Growth, food and feeding habit with prey preference of long whiskered catfish, Mystus gulio (Hamilton, 1822) in brackishwater traditional impoundments of Sundarban, India

Abstract

The present study was aimed to focus on growth, food and feeding habit with prey preferences of long whiskered catfish, Mystus gulio (Hamilton, 1822) in brackish water bhery for 12 months during August 2014 to July, 2015. Advance fry of M. gulio (1.78±1.5g, 5.6±0.54 cm) added to stock fishes @ 10000 fish/ha attained 82.53.20 g (20.5±0.98cm) in brackishwater impoundments. The fishes showed isometric growth (W=0.007 TL2.996) and good Condition factor (K=0.98±0.07). Feeding intensity observed lower during intense breeding season (May to June) and higher during the post-spawning season (August to April). M. gulio is a carnivorous fish as it used to prey mostly on zooplankton and animal food materials. According to the order of dominance, the major food groups in stomach were Copepods> Insect larvae> Myxophyceae> Rotifers & Cladocera> Crustacean parts> Bacillariophyceae> Chlorophyceae> Fish and prawn larvae> unidentified materials but on prey selectivity analysis, the fish actively selected on positive preference as Copepods> Insect larvae  Fish and prawn larvae> Rotifers & Cladocera> Crustacean parts and negative preference as Myxophyceae Bacillariophyceae Chlorophyceae. Electivity analysis observed that Copepods, Insect larvae, Fish and prawn larvae were most preferred food items to the fish.