Hawaii FEP - Western Pacific Fishery Council

CHAPTER 3: DESCRIPTION OF THE ENVIRONMENT3.1 IntroductionChapter 3 describes the environment and resources included within the Hawaii Archipelago FEP.For more information, please see the Council’s FMP, FMP amendments and associated annualreports. Additional information is available 2 in a 2008 environmental assessment for theCrustaceans FMP (WPRFMC 2008a), a 2001 Final EIS for the Coral Reef Ecosystems FMP(WPRFMC 2001a), 2007 and 2008 environmental assessments for the Precious Corals FMP(WPRFMC 2007b, WPRFMC 2008b), a 2005 Final EIS to the Bottomfish FMP (WPRFMC2005b), and a 2007 Final Supplemental EIS to the Bottomfish FMP (WPRFMC 2007a) whichare incorporated here by reference. Although this FEP will not manage the Western PacificRegion’s pelagic resources, successful ecosystem-based management requires consideration ofinteractions between the pelagic and demersal environments at an ecosystem level, and thus bothare discussed here. Similarly, although this FEP will apply only to Federal waters around theHawaii Archipelago, the environment and resources of nearshore (i.e., State of Hawaii) watersare also discussed so as to provide an overview of the area’s entire demersal ecosystem.3.2 Physical EnvironmentThe following discussion presents a broad summary of the physical environment of the PacificOcean. The dynamics of the Pacific Ocean’s physical environment have direct and indirecteffects on the occurrence and distribution of life in marine ecosystems.3.2.1 The Pacific OceanThe Pacific Ocean is world’s largest body of water. Named by Ferdinand Magellan as MarePacificum (Latin for “peaceful sea”), the Pacific Ocean covers more than one third of Earth’ssurface (~64 million square miles). From north to south, it’s more than 9,000 miles long; fromeast to west, the Pacific Ocean is nearly 12,000 miles wide (on the Equator). The Pacific Oceancontains several large seas along its western margin including the South China Sea, Celebes Sea,Coral Sea, and Tasman Sea.3.2.2 Geology and TopographyPacific islands have been formed by geologic processes associated with plate tectonics,volcanism, and reef accretion. The theory of plate tectonics provides that Earth’s outer shell, the“lithosphere”, is constructed of more than a dozen large solid “plates” that migrate across theplanet surface over time and interact at their edges. The plates sit above a solid rocky mantle thatis hot, and capable of flow. Figure 3 is a schematic diagram of Earth’s lithospheric plates. Theseare made of various kinds of rock with different densities and can be thought of as pieces of agiant jigsaw puzzle–where the movement of one plate affects the position of others. Generally,the oceanic portion of plates is composed of basalt enriched with iron and magnesium which is2 Available from the Council at www.wpcouncil.org or at 1164 Bishop St. Ste 1400, Honolulu, HI 96813.35