Hawaii FEP - Western Pacific Fishery Council

Currently, there are minimal harvests of precious corals in the Western Pacific Region. However,in the 1970s to early 1990s both deep- and shallow-water precious corals were targeted in EEZwaters around Hawaii. The commonly harvested precious corals include pink coral (Coralliumsecundum, Corallium regale, Corallium laauense), gold coral (Narella spp., Gerardia spp.,Calyptrophora spp.), bamboo coral (Lepidisis olapa, Acanella spp.), and black coral (Antipathesdichotoma, Antipathes grandis, Antipathes ulex).In general, western Pacific precious corals share several ecological characteristics: they lacksymbiotic algae in tissues (they are ahermatypic), and most are found in deep water below theeuphotic zone; they are filter feeders; and many are fan shaped to maximize contact surfaceswith particles or microplankton in the water column. Because precious corals are filter feeders,most species thrive in areas swept by strong-to-moderate currents (Grigg 1993). Althoughprecious corals are known to grow on a variety of hard substrate, they are most abundant onsubstrates of shell sandstone, limestone, or basaltic rock with a limestone veneer.All precious corals are slow growing and are characterized by low rates of mortality andrecruitment. Natural populations are relatively stable, and a wide range of age classes isgenerally present. This life history pattern (longevity and many year classes) has two importantconsequences with respect to exploitation. First, the response of the population to exploitation isdrawn out over many years. Second, because of the great longevity of individuals and theassociated slow rates of turnover in the populations, a long period of reduced fishing effort isrequired to restore the ability of the stock to produce at the MSY if a stock has been overexploited for several years.Because of the great depths at which they live, precious corals may be insulated from someshort-term changes in the physical environment; however, not much is known regarding thelong-term effects of changes in environmental conditions, such as water temperature or currentvelocity, on the reproduction, growth, or other life history characteristics of the precious corals(Grigg 1993).3.3.3 Pelagic EnvironmentConnectivity of the different marine environments mandates the importance each has on theothers with regards to species diversity and abundance, reproduction, sustainable harvest, habitatneeds, and trophic connections. The pelagic or open ocean ecosystem is very large comparedwith any other marine ecosystem; however, other oceanic communities are vitally important topelagic species in part because of the food-poor nature of much of the pelagic environment. Forexample, the mesopelagic boundary area described as being between 200 and 1,000 m depth andbordered by the photic zone above, and the aphotic zone below, provides habitat for a uniquecommunity of fishes, crustaceans, mollusks and other invertebrates which become prey for tunasand other pelagic species. Acoustic sampling studies off the coasts of Oahu and Kona wereimplemented by Benoit-Bird et al. (2001) to assess the spatial heterogeneity, horizontal andvertical migration patterns, relative abundances, and temporal patterns of the mesopelagiccommunity as well as the linkages among this community, the influence of the coastlines, andoceanographic parameters. The Benoit-Bird et al. study showed that the horizontal component of67