Raise Fish in the Rice Paddy

AquacultureCrop production

Script

Rice paddies have lots of natural food for fish. This is one of the advantages of raising fish and rice together. Fish help the farmer by eating weeds and insects in the paddy field. And they fertilize the rice with their manure. On top of all this fish is a nutritious food for your family.

Today we will talk about what you need to do to keep fish in a rice paddy.

Making a pond

You will need a pond for your fish so they will have a place to go when you harvest your rice or when there is a shortage of water. Choose an area of the field that holds water. This is often the lowest spot in the field.

Your pond should be about 6 metres square and about 1 metre deep. Slope the sides of the pond to help prevent erosion. Add the soil that you dig out of the pond to the sides of the pond or paddies to help prevent the pond from overflowing when you have heavy rains. You can also help prevent erosion by growing plants on the banks of the pond.

One side of the pond should open into the rice paddy. This way the fish can swim in and out of the pond, and the pond will be a refuge for the fish when the water level is low. When you drain the paddy for the rice harvest, do it slowly to give the fish time to retreat to their pond. When the field is drained, all the fish will be in the pond and they will be easy to catch. If the fish are not yet big enough to eat, you can feed them in the pond until the field is ready for rice again.

Stocking the pond

To get started you will need a supply of fish. Some of the common fish species used by farmers are carp, tilapia, and catfish. When you are deciding what kind of fish to raise you may be restricted by what is available at the nearest hatchery. Or maybe a neighbour who raises baby fish for rice fields has extra to sell.

If you are going to have more than one kind of fish, you must make sure they can live together easily. For example, catfish eat other baby fish. If you keep only catfish you may have to buy or raise small fish to feed them.

The advantage of using local fish species and varieties is that they live easily in your area. When you import fish you may also import some problems such as diseases. Use local fish if you can. If not, check with your agricultural representative to see which species are available and best suited to your area. Transporting fish is stressful for the fish and should always be done as quickly as possible. So the closer your fish supply is, the better it is for the fish. When you get your baby fish, leave the container of fish sitting in the paddy until the water in the container is the same temperature as the water in the paddy. The fish can then be let out into the paddy.

Fish dig and swim around rice plants searching for food. If you stock your paddy with large fingerlings (fish that are the size of your largest finger) make sure that your rice plants are well established before you put the fish in your paddy.

Feeding fish

Fish will do well eating weeds and insects in your rice. However, if you want your fish to grow bigger and faster, you can give them extra feed. There are lots of things around your farm that the fish like. They will eat kitchen scraps, grass clippings, livestock manure, rice bran, insects, chopped vegetables, chopped papaya leaves, and crushed snails.

Fish need oxygen

Fish and plankton both use oxygen from the water. If there is too much plankton there will not be enough oxygen in the water for the fish. So keep an eye on the plankton levels in your paddy. If there is not enough oxygen in the water for the fish they will come to the surface and gasp for air. When you see fish gasping you should increase the level of oxygen in the water by adding fresh water or by creating lots of air bubbles in the water by stirring it hard with a branch. Also, cut back the amount of food you are giving the fish. Your experience will soon tell you what is the right amount of food.

Here is a good way to judge the amount of plankton present. Plankton gives the water a brownish green colour and makes the water cloudy. Put your arm in the water up to your elbow. If you can see your hand, you can add more food to the water. Ideally you should be able to see at least half way down your arm. If you can’t, then there is too much plankton and you should stop adding feed. If the fish are gasping, add fresh water.

Remember that pesticides kill fish and the food that fish eat. So if you are going to keep fish in a rice paddy you must have good quality water without any pesticide residue or runoff.

Acknowledgements

  • This script is based on “Rice fish culture”, pages 69 71 in 101 Technologies from the South for the South, 1992, published and available free of charge in English and French from the International Development Research Centre (IDRC), P.O. Box 8500, Ottawa, Canada K1G 3H9. This booklet features technological innovations in agriculture, forestry, energy, and health, that were developed in the south and researched with funds from IDRC. The production of this script and others from 101 Technologies was funded by the International Development Research Centre.
  • This script was written by Sarah Nettleton, Researcher/Writer, Guelph, Canada. It was reviewed by Dr. Saidu Koala, Senior Program Officer, Environment and Natural Resources Division, International Development Research Centre (IDRC), Ottawa, Canada.

Information sources

  • Farmer proven integrated agriculture aquaculture: a technology information kit, 1992, International Institute of Rural Reconstruction (IIRR), Silang, Cavite, Philippines, and International Center for Living Aquatic Resources Management, (ICLARM), MCPO Box 2631, 0718 Makati, Metro Manila, Philippines.
  • Low external input rice production technology information kit. The Information Service Unit, International Institute of Rural Reconstruction, Silang, Cavite, Philippines.
  • Rice fish culture, Greg Chapman and John Sollows, The Sustainable Agriculture Newsletter, Vol. 2, No. 1, March 1990, 16 pages. CUSO, 17 Phahonyothin Golf Village, Phahonyothin Road, Bangkhen, Bangkok, 10900, Thailand.
  • A hatchery manual for the common, Chinese and Indian major carps, V.G. Jhingran and R.S.V. Pullin, 1985, 191 pages. Asian Development Bank and the International Center for Living Aquatic Resources Management (ICLARM), Manila, Philippines.
  • Fish farming, 1982, 72 pages. Inades Formation, 08 B.P. Abidjan, Ivory Coast.
  • Rice fish research and development in Asia, Catalino R. de la Cruz, 1992, 400 pages, ICLARM Conference Proceedings 24.
  • Farming Systems Research Institute, Department of Agriculture, Bangkhen, Bangkok 10900, Thailand. Sukamandi Research Institute for Food Crops, JI Kakya 9, Sukamandi, Subang, West Java, Indonesia.