DOI: 10.36347/sjavs.2014.v01i03.002

Pages: 107-114

Freshwater snail, Viviparous viviparous constitutes a component of the tribal diet of Goalpara district, India, where tribal community viz. Rabha, Boro, Garo, Hazong (36.10%) lives together. They normally collect snail from natural sources and are not aware of snail farming technology. Snail habitats are naturally degraded due to various reasons viz. degradation of aquatic environment due to shrinkage of water bodies, eutrophication, human interferences, use of agrochemicals in modern agricultural practices and animal husbandry. An investigation was conducted during 2010-2011 on freshwater snail habitats in the district. Five habitatsviz. (i) shallow stagnant water body, (ii) slow moving water body, (iii) beel, (iv) rice-field and (v) river, were identified. Environmental parameters viz. pH, dissolved oxygen, carbon-dioxide, hardness, temperature, water movement, vegetation and co-relation analysis was done against snail population. Highest population was found in riverine habitat (100 numbers in 23 sampling in a year) followed by beel habitat (90 numbers in 23 sampling in a year), stagnant water body (88 numbers in 20 sampling in a year), rice-field (76 numbers in 15 sampling in a year), slow moving water body (59 numbers in 15 sampling in a year). The analysis reveals that water movement, pH, depth and vegetation are the responsible environmental factors for snail population. Snail population was found higher within the range of pH 5.4-6.5,depth 0.1-0.5m.The study indicates that snail population is higher in riverine habitat due to continuous supply of running water which carries food for snails in the form of dead algae and second highest in beels which are infested with aquatic vegetation that provides feeds for snail. The study reveals that feed and other environmental parameters viz., water movement, pH, depth, are the limiting factors for snail population in the natural sources.The study suggested that the snail habitats may be managed in an eco-friendly way