WWW.WAS.ORG • WORLD AQUACULTURE • MARCH 2024 53 monoculture. Captive production of chital will not only address the market demand but also alleviate the fishing pressure on its wild populations, thereby aiding the recovery of beleaguered stocks in their native aquatic environments. By incorporating these fish into controlled farming practices, a consistent market supply can be ensured, effectively mitigating occasional price spikes that can reach levels of USD 18 to 24/kg. Chital, a markedly predatory fish, presents a noteworthy opportunity for co-cultivation alongside counterparts like tilapia and other self-recruiting species, including Mola carplet (Amblypharyngon mola) and barbs such as Esomus danricus and Puntius sopore, which function as inherent bait, prey, or sustenance forage (Fig. 3). This innovative approach, recognized as predator-prey aquaculture (PPA), was subject to an initial investigation at the ICAR Tripura Centre. This study encompassed three modestly sized ponds, each spanning 168 m2 (14 m x 12 m x 1 m), wherein A. mola was employed as the forage fish. Specifically, Pond I accommodated 500 Mola fish, Pond II harbored 1000 Mola fish, and Pond III held 1500 Mola fish. Following a month’s time, chital were introduced into each pond at a rate of 100 fish per pond. Over the subsequent year, operating solely on forage fish and plankton without external feeding, the chital production was estimated at 54 kg (98 percent survival) in Pond I, 60 kg (95 percent survival) in Pond II, and 58 kg (90 percent survival) in Pond III. Simultaneously, added production of A. mola occurred, approximating 10 kg, 18 kg, and 20 kg in the respective ponds. Another trial, conducted in Dhalai, Tripura, within a backyard pond measuring 0.08 ha and stocked with chital at a density of 1200 individuals/ha, yielded cumulative fish production ranging from 560 to 820 kg, with survival rates ranging from 62 to 72 percent across a 10-month period (Fig. 4). While specific information about the optimal water quality requirements for this fish is lacking, our studies have revealed that the fish performs well under normal pond conditions. These conditions encompass water temperatures ranging from 22.1° to 32.6° C, dissolved oxygen levels ranging from 3.5 to 6.8 ppm, pH levels between 6.9 and 7.8, total alkalinity within the range of 37.4 to 66.5 ppm, water transparency spanning 24.2 to 38.8 cm, nitrate concentrations ranging from 2.2 to 4.8 ppm, nitrite levels between 0.6 and 1.2 ppm, phosphate levels at 0.25-0.84 ppm, and plankton density at 3.4 to 4 ml per 50 L of water. Similarly, there is no specific guidance available about the optimal soil quality requirements for this fish; however, our studies have shown the fish thrives under standard pond conditions, characterized by a soil pH range of 6.1-6.3, available nitrogen concentrations ranging from 14.4 to 19.3 mg/100g, available phosphorus levels between 0.3 and 0.7 mg/100g, and organic carbon content within the range of 0.3 to 0.7 percent. Feed Chital exhibit sigmoid growth in pond condition and grow to an average size of 560 g to 650 g in 10 months with no external feeding, sustaining themselves exclusively on forage fish (Mola carplet) and plankton. A growth of 950g was recorded in 10 months in Dhalai district of Tripura under an on-farm trial (OFT) with supplementary feeding with pelleted feed (20 percent crude protein) and tilapia as a forage fish. In this OFT, the fish grew to an average size of 750g when solely reared on forage and 850g when solely fed with pelleted feed. This indicated that by adopting a feeding strategy including forage fish in combination with supplementary feed, the growth rate can be improved. Besides serving as a direct food to chital, supplemental feed provides essential nutrients for the proliferation of plankton and forage fish. Economic Appraisal Engaging in chital farming presents a promising avenue for a highly lucrative fishery-based livelihood. This is attributed to the competitive pricing that chital fish can command in the market. By adopting diverse feeding strategies, outlined in the table below, prospective farmers can achieve net benefits ranging from USD 2406.00 to 3608.00 /ha through their rearing efforts. When juxtaposed with carp fish farming practices followed by farmers, chital farming in backyard pond settings emerges as remarkably advantageous. Even when managed under low-input conditions, it has the potential to be 2 to 3 times more profitable. Given these compelling prospects, chital farming is strongly recommended as a viable and potentially lucrative avenue for livelihood enhancement (Table 1). (CONTINUED ON PAGE 54) FIGURE 3, LEFT. Chital performs well in polyculture. FIGURE 4, RIGHT. 10-month old Chital.
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