For example, most species of Caribbean groupers are protogynous hermaphrodites that form size-structured spawning aggregations comprised of small females and large terminal-phase males ( Domeier & Colin 1997). The life-history characteristics of groupers forming spawning aggregations render them particularly vulnerable to even moderate fishing mortality. However, well-placed MPAs can protect particularly vulnerable periods during a species life history such as temporary residence in nursery, feeding and spawning habitats ( Kramer & Chapman 1999). beyond the area immediately adjacent to reserve boundaries) and have a limited ability to permanently protect populations such as groupers and snappers that engage in long-distance migrations ( McClanahan & Kaunda-Arara 1996, Bohnsack 1998, McClanahan & Mangi 2000, Roberts et al. Although these reviews showed the positive effects of MPA’s on various biological measures inside reserves, most existing reserves may be too small to benefit regional fisheries (i.e. Most MPAs, regardless of size, seem to have a relatively rapid (1 to 3 yr) and positive effect on the density, biomass, size and diversity of organisms within the closed area compared to outside or after reserve formation versus before ( Halpern & Warner 2002, review). Marine protected areas (MPAs), which prohibit all fishing activity, are beginning to be recognized as alternative marine conservation management tools implemented to attain sustainable fish populations by maintaining ecosystem biodiversity, conserving genetic diversity, enhancing spawning stock, increasing productivity and reproductive output and protecting habitat structure (reviews by Allison et al. Where once snappers and groupers made up the bulk of the catch of the commercial fishery, landings throughout the Caribbean are now dominated by herbivorous species such as parrot fishes and surgeon fishes ( Tobias 1997). Since spawning aggregations are the primary source of larval production and may replenish the local fishery through larval retention and recruitment ( Roberts 1996, Sadovy 1996), overfishing of spawning aggregations may dramatically reduce the local abundance of these species causing population-level impacts ( Claro & Lindeman 2003). 1987, Beets & Friedlander 1992, Sadovy et al. These effects are accelerated when fishers target the large, annual spawning aggregations formed at predictable locations by many species of tropical reef fishes, especially snappers and groupers ( Johannes 1978, 1989, Olsen & LaPlace 1978, Colin et al. Sustained fishing pressure in multi-species tropical fisheries can cause progressive changes in fish communities as well as shifts in the size structure of targeted populations ( Munro 1996). Over the past 20 yr, many island nations throughout the Caribbean, including the United States Virgin Islands (USVI), have witnessed steady declines in catches of commercially important marine fishes ( Council 1985, Roberts 1997). Protection of the spawning aggregation site may have also contributed to an overall increase in the size of red hind caught in the commercial fishery, thus increasing the value of the grouper fishery for local fishermen. Information from tag returns indicated that red hind departed the protected area following spawning and migrated 6 to 33 km to a ca. Average density and biomass of spawning red hind increased by over 60% following permanent closure whereas maximum spawning density more than doubled. Compared with studies conducted before the permanent closure, the average size of red hind increased mostly during the seasonal closure period (10 cm over 12 yr), but the maximum total length of male red hind increased by nearly 7 cm following permanent closure. Tag-and-release fishing and fish transects were used to evaluate population characteristics and habitat utilization patterns of a red hind spawning aggregation between 19. This study provides some of the first information on the population response of a spawning aggregation located within a marine protected area. Thomas, United States Virgin Islands, was closed seasonally in 1990 and closed permanently in 1999 to protect an important red hind Epinephelus guttatus spawning site. The Red Hind Bank Marine Conservation District located in St. Spawning aggregations are often targeted by local fishermen, making them extremely vulnerable to over fishing. Many species of groupers form spawning aggregations, dramatic events where 100s to 1000s of individuals gather annually at specific locations for reproduction.
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