World Aquaculture 33 the seven-month dry season (Figure 8). Pilot experiments are underway to incorporate simple aquaculture methods into the daily work activity of women engaged in oyster harvesting. During the early part of the oyster harvesting season, larger oysters of marketable size are mixed among smaller oysters that are typically discarded during the oyster harvest. Rather than simply discarding the juvenile oysters as wasted bycatch, fishers are encouraged to place smaller oysters into a floating basket cage constructed of locally available materials (Figure 9). The study will evaluate if culled oysters will grow to market size in floating gear and if the practice is economically feasible given the relatively low prices of oysters. Aquaculture might provide a more convenient supply of oysters as the season progresses because oyster harvesters are normally forced to travel farther as nearby market-sized oysters become locally depleted. Other pilot experiments are underway to incorporate simple aquaculture methods into the daily routines of women who fish for cockles following some of the procedures long used to grow blood ark clams Anadara granosa in Malaysia (Tookwinas 1983, Broom 1985). Cockle harvesters in the village of Kartong on the southern border of Gambia near southern Senegal have selected an intertidal sand flat, prepared the site by raking to remove predators, and seeded the flat (10 cockles/m2) with small (<10 cm) Senilia senilis seed from adjacent seed beds in the Kartong Estuary (Figure 10). Information on growth and post-transplant mortality is being collected by the fishers and a U.S. Peace Corps volunteer assigned Fig. 9. Gambian oyster fishers deploying experimental oyster culture float near their preferred fishing grounds at Kubuneh, Gambia. Photo by Emily Nichols. Conclusion Aquaculture in Gambia is very much in its infant stage, but it holds great promise because the Gambian people value seafood in their diets and there appears to be general support by both the government and the public for fish and shellfish farming. Major constraints to aquaculture in Gambia appear to be scarce and expensive access to capital, relatively poor transportation and shipping infrastructure in the country and in the case of shellfish, relatively low market prices that make gear acquisition relatively expensive in relationship to the value of the cultured crop. The forms of artisanal aquaculture that appear to hold the most promise for the country are those that can be incorporated into the regular routines of existing rice farmers, in the case of aquaculture of tilapia and other freshwater fish, or the routines of existing shellfishers, in the case of oysters and cockles. Although aquaculture is considered favorably by the Gambian government for its potential to build a Gambian export trade portfolio, the history of the faltering shrimp aquaculture in the country over almost three decades suggests that a number of barriers to business success remain in place. Notes Department of Fisheries, Animal & Veterinary Science, University of Rhode Island, Kingston, RI 02881 USA 2Department of Fisheries, Republic of The Gambia, 6 Marina Parade, Banjul, The Gambia. 3Ba-Nafaa Project, World Wide Fund, GIPFZA House, Kairaba Avenue, Fajara, The Gambia 4Based upon an unpublished 1981 manuscript “Fish Culture in the Gambia: Assessment of Problems and a Project Proposal” by Daniel Theisen, Crane Fig. 10. Woman clam farmer of Kartong with juvenile blood ark clams Senelia senilis to be seeded into prepared intertidal aquaculture plot. Photo by Casey Donohue. to assist the women with the project. The cockle-harvesting women of Kartong have noticed that that seed densities for S. senilis are very high in the estuary and there is considerable mortality of seed before they reach about 10 cm in shell length, presumably caused by crowding. (Continued on page 71)
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