![]() ![]() ![]() Collectors were deployed on seven occasions between January 1994 and July 1996. These sites spanned over 500 km of Solomon Islands Ž Fig. To quantify spatial and temporal variation in abundance of spat in Solomon Islands, and to test a variety of different collectors, we sampled 24 sites from seven regions. We conclude by identifying the factors that have to be considered further before the economic viability of farming blacklip pearl oysters in the central-western Pacific can be evaluated. In particular, we focus on the apparent characteristics of good sites for the collection of spat, the time of year when spat are most abundant, the suitability of different systems for collecting spat and the apparent effect of predation on the abundance of spat. In this paper, we report results from a 2-year sampling program to assess spatial and temporal variation in abundances of spat in Solomon Islands. Third, blacklip pearl oysters from sheltered locations in the central- western Pacific have faster growth rates than those from eastern Polynesia Ž Friedman et al., 1996. Second, methods for collecting spat and growing blacklip pearl oysters are relatively simple. were exported annually from Solomon Islands until the end of 1993, when a moratorium on export of wild-caught pearl-shell was introduced Ž Richards et al., 1994. First, reasonable populations of blacklip pearl oysters still occur in some countries for example, about 25 tons Ž f 100,000 shells. Despite these differences, there are at least three reasons to explore the potential for culturing pearl oysters in the central-western Pacific. As a result of the more ‘open’ layout of reefs in the central-western Pacific, there are fewer obvious places where the spat of blacklip pearl oysters may accumulate. margaritifera, which are planktonic for ) 20 days Ž Southgate and Beer, 1996. , and there is no guarantee that larvae will be retained in the vicinity of natal reefs. Water movements are inherently less predictable Ž Andrews and Pickard, 1990. In general, reefs in the central-western Pacific have a more ‘open’ structure, with numerous passages linking patch, fringing and barrier reefs with deep-water. In the central-western Pacific, most reefs fringe high islands or occur in shallow, sub-littoral areas Ž Wells, 1988. However, there are major differences in the structure of reefs in the central-western Pacific compared to those in French Polynesia and Cook Islands Ž Wells, 1988. are particularly eager to assess their potential for farming black pearls. Several of the high-island nations of the central–western Pacific Ž Fiji, Vanuatu, Solomon Islands and Papua New Guinea. ![]() margaritifera is also distributed throughout much of the tropical Pacific Ž Sarver and Sims, 1996. Although the industry is confined mainly to lagoons in eastern Polynesia, P. The spat are then grown-out to a size suitable for the implantation of nuclei for the culture of pearls. of blacklip pearl oysters in such lagoons Ž Coeroli et al., 1984. Pearl oyster farmers in French Polynesia and Cook Islands capitalise on this situation by placing collectors for the spat Ž plantigrade larvae. When pearl oysters spawn within these habitats, the pelagic larvae are ‘trapped’ within the ‘enclosed’ lagoon Ž Richard, 1985. These atolls are favourable for the collection of juveniles because they have large lagoons, with limited exchange of water to the open ocean Ž Gabrie and Salvat, 1985. In French Polynesia and Cook Islands, a proportion of coral atolls are rich sources of juvenile P. and incur low transport costs Ž Sims, 1993. ![]()
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