Diet composition and feeding strategy of Johnius dussumieri (Cuvier, 1830) from Ratnagiri coast of India

Abstract

The present investigation included diet composition and feeding habits of sin croaker (Johnius dussumieri) based on the monthly examination of 1031 specimens along Ratnagiri coast of India from December 2009 to November 2011. Results indicate that J. dussumieri is a carnivore feeder and feeds upon narrow range of food items. Crustaceans were identified as most dominant food items followed by teleost fishes, molluscs and planktonic forms like fish egg and Salpa. The species preferably feeds on a marine crustacean i.e. Acetes spp. The feeding intensity of J. dussumieri was found poor during April and September. The analysis of Kendell‘s coefficient of concordance indicated relatively stronger association (W = 0.64, p < 0.05) of choice of food items with season, while the same did not hold good for different size groups. Therefore, the differential feeding habit was evident among the different size groups. The juveniles preferably feed on crustaceans, while the adults were observed to prefer small teleost fishes. The differences in the diet composition between adults and juveniles indicated the existence of different feeding habitats along the Ratnagiri coast of India.