Growth performances, feeding ecology and prey preferences of tade mullet, Liza tade (Forsskål, 1775) in extensive brackishwater farming system

Abstract

Present study was conducted to assess growth performances, feeding ecology and prey preferences of tade mullet (Liza tade) in extensive polyculture for 9 months during February to November, 2015. Impoundments were filled with unfiltered estuarine water (17.2ppt) containing seeds of various crustacean and fish species and water was exchanged (20-30%) every lunar cycle through bamboo screens. No feed or fertilizer was applied following common practice. Tade mullet fingerlings (4.24±0.76g) added with auto stocked fishes @ 2000 fish/ ha attained 260.4110.50 g. They showed negative allometric growth (W=0.007 TL2.951) indicating shortage of food materials in extensive farming system. Feeding intensity in terms of stomach fullness increased with increasing fish weight. Feeding ecology study indicated tade mullet as herbivorous fish grazing on phytoplankton and organic matter from the bottom sediment. Although tade mullet fed on Bacillariophyceae, Myxophyceae and Chlorophyceae according to the order of dominance, they actively selected Chlorophyceae followed by Myxophyceae and Bacillariophyceae according to order of preference indicating their ability to select preferred food items.