Polyculture of a Critically Endangered Olive Barb, Puntius sarana (Ham.), with Indigenous Major Carps in Earthen Ponds

Polyculture of olive barb with indigenous major carps was carried out for 8 mo at different densities in earthen ponds. All the experimental ponds were stocked with fingerlings of major carps viz., catla, Catla catla , and rohu, Labeo rohita , at the rate of 3750/ha each. In addition, olive barb, Puntius sarana , was stocked at the rate of 10,000, 12,500, and 15,000 fingerlings/ha in treatment‐1 (T 1 ), treatment‐2 (T 2 ), and treatment‐3 (T 3 ), respectively. Fish in all the ponds were fed with supplementary feed comprising of rice bran (70%), mustard oil cake (25%), and fish meal (5%) at the rate of 3–6% of the estimated body weight. Physicochemical parameters and plankton populations of pond water were within the acceptable range for fish culture. The mean final weight, weight gain, and specific growth rate of catla were very similar in all the treatments while those for rohu and olive barb were significantly higher in T 1 than in T 2 and T 3 . The gross and net productions in T 1 were significantly higher than in T 2 and T 3 . The net benefit was also highest in T 1 followed by T 2 and lowest in T 3 . Under the conditions of this experiment, growth, production, and benefits were greatest at a stocking density of olive barb at 10,000/ha in polyculture with other major carps.