WWW.WAS.ORG • WORLD AQUACULTURE • DECEMBER 2017 27 In recent years, fisheries and aquaculture has gained increasing importance and the sector has registered impressive growth in India. North Eastern Region (NER) is considered to be one of the global hotspots of freshwater fish biodiversity (Kottelat and Whitten 1996), harboring about 267 fish species (Sen 2000). The state of Meghalaya is rich in natural aquatic resources in the form of rivers, lakes, reservoirs, beels, ponds, and tanks. However, these resources are not yet fully exploited for fisheries and aquaculture development, although great potential exists. Meghalaya is one of the important states in NER, where 95 percent of the population consumes fish and fish is used for various social functions. The state produces about 5000 t annually against an annual requirement of about 11,000 t (meghalaya.gov.in). To meet the shortfall, the state imports freshwater fish, mostly from Andhra Pradesh. Knowledge of scientific fish farming has yet to reach majority of fish farmers for expansion and intensification of aquaculture. There is tremendous potential for increasing productivity and ensuring environmental integrity and food safety through introduction of suitable fish species and technology appropriate to the region. The ICAR-Research Complex for NEH Region and KVK, Ri-Bhoi has initiated an attempt to introduce rice-fish culture following two rice plot design systems in Ri-Bhoi District. Rice-Fish Culture Trials in North Eastern Region of India Arun Sharma, Sanjay Kumar Das, Rajumani Bordoloi and Thongam Ibemcha Chanu Preparation of Rice Fields and Fish Culture The trials were conducted in the villages of Kyrdem, Sohrublei, Mawtneng, and Nongthamai. The villages have low-lying rice fields with high rainfall and poor drainage where water remains in the fields for a 4-5 mo period each year, with an average water level of 50-75 cm in most areas. Soils are mostly medium-textured, such as silty clay. Dikes enclosing the rice plots are 30 cm high and 30 cm wide. Simultaneous co-culture of rice and fish was practiced. Each rice-fish system had a fish refuge (1 m × 1 m × 1 m), consisting of a pit, pond, trench or low point in the rice-fish field (Figs. 1 and 2). When the rest of the field is dry, fish can be held there. Two types of rice plot designs were prepared, both with fish refuges, one with a peripheral trench system (Fig. 3) and the other without a trench system. Peripheral trenches (side channels) were 75 cm × 75 cm (Fig. 4). Peripheral trenches were connected to the main water supply, on either side of which rice plots were located, through inlet-outlet structures of the dikes. The refuge was connected to the side channel through a central cross trench. Bamboo pipes and screens were placed in the inlet and outlet structures to avoid the entry of predatory fish and the escape of cultured fish. (CONTINUED ON PAGE 28) FIGURE 1. A refuge/fish pit/ trench in a rice-fish plot. FIGURE 2. Rice-fish plot with a refuge but no peripheral trenches.
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