Production trends and technical efficiencies of culture-based fisheries in five tropical irrigation reservoirs: A case study from Sri Lanka

Culture-based fisheries (CBF) are increasingly accepted as strategies for enhancing inland fisheries, especially in tropical Asia. In Sri Lanka, CBF development in irrigation reservoirs has gained momentum due to concerted efforts of government fisheries authorities for inland fisheries enhancement. In the present study, production trends of five irrigation reservoirs of Sri Lanka before and after the introduction of CBF were investigated and apparently optimal CBF yields were not realised. Hence, the stochastic frontier production function (SFPF) was employed to quantify technical efficiencies (TE) of CBF. For each reservoir, annual averages of input data from 2005 to 2018 (14 years) were used in the TE analysis. Hence, total sample size for estimation of SFPF was 70. Although CBF production gradually increased in all five reservoirs from 2005 to 2018, there were substantial variations of total fish production across the reservoirs. The SFPF indicated that CBF production could be further increased through more efficient management of inputs (i.e. number of fishers, mean number of fishing days per year and stocking density).