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112 U.S. Amarasinghe and T.T.T. Nguyenabsence of monitoring by the centralized management unit (i.e., Inland FisheriesDivision of the Ministry of Fisheries) and the lack of a subsidized fingerling supplyfor stocking, CBF was not sustained.Under a project funded by the Australian Centre for International AgriculturalResearch (ACIAR), a research team from the University of Kelaniya and NAQDAof Sri Lanka, in collaboration with Deakin University, Australia, carried out anextensive study in 45 village reservoirs, focusing on developing holistic managementstrategies for CBF in village reservoirs incorporating biological, physical, andsocioeconomic factors.Carlson’s trophic state index (TSI) (Carlson 1977) measured on the basis of chlorophylla [TSI (Chl- a )], was used to classify the village reservoirs based on the biologicalproductivity. As TSI (Chl- a ) is positively correlated to CBF yield, it is useful forplanning CBF development strategies in village reservoirs of Sri Lanka (Jayasingheet al. 2005) . Reservoirs with similar trophic characteristics also showed significantcorrelation ( p < 0.05) between shoreline/area ratio and CBF yield (Jayasinghe et al.2006) . Also, Jayasinghe and Amarasinghe (2007) demonstrated a positive influence ofbuffalo density in the vicinity of reservoir on CBF yield. This was owing to the additionof nutrients through cow dung into the village reservoirs.Naturally recruiting fish species from the associated inlet waters, especially inthose village reservoirs that do not dry completely, also influence the performanceof stocked species in CBF. In reservoirs where naturally recruited predatory fishspecies such as Ophicephalus striatus and Mystus keletius occur in sufficient numbers,the CBF harvests of stocked species are low owing to their high mortalities(Wijenayake et al. 2005, 2007 ) . As density-dependent factors also influence theCBF yields, the optimal SD is found to be about 3,500 fingerlings per ha(Wijenayake et al. 2005, 2007 ) . It should be noted that the optimal SD in CBF isalso dependent on the biological productivity of the reservoirs.Being a communal activity, socioeconomic factors are also equally important forthe development of CBF in village reservoirs. It has been found that small groupsize and homogeneity with regard to caste, kinship, and political ideology of thefarming communities, and the level of education and good leadership qualities ofthe group members have positive influences on the attitudes of rural communitiestowards the uptake and development of CBF in village reservoirs (Kularatne et al.2008) .6.5.1 Marketing and Economics of CBFThe Kanna meeting (a community meeting held at the beginning of the croppingseason) of the FOs is a major event in the village. At this meeting, planning ofagricultural activities takes place, and collective decisions are made which cannotbe changed by the individuals until the end of the cultivation season, except underspecial circumstances. With the new provisions available for the development ofCBF in the Agrarian Development Act of 2000, important decisions on CBF