Selective feeding behaviour of the common carp Esomus danricus (Ham.) in its natural habitat

Food selectivity by the common freshwater carp, Esomus danricus (Ham.) was studied through Ivlev's equation of electivity. The selective feeding seemed to be influenced by many factors, including the accessibility, abundance and taste, of the food items, the mechanical and physiological adaptations on the part of the fish to capture and digest those food organisms, as also the inherent and instinctive property of the fish to prefer certain types of food over the others. The absence of strong specific selectivity by the fish for a variety of planktonic food organisms was found to be a phenomenon compensatory to stenophagism, in order to make use of whichever food items remained in the habitat at the time when the preferred genera of plankton were not available, due to the process of succession.