All over Africa South of the Sahara, fish consumption is increasing among our increasing populations, and aquaculture has been determined to be the most viable means of plugging the gap between demand and supply. Almost all countries are implementing aquaculture development strategies, and low to moderate levels of success have been achieved overall. But there is certainly a need to maximize output beyond current production levels, and one viable option, it appears, is to diversify the species under production beyond the usual tilapia and catfish. There are a good number of local species known to be potentially viable for commercial aquaculture. But not much work is being done in this area. Rather, some foreign species with apparently good prospects for commercial production have already been deployed, mainly in Nigeria, and are showing good results. But there are concerns that even though they have great potential to increase output and profitability of fish farming, foreign species need to be evaluated technically for their potential negative effects.
Due to the sharp decline of marine fish output, most African governments – which are already facing major foreign exchange supply challenges – import large amounts of fish to support demand. The trend is most likely to continue, because beef production is declining, due mainly to scarcity of grazing land. By promoting aquaculture, they expect to reduce their import bills. But tilapia and catfish output figures have been lower than expected, and the idea of species diversification has gained prominence. A number of species local species have been identified as good potential candidates for commercial aquaculture in Africa, but they require some research work to facilitate deployment. In the last couple of years, some foreign species have been brought under commercial production, and appear to be doing well. Brama, common carp, pangasius and pacu are some of these species. Among the considerations for their promotion are their lower feed costs, their large harvest sizes, their toleration of high densities and their sturdiness. But concerns have been expressed that whilst these new species may deliver increased output and profitability in the short and even medium term, the potential dangers are significant, and need to be seriously considered.
The cost of feed is a major challenge facing fish farmers in Africa, accounting for at least 70% of their budgets. Maize is the main ingredient of fish feed, but it is also the main food source for most Africans, and it is also a major industrial raw material. The situation is further complicated by speculators who buy maize from Nigeria and Ghana and sell it to buyers in Sahelian West Africa for hard currency. Due to low domestic production, livestock farmers in West Africa import soya meal, the main protein ingredient in poultry, fish and pig diets. Efforts are being made to reduce feed costs. Soya production is expected to rise appreciably in the next five years, and serious attempts are being made to deploy alternative ingredients in commercial production. But for now, fish farmers find it convenient exploiting foreign species whose demands on their feed budgets are minimal. Some efforts are being made to produce commercial fish feed from alternative feed sources, and experts believe that the cost of fish feed could be reduced by 30 per cent in only a few years. In the meantime, the deployment of foreign species is gathering momentum.
One of the main risks of producing foreign species under capture conditions is their escape into rivers, lakes and other water bodies. Apart from the great difficulty of keeping them safe in fish farms, the recent floods experienced in West Africa swept across numerous cages and ponds, and foreign fish species should be all over the place by now. This risk is further increased when one considers the fact that West African borders are porous, to say the least, so all manner of goods and services flow through. Currently, about half of the fingerlings used by Ghanaian fish farmers are illegally but freely imported from Nigeria. There is the real risk, then, of pangasius, pacu, common carp and other species finding their way across West Africa, exposing water bodies to various risks.
There are many local fish species with good potential for deployment in aquaculture, and African aquaculture experts have done some work which indicate good prospects. But most of these projects require funding to complete investigations.
Presently, there seems to be a general acceptance of the need to increase aquaculture production to plug the wide gap between fish supply and demand. Aquaculture is the best means of providing sufficient protein for the increasing numbers of Africans. Clearly, the production of foreign species with virtually no restrictions is being done with the view to increasing output figures, and to increase profitability for the fish farmer. But the risks are very real. They could manifest much sooner than later.