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The Central West Pacific Islands consists of large number of islands and groups of islands extending from Palau to Tuvalu which are interconnected by a large marine ecosystem. This large body of warm water is bounded by cold water upwelling to the east. The surface temperatures can be as high as 83 degrees Fahrenheit varying little to a depth of 100-150m. There is a well defined salinity front at the boundary of cold water, with low salinity in the warm region. The region has low primary productivity compared to the cold neighboring water; however, surface currents carry some of the cold water west resulting in high secondary productivity. This secondary productivity supports a large pelagic community, including tuna, billfish, and sharks. The warm water of the Central West Pacific also has a significant impact on global weather patterns during El Nino events, during which the warm surface water of the central west Pacific is able to flow eastward due to weaker east to west trade winds. This results in higher sea surface temperatures off of South America and widespread changes in weather.

The West Central Pacific region contains a variety of special marine features including coral reefs, seamounts, and deep sea trenches, some of which are yet to be explored. These features provide habitat for a large variety of marine species. The region also encompasses many islands, therefore, consisting of an abundance of coastal area and a widespread dependence on marine resources. Tuna is by far the most important marine resource for the people who live on these islands. The majority of the tuna caught in the north and central Pacific Ocean is from the Central West region. Other commercially exploited species include mahi mahi, wahoo, striped marlin, swordfish, and blue sharks. Some species, such as trochus, green snail, and pearl oysters are commercially attractive due to their beauty and are use to make jewelry and buttons. Bêche de mer, or sea cucumbers, are commonly collected for consumption in the South Pacific. They are also a highly valued food item in Asia. Culturally, marine mammals, seabirds, and sea turtles are important, because they are well recognized symbols of the area. Of the many species of whale found in the area, at least 5 are considered endangered: blue, humpback, sei, sperm, and fin. Five species of sea turtle nest, feed, and migrate in the region. Three of which-loggerhead, hawksbill, and green-are most abundant in the Central West Pacific compared to other locations in the world.

Although the Central West Pacific Island region is extensive and includes many island countries, the threats to the marine ecosystem are common to all. Management of these threats is a challenge due to the number of countries involved, the dependence of communities on the resources, and the fact that there are areas of high seas to contend with.

Common threats to the marine system include unsustainable harvesting, pollution, illegal and unregulated fishing, and habitat degradation. Unsustainable harvesting is not limited to fisheries such as albacore and yellowfin tuna. It also extends to dugongs and sea turtles, which are hunted locally and are threatened by better technology and an increase in human population. Pollution of the ecosystem occurs from waste and general contamination from shipping and fishing vessels. Run off of sewage can adversely affect near shore species and degrade habitat. Pollution from the introduction of persistent organic chemicals which originate from industrialized countries far away but are deposited in the local region is also a concern. Illegal, unregulated, and unreported fishing is a major threat to transboundary fish stocks and non-target species. Tuna fishing on the high seas is not regulated, and marine resource extraction by locals is poorly regulated and a low priority due to the dependence on those resources for subsistence. While driftnet use has been made illegal, fishing using this method still occurs and continues to impact seabird populations, marine mammals, and juvenile fish species.

Though threats to the marine ecosystem do exist, attempts are being made to decrease transboundary issues and increase awareness in the local communities, so that sustainable practices and ecosystem based management can be put into practice. It has been agreed upon by many of the countries in the region that conservation of marine resources and protection of biodiversity will benefit everyone.

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