof- thorns starfish invasion in 1978, and several recent bleaching events. Following each disturbance, the corals eventually recovered and grew to maintain the structural elements of the reefs. However, because serious overfishing has occurred, the Territory’s coral reef ecosystem cannot be considered healthy based on the resilience of the corals alone. Furthermore, climate change impacts such as warm-water coral bleaching and coral disease are becoming increasingly apparent and pose a major, repetitive impact to the structure and function of local reefs. Additionally, the Territory’s high population growth rate (2.1% per year) continues to strain the environment with issues such as extensive coastal alterations, fishing pressure, loss of wetlands, soil erosion and coastal sedimentation, solid and hazardous waste disposal, and pollution.
Source: Craig, P., G. DiDonato, D. Fenner, and C. Hawkins , 2005 , The State of Coral Reef Ecosystems of American Samoa. . p.312-337 in Waddell, J. (ed.), 2005. The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2005. NOAA Technical Memorandum NOS NCCOS 11. NOAA/NCCOS Center for Coastal Monitoring and Assessment’s Biogeography Team. Silver Spring, MD. 522 pp. (See Document)

2 . American Samoa     American Samoa
Craig et al. (2000) suggested that American Samoa’s oceanic waters demonstrate excellent quality, and there are no indications that oceanic water quality has since changed. Furthermore, the water quality problems that emerged in Pago Pago Harbor during the 1970-80s have greatly improved, based on chl a, TN, and TP levels (Figure 11.9).

However, the picture is less clear in other coastal areas of the Territory, as there are very few data from the near coastal regions of American Samoa. This will soon be remedied, as the National Park of American Samoa and ASEPA recently finished a collaborative, comprehensive coastal water quality survey around Tutuila and the Manu’a Islands. This survey used a probabilistic design to sample the waters from the coastline to onequarter mile offshore. This study will provide the first Territory-wide data on water quality in the near coastal areas.
Source: Craig, P., G. DiDonato, D. Fenner, and C. Hawkins , 2005 , The State of Coral Reef Ecosystems of American Samoa. . p.312-337 in Waddell, J. (ed.), 2005. The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2005. NOAA Technical Memorandum NOS NCCOS 11. NOAA/NCCOS Center for Coastal Monitoring and Assessment’s Biogeography Team. Silver Spring, MD. 522 pp. (See Document)

3 . American Samoa     American Samoa
The status of coral reefs in American Samoa is mixed. There are notable improvements, but other serious problems persist. Generally, corals are in good condition, having recovered from massive cyclone damage in 1991. More recent but moderate damage occurred during Hurricane Heta in 2004, but given the observed resilience of corals in the Territory and the generally low level of anthropogenic stressors (e.g., low recreational use), regrowth is expected over the next several years. Another noteworthy improvement is the removal of 10 shipwrecks off local reefs. There has also been a marked improvement in water quality in Pago Pago Harbor.

Local reefs, however, have been seriously overfished and few large fish remain. Genuine consideration needs to be given to reducing overall catches and developing effective MPAs that provide long-term protection to harvested species. Despite the resiliency of corals mentioned above, scientists are observing increases in coral bleaching and mortality, as well as areas heavily impacted by coral diseases, which have historically been rare.
Source: Craig, P., G. DiDonato, D. Fenner, and C. Hawkins , 2005 , The State of Coral Reef Ecosystems of American Samoa. . p.312-337 in Waddell, J. (ed.), 2005. The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2005. NOAA Technical Memorandum NOS NCCOS 11. NOAA/NCCOS Center for Coastal Monitoring and Assessment’s Biogeography Team. Silver Spring, MD. 522 pp. (See Document)

4 . American Samoa     American Samoa
The Territory of American Samoa consists of 5 volcanic islands and 2 atolls in the central South Pacific Ocean. The islands are small, ranging in size from the heavily populated main island of Tutuila (142 km2 ) to the uninhabited and remote Rose Atoll (less than 1 km2 of land). The volcanic islands are surrounded by fringing reefs, while the atolls have steeply sloping sides, and Rose Atoll has a lagoon. More than 2,700 species of corals, fish, invertebrates, marine plants, turtles and marine mammals are known.
Source: Goldberg, J., K. Adams, J. Albert, J. Asher, P. Brown, V. Brown, D. Burdick, B. Carroll, P. Craig, D. Fenner, C. Fillmed, V. Fread, M. Gawel, A. George, Y. Golbuu, L. Goldman, C. Graham, A. Hall, M. Hasurmai, L. Jacob, D. Jacobson, E. Joseph, J. Kenyon, W. Kostka, T. Leberer, M. Luckymis, E. Lundblad, S. Malakai, J. Maragos, A. Marcus, S. Marino, D. Mathias, J. Mcilwain, J. Miller, D. Minton, M. Nadon, S. Palik, N. Pioppi, L. Raymundo, B. Richards, M. Sabater, R. Schroeder, P. Schupp, E. Smith, T. Zgliczynski and B. Zgliczynski , 2008 , Status of Coral Reef Resources in Micronesia and American Samoa: 2008 . In: Wilkinson, C. (ed.). Status of Coral Reefs of the World: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Center, Townsville, Australia. p199-212. (See Document)

5 . American Samoa     American Samoa
American Samoa consists of five main volcanic islands and two atolls, which are situated in the central tropical South Pacific (Figure 10.1) at approximately 14°S and 170°W. American Samoa is the only U.S. territory located south of the equator. It experiences seasons opposite to those in all other U.S. areas, and has atmospheric and oceanic circulation patterns found in the southern hemisphere. The five volcanic islands are part of a hotspot chain that also includes Upolu and Savaii, the two larger volcanic islands of (independent) Samoa to the west of American Samoa, several seamounts west of Samoa, ridges extending southeast from Tutuila and northwest from Ofu, and an active undersea volcano east of the island of Tau in American Samoa, named Vailuluu. American Samoa also includes two atolls, Swains and Rose, both of which are much older than the volcanic islands and not geologically related.



