Fishing for a solution
Fueled by increasing poverty and demand for land, slash-and-burn agriculture practised in sub-Saharan Africa is putting forests under threat and resulting in the desertification of many millions of hectares of rainfed cropland. In addition, fish remains the major component of animal protein intake in a number of countries and is especially important among the poor. And yet, in most regions of Africa, availability of fish has declined steadily over the last decade and the magnitude of shortfall is increasing. But could aquaculture integrated with agriculture be the answer?
Although integrated agriculture-aquaculture (IAA) is common in different forms across Asia (see Integrating aquaculture), the system is not widely practised in Africa and, until recently, neither has it been promoted as a means of increasing not only fish production but overall farm productivity. However, IAA is seen as an efficient and environmentally friendly food production strategy which, in Malawi, has been shown to produce up to 6-fold improvements in profitability. Average fish productivity of integrated smallholdings in Malawi is about 1500kg/ha/yr compared to an average of about 900kg/ha/yr from the most productive non-integrated fish farms and yet, by most estimates, Malawi is a low potential country for aquaculture due to not only its generally low and highly variable rainfall, but also its poor market infrastructure. Tthe potential of agro-pisciculture in countries with more water and better developed markets, for example Cameroon, is likely to be much higher.
At the base of the Zomba plateau in southern Malawi, integrated aquaculture technologies promoted through the innovative Farmer-Scientist Research Partnership with ICLARM have proved particularly profitable. Starting small is the key to success. The tiny farms on the plateau, usually less than a hectare, are not sufficient to produce ample food for everyone. However, even with a small pond, farmers were able to see the benefit and soon found reasons to improve the system themselves. For instance, one community decided to dig some ponds, to be managed for the benefit of the entire village. The villagers already get protein from the beans and cowpeas that they grow but they value the added benefit of the tilapia raised in the ponds. Although the community already raises enough fish to sell the surplus at the local market, with water supplied year-round from the run-off mountain springs, the community intends to expand the ponds and start a rice-fish system as well.
On the other side of the plateau, aquacultural activities are dependent on the yearly rains rather than the running springs, which means that the ponds are dry for part of the year. However those farmers who have embraced integrated aquaculture, have found that at any time of the year they have something to sell whether it is fish, fruit or vegetables. The plant waste is used as fish feed and, when the fish are harvested, the dry pond is fertile and ideal for rice planting. With year-round ponds an average of 1650 kg/ha/yr of fish can be harvested and yet surprisingly, for the rain fed ponds productivity is still more than 1300 kg/ha/yr.
In Cameroon, there is a high demand for fish with 50,000 tonnes imported each year and yet integrated aquaculture is only in its infancy. However, the water and soil resources of the narrow valley bottoms offer an ideal environment for smallholder fish culture within existing farming systems. Lower population densities and better market access also mean that agriculture has a more commercial orientation than in Malawi, where resistance to drought is a critical issue, which means that in Cameroon, promoting market-driven increases in fish output should be possible. In addition, new rural association laws in Cameroon have led to the establishment of thousands of village groups which, with the many NGOs active within the country, offer opportunities for increased dissemination of appropriate information.
In a newly established project, ICLARM intends to test the robustness of methods and approaches developed in Malawi to measure the true potential of integrated aquaculture, particularly in the forest margins, in a country rich with promise. By converting staple food surpluses into fish it is hoped that farmers will be able to produce a high value, high protein commodity that has a ready and flexible market.