Renewed Justification for the Promotion of Carp Aquaculture in Seasonal Minor Irrigation tanks in Sri Lanka
S. CREECH, L. DASANAYAKE and J. WIJESINGHE
New data reaffirms the ability of carp to effectively utilize the naturally high productivity of seasonal minor irrigation tanks in Sri Lanka. Stocked fish attained average weights ranging from 0.98 kg to 2.3 kg. Productivity ranged from 8 to 675 kg ha-1 using stocking densities of less than 1000 fingerlings ha-1. Fish were sold in the village locally and nationally negating concerns about consumer preference for carps and their marketability. Aquaculture management committees (AMC) were formed, four of which successfully negotiated their social right to manage and harvest fish. It is recommended that an AMC obtains an aquaculture management license to consolidate this negotiated agreement. Economic analyses indicate that carp aquaculture in seasonal tanks with a water spread area (WSA) less than 3 ha is not economically viable. Arguments are advanced to suggest that carp aquaculture in seasonal tanks with a WSA less than 4 is unlikely to be socially sustainable. No evidence is found to suggest that the same constraints do not apply equally or more so to the culture of tilapia in seasonal tanks. It is argued that the recent a priori claims made for the culture of tilapia require substantiation in contrast to the promotion of carp aquaculture in seasonal tanks.