Integration of Aquaculture within Irrigation Systems: a poverty-focused approach

The potential for aquaculture to be integrated within a large-scale irrigation system taking a poverty-focused approach was investigated in the Mahaweli System H irrigation system of North Western Province, Sri Lanka. Using a livelihoods approach an initial situation appraisal identified the potential for aquaculture to be integrated within existing livelihoods activities. The appraisal revealed that decreasing returns from farming and fishing seasonality were major sources of household vulnerability. Using fish caught from the tank fishery, small-scale cage-based fattening of tilapia was developed with participants in an attempt to mitigate seasonal vulnerability caused by fishing seasonality. Participatory technology development was conducted with members of two communities within Mahaweli System H. Upon identifying resources and formulating a research agenda with participants, pilot trials were conducted by fisher-farmers in USG village and by a group of female cage operators in RAJ village. The study identified several constraints to sustainability of the culture system such as variable and low availability of small tilapia with which to stock cages, poor feed quality and latterly, competition for feed inputs. Despite their initial enthusiasm, women were particularly disadvantaged in this process as they were unable to catch their own fish with which to stock their cages and became dependent on men to assist them. The study showed that the cage-based fattening system was able to help meet emergency household expenses, although it was not efficient enough nor practiced on a large enough scale to contribute greatly to household security. In this manner, holding and fattening smaller tilapia is comparable with livestock holdings. Further development of cage design and feed administration improvements are needed to reduce production costs and improve the economic viability of the system