Sunday, September 28, 2008

Fish farming gist

I was at the Launching of Aquaculture Best in Lagos in August. It's a trade magazine on raising fish. No, I'm not becoming a farmer (a cultivator of minds perhaps) but I'm surprised how many fish farmers I know. And now that I've moved into agricultural country in Adamawa's Upper Benue River Basin...

One plot of land, twice the food

Combined rice/fish cultivation is a highly efficient agricultural practice - yet its potential remains largely untapped
11 May 2005
For as long as there have been rice paddies, farmers have been capturing and raising fish in the water along with the rice. Indeed, few plant-animal combinations are more suited for growing together to improve nutrition and alleviate poverty, says a new book on the subject jointly published by FAO and the Malaysia-based World Fish Centre, Culture of Fish in Rice Fields.

This interview with one of the book's editors, FAO's Matthias Halwart, looks at the ways that rice/fish production contributes to food security in Asia -- and what potential the practice holds for other regions.

Q. What is rice/fish farming?

Basically, fish are raised in a flooded rice field and farmers harvest both the fish and the rice. But while the term "rice/fish" is often thought to refer only to the simultaneous culture of rice and fish in one paddy, it in fact includes other methods, like the rotational system, where a crop of rice is followed by one of fish, or systems in which fish are raised in ponds adjacent to the rice, with water resources shared between the two. It's an extremely efficient way of using the same land to produce both carbohydrates, in the grain, and animal protein, in the fish.

Q. Are there other advantages?

Well, to feed the fish you can simply rely on the aquatic plants and animals naturally occurring in the field. Supplemental feed doesn't have to be purchased -- it's often agricultural by-products normally found on a farm -- vegetable matter, manure, etc.

And the fish help control weeds by eating or uprooting them, and also feed on insect and snail pests. Interestingly, pesticide use on rice/fish farms is greatly reduced, if not eliminated. Although this is motivated by wanting to protect the investment in the fish, it really is a good practice both for farmers and the environment because scientific evidence shows that in nearly all cases insecticides are not needed in tropical irrigated rice.

The fish may also play an important role in the nutrient cycle of the rice field, increasing its fertility while reducing fertilizer requirements.

Q. What does this mean for farmers and their families?

The practice has great potential for food security and poverty alleviation, especially in more remote areas.

Adding fish to the field not only results in new yields of fish protein and reduced input costs -- it actually produces better yields of grain. The book cites several studies that illustrate how this plays out. In Bangladesh, the net return from rice/fish farms was over 50% greater than in rice monoculture. In China, the increase ranged from 45 to 270%, and growing fish with rice was almost three times more profitable than just growing rice alone.

There are less obvious benefits, too.

Q. Such as?

A wet rice field has a surprisingly great biodiversity, which is a rich source of edible organisms. One study in Thailand found that one vegetable and 16 different animal species were being harvested in a single rice field. Another in Cambodia reported that over 100 different plant and animal species -- for example, shrimp, crabs, shellfish, turtles, frogs, even insects and snakes -- are being collected by farmers and used in rural households for food or medicine. All these rice-associated aquatic species are important for the nutrition of rural people, containing proteins, minerals and fatty acids essential for a balanced diet.

Q. Despite the benefits, this practice is still largely limited to Asia...

That's right. The adoption of rice/fish farming has been low, for various reasons -- even in Asia. China has 1.2 million hectares used for rice/fish farming, but that is less than four percent of its irrigated land area. In other parts of Asia, perhaps only one percent of irrigated land is being used this way. One exception is Madagascar, with almost 12% of rice land being integrated with fish. And other countries, for example Guyana and Suriname, are now making efforts to popularize this integration.

Q. Why isn't rice/fish farming more widespread?

A rice field is by design intended for rice production, and conditions are not always optimum for fish, so shifting over requires work -- and investment. You need to increase the height of dikes, dig trenches and ponds, construct weirs and methods for moving water, add fish screens. That's one hurdle.

And policymakers haven't really appreciated its potential. Rice/fish farming is often considered a novelty that does not merit consideration in national rice production strategies. In our book we conclude that a fundamental shift in attitudes towards rice/fish farming in the traditional rice production sector is required.

Previously on UpNaira