The American Samoa archipelago is composed of high volcanic islands and low-lying atolls that have narrow reef flats (50-500 m) and steep offshore banks dropping to oceanic depths within 0.5-8 km from shore. The shallow water habitats are composed primarily of fringing reefs, a few offshore banks, and the two atolls. The archipelago (Figure 10.2) lies within the South Equatorial Current, characterized by warm (28-30°C) westward flowing, oligotrophic surface waters, with a deep thermocline (approximately 120-200 m). Area winds are generally light and variable during the austral summer rainy season, except during cyclones, with consistently stronger trade winds from theeast-southeastd ominating in other seasons (Figure 10.3). All of the islands are seasonally impacted by episodic long period swell generated from the mid-latitude cyclone belts of both the northern and southern hemisphere (30-60° latitude) and more infrequently by large tropical cyclones, which have historically impacted the islands on 2-7 year timescales. These tropical cyclones and related storms may bring large swells, destructive winds and heavy rains.Spur and groove reef formations are fairly common on the reef slope. On Tututila, the reef slope descends to about 20-30 m where it reaches a rubble or sand covered shelf (Figure 10.4). The shelf extends for about 1-4 km and reaches about 100 m depth at its outer edge, ending in a near-vertical escarpment. The escarpment is composed of layers of limestone about 5-10 cm thick and extends down to at least 350 m, where a talus slope of calcareous sand and debris extends below 400 m depth (Wright, 2005).



Multibeam sonar surveys by the NOAA Pacific Islands Fishery Science Center, Coral Reef Ecosystem Division (PIFSC-CRED) team has revealed that the shelf around Tutuila has a number of banks on it, some of which form an interrupted chain resembling a drowned barrier reef, a term used for it as early as 1921 (Chamberlin, 1921;Davis, 1921). Taema Banks at the mouth of Pago Pago harbor and Nafanua Banks, which extends from Aunuu Island toward Taema Banks, are believed to be part of this drowned barrier reef. Although both banks have coral on their outer slope and a portion of their tops, the banks have not yet been explored.
Source: D. Fenner, M. Speicher, S. Gulick, G. Aeby. S.C. Aletto, P. Anderson, B. Carroll, E. DiDonato, G. DiDonato, V. Farmer, D. Fenner, J, Gove, S. Gulick, P. Houk, E. Lundblad, M. Nadon, F. Riolo, M. Sabater, R. Schroeder, E. Smith, M. Speicher, C. Tuitele, A. Tagarino, S. Vaitautolu, E. caoli, B. Vargas-Angel, P. Vroom, p. Brown, E. Buchan, A. Hall, J. Helyer, S. Heron, J. Kenyon, R. Oram, B. Richards, K.S. Saili, T. Work and B. Zgliczynski , 2008 , The State of Coral Reef Ecosystems of American Samoa. pp. 307-351 . In: J.E. Waddell and A.M. Clarke (eds.), The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2008. NOAA Technical Memorandum NOS NCCOS 73. NOAA/NCCOS Center for Coastal Monitoring and Assessment's Biogeography Team. Silver Spring, MD. 569 pp. (See Document)

6 . American Samoa     American Samoa
In October 2006, the American Samoa Coral Reef Advisory Group (CRAG) released an economic valuation of American Samoa’s coral reef resources, prepared by Jacobs, Inc. in association with MRAG Americas, the National Institution of Water and Atmospheric Research, and Professor N. Polunin.



As of 2004, the coral reefs of American Samoa provide benefits on the order of $5.1 million/year, and the territory’s mangroves add an additional $0.75 million/year. Together, these critical natural resources account for 1.2% of the American Samoa GDP. A few of the most important benefits provided by coral reefs include: $689,000/year benefit due to coral
reef fisheries; $73,000/year benefit resulting from recreational uses; $70,000/year benefit deriving from bottom fishing; $447,000/year benefit relating to shoreline protection provided by the reefs. These are just some of the benefits, economic and otherwise, American Samoa stands to lose without continued efforts to increase our understanding of and protect these fragile ecosystems. In addition to the above, a gain of $2,753,000/year in direct benefits could be realized through the complete and effective implementation of proposed mitigation and enhancement measures, as well as management initiatives such as strengthening fisheries regulations and controlling coastal development.
Source: D. Fenner, M. Speicher, S. Gulick, G. Aeby. S.C. Aletto, P. Anderson, B. Carroll, E. DiDonato, G. DiDonato, V. Farmer, D. Fenner, J, Gove, S. Gulick, P. Houk, E. Lundblad, M. Nadon, F. Riolo, M. Sabater, R. Schroeder, E. Smith, M. Speicher, C. Tuitele, A. Tagarino, S. Vaitautolu, E. caoli, B. Vargas-Angel, P. Vroom, p. Brown, E. Buchan, A. Hall, J. Helyer, S. Heron, J. Kenyon, R. Oram, B. Richards, K.S. Saili, T. Work and B. Zgliczynski , 2008 , The State of Coral Reef Ecosystems of American Samoa. pp. 307-351 . In: J.E. Waddell and A.M. Clarke (eds.), The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States: 2008. NOAA Technical Memorandum NOS NCCOS 73. NOAA/NCCOS Center for Coastal Monitoring and Assessment's Biogeography Team. Silver Spring, MD. 569 pp. (See Document)

Side Bar