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6 Enhancing Rural Farmer Income through Fish Production1076.3 Water Resources for Culture-Based Fisheries Developmentin Sri LankaAn estimated 12,000 village reservoirs, of which 10,000 are functional for irrigatingagricultural lands, are found in Sri Lanka (Anon 2000) . These small reservoirs,in addition to their primary uses, i.e., irrigation, are used for various communalactivities such as bathing, drinking-water supply, and buffalo and cattle keeping.CBF development in these water bodies should therefore be carried out withoutimpeding their multiple uses.Small-scale water conservation systems, referred to as village/small reservoirs,created by constructing earthen bunds across natural drainage basins, area distinctive feature of the low-rainfall zone of Sri Lanka. These reservoirsdepend entirely on direct rainfall and runoff water from their own catchments.These reservoirs, total an acreage of 39,300 ha (Mendis 1977 , Table 6.1 ). Theseoccur in the form of distinct cascades that are positioned as either well-definedsmall cascades or meso-catchment basins (Udawattage 1985 ; Panabokke 2001) .A cascade is defined as a connected series of tanks organized within the mesocatchmentsof the dry-zone landscape, storing, conveying, and utilizing waterfrom an ephemeral rivulet (Madduma Bandara 1985) . These reservoirs irrigatepaddy fields along the channels (Panabokke et al. 2002; Fig. 6.2 ) . A great majorityof these small village reservoirs are less than 100 ha in surface area at fullsupply level (FSL), and are distributed across the undulating landscape of thelow rainfall zone.The main source of livelihood of the majority of the people in the low-rainfall zoneis cultivation of crops (mainly paddy) and allied activities in the two agriculturalfarming seasons (“ Yala ” from March to June and “ Maha ” from October to February),based on the annual rainfall pattern. Hence, the majority of the people in the lowrainfallzone have two peak working seasons in a year. Between those two laborintensivepeak seasons, the farmers have sufficient time to be mobilized to CBFactivities (De Alwis 1983 ; Fernando and Halwart 2000 ; Murray et al. 2001) .6.4 CBF Development in Reservoirs of Sri LankaMost of the minor irrigation reservoirs in the low-rainfall zone of Sri Lanka are dryfor 2–3 months in August–October every year, and are therefore termed as seasonalreservoirs. Based on a survey carried out in 1962, Mendis (1965) suggested that thesmall, village reservoirs (minor irrigation reservoirs) are biologically productive,and could be used for enhancing fish production. Subsequently, in 1963, eight reservoirsin Polonnaruwa administrative district were stocked with juveniles ofChanos chanos and O. mossambicus (Anon 1964) . Indrasena (1964) also suggestedthat these reservoirs can and should be utilized for the development of CBF.Indrasena (1965) reported that high yields were obtained from several seasonal