Food and feeding habits of Macrobrachium lar (Decapoda, Palaemonidae) from Andaman and Nicobar Islands, India

The stomach content of the freshwater prawn Macrobrachium lar from the inland water bodies of Andaman and Nicobar Islands were analysed in relation to size, sex and season during the period from January to December 2008. Feeding habits of M. lar were studied using the index of preponderance and feeding intensity methods. Mainly organic detritus, supplemented by animal and plant materials formed the food in all stages of M. lar. The animal food items mainly consisted of aquatic insects, polychaetes, other crustaceans, fish, molluscs and zooplankton. The plant matter was chiefly composed of fragments of aquatic plants, planktonic algae and diatoms. Variation in diet in relation to size, sex or season were found insignificant. Though, all size groups of this species feed animal and plant materials, it exhibited slight preference for animal food especially in larger size groups. Females appear to feed more actively than the males. Feeding intensity was more in monsoon season compared to dry season. Results indicate that the adults are mostly predators of slow moving benthic invertebrates rather than detritus feeders/scavengers