Periphyton is the complex of sessile aquatic biota with associated detritus, attached to submerged substrates. A possibility of regular income generation through traditional farming is limited due to small land holding, soil salinity, frequent attacks of cyclones like ‘Aila’, floods, seawater inundation, agricultural practices without scientific knowledge and crop failures due to pests and diseases. The area is exposed to harsh agro-climatic situations leading to frustration, abandoning farming, migration of farming communities seeking better livelihood opportunities, shift to alternate income earning opportunities etc. In this backdrop, ‘different approaches in fisheries modules are envisaged as an effective tool to create examples before the farmers so that they become able to tap their own resources for sustainable income generation and to enhance their livelihood security. The units may be of different types depending on the resources and capacity of the farmers. Considering superior periphyton growth on bamboo was used as the substrate. This material is too expensive in South-Asia for resource-poor farmers. Therefore, cheap alternatives for the bamboo substrate have opted like nylon nets. 37 species were identified from the periphyton patches and it showed that the water temperature also less fluctuating in periphyton cultured based ponds compared to the farmers’ practice. The present study was mainly emphasis on tilapia culture at Sundarban water. Rearing management systems assessed were: fertilization alone (FA), combined fertilization-feeding (FF), fertilization periphyton (FP) and fertilization-compost application (FC) in triplicate ponds. Soaked mustard cake was used as a fertilizer @ 100 kg ha-1 at 15-day intervals in all the treatment ponds. Formulated crumble diet containing 29.7 per cent protein and 4.9 per cent lipid was used as a supplementary feed in FF. Bamboo poles were used as substrates (equivalent to 10% of pond surface area) to facilitate periphyton growth in FP and composted aquatic weed was applied @ 500 kg ha-1 in FC at monthly intervals. Ponds were stocked with grey mullet fry (3.36 ± 0.32 g/ 63.70 ± 4.61 mm) at 30,000 number ha-1.Cost of cultivation was found to be significantly reduced in the case of periphyton technology and this reduction was 31.25 per cent to 37.09 per cent higher in comparison to the fertilizer and feed. The net return of periphyton technology was found to be 45 per cent to 58 per cent higher than fertilizer alone experiments.

Keyword: Periphyton; Tilapia; Climate change; Brackish water; Indigenous species;