Productivity enhancement through enclosure culture in a sub-tropical wetland of Bundelkhand region, India

The enclosure culture i.e. pen culture forin situ raising of stocking material was demonstrated in the Loni wetland, a sub-tropical wetland of Bundelkhand region in central India. Pen stocked with 20000 fry of Indian major carps (IMCs), catla, rohu and mrigal in the ratio 1:2:1 with initial weight 2.1, 2.83 and 2.82 g respectively @20 m(2). The experiment was conducted during September 2018 to November 2018 for two months. Catla, rohu and mrigal exhibited substantial difference (p<0.05) in the growth pattern during the study with catla growing from 2.1 +/- 0.21 to 24.25 +/- 2.12 g, rohu from 2.83 +/- 0.25 to 19.58 +/- 1.81g whereas mrigal from 2.82 +/- 0.23 to 15.42 +/- 1.10 g. The specific growth rate (SGR) recorded was 124.6, 108.9 and 82.43% in catla, rohu and mrigal, respectively. The survival rate was maximum in rohu (76%), followed by catla (68%) and mrigal (42%). The benefit to cost ratio (BCR) estimated was 1.69 and proportion of return on investment was 0.69. Through this intervention, the productivity of fish yield reached up to 450 kg ha(-1) yr(-1) from 165 kg ha(-1) yr(-1) which can be further increased manifolds. Based on the results of the present experiment, it can be suggested that rearing of IMC fry to fingerlings in pen enclosures in wetlands is technically feasible and economically viable.