Fishing for trout

An engineer brings the cold-water fish to Hyderabad and the Union government seems interested

- BY K. VIJAYA BHASKARA REDDY

THE RAINBOW TROUT is one finicky fish. Native to the cold mountain streams of North America, Europe and north Asia, it demands water temperatures between 10 and 14 degrees Celsius, high dissolved oxygen levels and fast-flowing, clean, gravel-bedded streams to sustain its near-constant movement.

In India, only the Himalayan region (Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim and Arunachal Pradesh) can meet these demands. This is thanks to year-round glacier melt, steep gradients that keep water oxygenated and minimal stagnation, even in summer. No other landscape offers this combination. In fact, efforts by Scottish planters to grow trout in Kerala's Munnar, between the 1890s and 1920s, had failed. Now there is only limited trout presence in Munnar.

In that context, what Aditya Ritvik Narra has built in Hyderabad is remarkable. Through his SmartGreen Aquaculture, he has created India's first inland trout farm, in one of south India's hottest cities, using recirculating aquaculture system (RAS) technology to simulate the necessary conditions. The farm was inaugurated in January by Union Fisheries Minister Rajiv Ranjan Singh, who has, in Aditya's words, become “a brand ambassador for the trout farm”.

RAS is, at its core, closed-loop fish farming. It grows fish indoors. Temperature, air and water quality are controlled and continuously monitored. RAS is widely used for high-value fish like trout and salmon, and shrimp, especially when water is limited or climate conditions are not ideal.