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Article Excerpt
Introduction
Despite extremely high rates of primary production in coral reef ecosystems, actual yield of coral reef fisheries is relatively low. In addition, the ecological complexity, richness, and specialized life histories of coral reef organisms and communities make them particularly susceptible to overexploitation (Birkeland, 1997). Results of such overexploitation in Caribbean islands are seen in the documented drastic declines in catch-per-unit-effort, size structure, and/or species shifts in the fisheries of Jamaica, Grenada, the U.S. Virgin Islands, and others (Koslow et al., 1988; Jeffery, 2000; Rogers and Beets, 2001). Indeed, subsistence fishing to support a single family has been described as impacting target populations on the scale of a whole bay in the U.S. Virgin Islands (Coblentz, 1997).
Navassa Island is small and, although claimed by the United States as part of the Caribbean Islands National Wildlife Refuge, sovereignty is disputed by Haiti. Due to its isolation, uninhabited status (except for temporary squatters), and some preliminary quantitative visual fish census work, Navassa Island has been described as displaying a relatively pristine reef community (Anonymous, 2000; Grace et al., 2000; Miller and Gerstner, 2002). However, this interpretation has also been questioned due to the observation of ongoing fishing activity by migrant Haitians, the complete lack of quantitative information regarding the intensity of this fishing activity, and the potential for its rapid escalation (Collette et al., 2003: Grace et al., 2000; Miller and Gerstner, 2002)
Navassa Island is about 5 [km.sup.2] in area and is comprised of a raised plateau surrounded by cliffs which reach down to a submarine terrace at 23-30 m depth (Fig. 1). The primary fishery habitats are reef walls formed by the cliffs and large boulders (or "calves" as analogous to the chunks that fall off of icebergs) that have been dislodged from the cliffs, scattered patch reefs and hardbottom areas on the 25-30 m terrace, and deeper reef slopes and shelves (>30 m) farther offshore that have not been well described.
[FIGURE 1 OMITTED]
Navassa Island's oceanic position in the Windward Passage (Fig. 1) exposes it to substantial physical energy. The east coast, particularly, bears the brunt of persistent swells, regular storms, and hurricanes. Inshore and backreef habitats, which are important in the life history of several reef fish groups, are largely absent.
Despite its status as a National Wildlife Refuge, fisheries at Navassa Island are effectively unmanaged as regulations are not well publicized and enforcement is non-existent due to Navassa's remote location, surrounded by international jurisdictions. Fishing activities are undertaken by migrant Haitian artisanal fishermen, and these activities appear to have been ongoing since at least the 1970's. Anecdotal observations from a previous NMFS expedition (1) reported five Haitians fishing out of a 4.3 m sailboat along the north/northwest coast and "catching only small grunts [Haemulidae] and one small barracuda [Sphyraena barracuda]". Other anecdotal accounts suggest that some technological escalation in this fishery had occurred between scientific expeditions which had occurred in 1997 and 2000. That is, no motors were observed in 1997, while all...
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