Breakthrough in mariculture: ICAR-CMFRI achieves captive breeding of high value marine fish golden trevally
In a major breakthrough in mariculture development in the country, the ICAR-Central Marine Fisheries Research Institute (ICAR-CMFRI) has successfully developed seed production technology for golden trevally (Gnathanodon speciosus), a high value marine fish. The development is expected to open up a new avenue for sustainable seafood production and boost the country's list of viable candidate species for mariculture. Successful bloodstock development, captive breeding and larval rearing of the fish was achieved after five years of research at ICAR-CMFRI’s Visakhapatnam Regional Centre. Golden trevally or golden king fish is an ideal candidate species for mariculture (marine aquaculture) due to its faster growth rates, good meat quality, and huge market demand for both consumption and ornamental purposes. In domestic market, the fish fetches a price of 400-500 per kg.
It is a reef associated fish and lives in company of larger fishes like skates, sharks, groupers etc. Interestingly, juveniles of this species act as pilots for sharks. It is a silver grey fish with yellowish colouration on belly, with scattered black patches and all fins coloured yellow and a black tail. The juveniles are more golden in colour with the black bands giving them a very attractive look and hence a preference for aquarium keeping. As an ornamental variety, the fish is priced between Rs. 150-250 per piece.
In India, the fish landing observations show that the golden trevally are landed predominantly at reef area fishing grounds in Tamil Nadu, Puducherry, Kerala, Karnataka and Gujarat. The total fish landings estimate for the last five years i.e. 2019, 2020, 2021, 2022 and 2023 was 1106, 1626, 933, 327 and 375 tonnes respectively mainly from Ramanathapuram, Nagapattinam, Chennai, Pudukottai, Trivandrum, Ernakulam, Tirunelveli, Tanjavur, Tuticorin, Udupi and Gir Somnath districts. A team of scientists at the Visakhapatnam Regional Centre of ICAR-CMFRI led by Dr Ritesh Ranjan, Senior Scientist started the research efforts on seed production of this fish in 2019. Juveniles of 40-50g collected from the wild were reared in CMFRI’s research cage farm facility off Visakhapatnam coast. These fish were raised in cages for 3-4 years until they reached maturity (3.5-4.5kg). After separating males and females, the mature fish were transferred to a land-based tank system (RAS) with a 40 cubic meter capacity. Natural spawning occurred within the RAS on February 9, 2024. After 51 days of rearing post-hatch, the early fry reached an average size of 3 cm and attained weight of 450 milligram with very good survival rate.
Milestone in Indian mariculture
“This is a significant milestone in Indian mariculture”, said Dr A Gopalakrishnan, Director of ICAR-CMFRI. “Golden trevally is an ideal candidate for sea farming due to its desirable qualities. Given the declining trend of its landings, the success in captive breeding of this fish has greater significance as it will offer opportunities for sustainable fish farming through mariculture practices including sea cage farming. The technology will also contribute to wild stock restoration efforts through sea-ranching initiative”, he said.
