Fishing in man-made ponds
A correspondent writes on an exhibition of fish farming.The international exhibition on new and appropriate technologies in artificial fish reproduction and the utilisation of inland water resources for fishing activities which took place in Moscow in early August was attended by representatives of more than 20 countries. The object of the exhibition, according to the organisers reports, was to expose the participants to the science and technology of Soviet fish farming methods particularly current Soviet resources and expertise for breed- ing artificial stocks as 'seeds' for replenishing declining fish populations in the seas and inland waters.
Ghana's representatives at the exhibition, the Secretary for Agriculture, Dr I.K. Adjei-Maafo, his Director of Fisheries, Mr V. Dowuona, and Mr Ocran of the Mankoadze Fishing Company, on their return home, expressed their determination to intensify fish farming and encourage artificial breeding of fish in the country to supplement the nation's protein requirements.
Fish farming is one of the emerging small-scale agro-based ventures which is slowly gaining acceptance and wide practice in many developing countries. It is the artificially controlled rearing or breeding of all kinds of edible fishes, crabs, molluscs, oysters, prawns etc, in man-made ponds, purpose-built tanks, in lagoons and lakes, such that fish farming can even be undertaken in forest or savannah areas. It is an industry that has immense potential benefits particularly for landlocked countries because, where successful, it can ensure sufficient dietary protein all the year round with the ability to arrest the chronic problems of malnutrition.
Consequently, fish farming has become a serious occupation in West Africa in recent years due to the frequent shortages of fish foods in those tropical rainforest areas lying between the Gulf of Guinea and the edge of the Sahara Desert. People in these areas will no doubt from time to time crave salted or smoked fish products. Thus changing attitudes in taste and the lack of adequate transportation network to haul fresh sea catches to the hinterlands have all combined to create markets for "locally grown fish" and as a result, 'backyard oceans' had become a catchphrase in several parts of Ghana, Ivory Coast and Liberia.
In Ghana, for instance, fish farming has become an income-earning occupation for most of the 'returnees from Nigeria' who take up fish farming partly to invest their acquired capital and partly as their contri- butions to the national agricultural development effort.
Fish farming has been slow to develop and take off because of lack of interested manpower, expertise and enough rearing stock for regeneration. Feeding matter to sustain artificially set-up aquatic systems was initially difficult to come by until manure and other agric wastes proved to be useful. Furthermore, technical and ecological knowledge about the industry such as behaviour and reproductive patterns, degree and problems of co- habitation of different species, the salinity, alkalinity, temperature and oxygen levels of waters, etc, etc, are not sufficiently developed although there are indications that several local and inter- national agencies and research groups are pooling resources together to sustain the industry. The above-cited exhibition held in Moscow is a classic example.
In the francophone countries of West Africa, the Centre Technique Forestier Tropical (CTFT) has been involved, for many years, in the establishment of regional research centres in fish farming and design and build hatcheries in many places. The FAO has held a number of international seminars and conferences within the past ten years to promote and disseminate technical information on it.
There are also voluntary groups and enthusiastic organisations around the region especially the Fish Farming Development Group (FFDG) based in Britain and the US Peace Corps who are actively involved in fish farming. The Biriwa Technical & Vocational Institute is set to become a major aquaculture centre in Africa since the village Biriwa has its own traditional fishing community and practices where real practical experiences in deep-sea fishing and processing can go side by side with fish farming education.
Established fish breeders always aim to create 'fish nurseries' which copiously breed young species with which to supply stocks or populating other farms or ponds or lagoons. From nursery transplants, large mature edible stocks are grown using specially formulated feeds. Thus a fish farm may consist of nursery, fattening and maturing units. The beginner is how- ever always beset with certain logistical problems which include the building and construction of the ponds, the identifi- cation of suitable species for breeding, the simulation of an aquatic environment with regard to such factors as water temperature, freshness or salinity and water plants to balance the ecology.
The Ghana Institute of Aquatic Biology (IAB) has pioneered the scientific aspects of fishing farming in Ghana through workshops and demonstrations. The IAB has four fish nurseries and 20 experi- mental farms at Akosombo which have become the training centre for prospective fish farmers. Among the courses taken regularly there are: Fish adaptation to captivity; growth production; hybridisation; production of rare species such as shellfish, prawns, shrimps etc.
According to a Senior Research Officer in charge of one of the Akosombo experi- mental farms, the training courses are meant to make fish farmers aware of the rudiments of fish farming and afford them better guidance to enable them to main- tain their fish farms. The official revealed that the Tilapia is the most popular successfully bred species of fish in fresh- water farms because of their high rate of multiplication and survival so much that ponds soon get overcrowded. He ex- plained that the problem of overcrowding can be overcome by the use of twin ponds inter-connected with canals and sluice gates, so that fishes can be directed to spare ponds.
He added that with time, novel techniques of breeding local species of aquatic creatures will become a feature of the industry, citing for example the Sumanko Farms, 95km north-east of Accra, where 'Monitors', aquatic reptiles which look like giant lizards, are being bred so suc- cessfully that the local populations have created new diets and recipes and dishes.
