Rice-Fish farming is the integrated, simultaneous culture of rice and fish in irrigated rice fields or paddies. It is an old practice that is believed to have begun in China 1,700 years ago.
By Dr. Rafael D. Guerrero III
In 1948, the Food and Agriculture Organization (FAO) of the United Nations recognized the importance of rice-fish culture for addressing world malnutrition and poverty. With 90% of the world’s rice produced in 134 million hectares (ha) under flooded conditions, rice-fish farming is extensively done today in many Asian and African countries.
In the Philippines, interest in rice-fish farming was generated by field experiments conducted
at the Freshwater Aquaculture Center of the Central Luzon State University (CLSU) in Nueva Ecija in 1974. Through the efforts of the Department of Agriculture’s National Food and Agriculture Council (NFAC) starting in 1982, there were 2,284 farmers applying rice-fish culture in 1,397 ha of irrigated rice fields in the country until 1986, when the national program was discontinued.
In 2014, the Philippine Statistics Authority (formerly the Bureau of Agricultural Statistics) reported that a mere 2.17 tons of tilapia was produced in rice-fish farms in Eastern Visayas and other parts of the country, with an estimated area of less than 100 ha.
Rice-fish farming has many economic, social and environmental benefits. For one, even with a reduction of 10% in the area of the rice field devoted for the fish refuge, there is an increase in the yield of rice by 14-48% in addition to fish production of 5-174 kilograms (kg)/ha. According to a study conducted by Reuben Sevilleja of CLSU in 1992, rice-fish farming in the Philippines gives a 27% net return.
Studies in China have indicated that growing rice and fish in the same area reduces labor by 19% and results in 4-14% lower costs for fertilizer and other inputs. There was also a decrease in the incidence of malaria in Indonesia from 16.5% to 0.2% in areas with rice-fish farms due to the eradication of mosquitoes breeding in stagnant waters.
In rice-fish farming, the fish (mainly the Nile tilapia in the Philippines) helps in fertilizing the rice through its manure and also contributes to insect pest control. There is also more aeration of the rice roots and less release of the “greenhouse gases” that aggravate climate change from the paddy bottom because of fish agitation.
In applying rice-fish culture, an abundant supply of water from an irrigation or underground source is a must. Trenches or canals measuring 0.5-1 meter (m) wide and 0.4-0.5m deep are dug in the paddies at the center and/or sides to serve as fish refuges or shelters when the water is drained for rice harvesting.
With a water depth of 2.5-15 centimeters (cm) in the paddies, tilapia fingerlings are stocked at 0.25-1/square meter1-2 weeks from transplanting of the rice seedlings.To prevent the entry of predators like mudfish and catfish and the escape of the cultured fish, a wire or fine-mesh net screen is placed at the water inlet. Application of chemical fertilizers such as ammonium sulfate and insecticides which are toxic to fish is avoided. Use of organic fertilizers like vermicompost is recommended. The fish are collected from the trenches after 2-3 months of culture following the rice harvest.
As part of its advocacy for sustainable fisheries, the Philippine Fisheries Association is promoting the revival of rice-fish farming in the country. For more information, interested readers may contact the PFA through email at pfa1999@ outlook.com.
This appeared in Agriculture Monthly’s March 2016 issue.