Current Status of Rainbow Trout, Oncorhynchus mykiss (Walbaum, 1792), Fisheries in Munnar Hills of South India

Abstract

Rainbow trout, Oncorhynchus mykiss (Walbaum, 1792), is a popular cold-water fish species widely distributed and farmed across the globe. In India, rainbow trout fisheries are common in the Himalayan states and the Western Ghats of South India. The introduction of brown trout, Salmo trutta fario (Linnaeus, 1758), in Munnar, Kerala, India, dates back to 1909. As the farming of brown trout was not successful, rainbow trout were introduced in 1932. However, no data regarding trout fisheries post-1970 are available. Hence, this study aimed to assess the current scenario of O. mykiss fisheries by analysing the existing angling and production records and interviewing the officials in charge. The results showed that O. mykiss fisheries in Munnar are currently endangered, and only a few numbers of O. mykiss stock are found in Rajamallay Stream, which is the present stocking site. Studies have shown that destructive fishing, pollution, siltation, and animal intrusion contributed to the decline of trout stocks in this region. Proper conservative measures, good hatchery conditions, adequate broodstock management, feed improvement, and regular seed stocking can improve the production of O. mykiss in Munnar.