Feeding ecology of the endemic freshwater puffer fish Carinotetradon travancoricus (Hora & Nair, 1941) in Western Ghats hotspot, India

The study aimed to investigate the feeding ecology of a vulnerable freshwater puffer fish, Carinotetradon travancoricus from the Chalakudy river of Kerala, Western Ghats, a biodiversity hotspot of India. Fishes were sampled from October 2018 to September 2019. Stomach condition of the fishes showed the percentage of empty gut to be significantly higher during all seasons ( P < 0.01). Feeding intensity depicted the fish to follow an ‘active’ feeding strategy (31.59±10.32%) during pre-monsoon season. Diet composition and relative length of gut analysis indicated that the fish during its early stages relied on an omnivorous diet however preferring autochthonous food materials such as insects (27.91%) and crustaceans (25.30%) during its adult stages. A perceptible variation in the feeding strategy associated with the spawning season of C. travancoricus was also noticed. During their spawning season (May-August), a greater preponderance towards animal matter (52.18%) was noticed in their diet. The results of gastrosomatic index indicated that feeding activity of C. travancoricus is considerably reduced (2.99) during the spawning period. The present study provides the baseline information on the feeding ecology of C. travancoricus which could be helpful to aquarists for breeding and rearing of this species in captivity and thereby reducing their fishing pressure in wild.