Ecology and Population Biology of Freshwater crab Barytelphusa Guerini H Milne Edwards in Godavari River Basin and its Tributaries in Marathwada Maharashtra

Abstract

Freshwater crabs are among the most important invertebrates inhabiting Indian sub-continent waters and these large and conspicuous crustaceans are present in almost all freshwater habitats from mountain streams to large lowland rivers and smaller water bodies (Bahir and Yeo. 2007). Freshwater crabs are ecologically as well as economically owing to their role in nutrient cycle, water quality monitoring and small-scale fisheries have been considered as important group. About 1280 species under 4 super families occur in the world, which accounts to one fifth of known brachyuran diversity (Cumberlidge et al., 2009). A total of 96 species under 41 genera in 6 families hitherto recorded from India is presented here (Wood-Mason, 1871; Henderson, 1893; Alcock, 1910; Bott, 1970; Bahir and Yeo, 2005, 2007 and Ng et al., 2011). newlineThere are five species belonging to three families viz. Sesarmidae, Varunidae and Hymenosomatidae, the members of which are either marine or estuarine forms. However, some of the members belonging to these families have adapted to live in and complete their life cycle in freshwater habitats and need not have to return to the sea (Ng, 1988). As such, these have been considered as freshwater species. All species belonging to the genus Gecarcinucidae are fresh water. newlineThe past few decades has seen an upsurge of interest in the using freshwater crabs as ecological model for assessing impact of various environmental stress and pollutant in the rivers (Jadhav, et al., 2011). A number of studies have showed that various chemical pollutant and pesticides have affected the population structure of the crabs in the Godavari basin (Venugopal, et al., 1997). This has resulted in a steep decrease in the populations of the crabs in the region (Thankar, 1985). Freshwater crab B. guerini have been repeatedly investigated for behavioural and various physiological studies. The effect of various inorganic ions, drugs and antibiotics, pesticides, heavy metals has been used by many workers to screen the various properties