Fish farming Fish farming aquaculture is the farming

Fish farming • Fish farming (aquaculture) is the farming of aquatic organism such as fish, mollusks, crustaceans and aquatic plants. • It involves certain activities such as stocking, feeding and protection from predators in the rearing process to enhance production. • Some terminologies used in fish farming: 1. Fry: a less matured stage of fish growth, usually after the yolk has been absorbed by the growing fish. 2. Fingerling: An advanced stage of fish fry, usually used for stocking fish pond 3. Fish seed: This is the young fish earmarked for introduction into the pond. A fry or a fingerling is a fish seed once it is meant for stocking. 4. Stocking: This is the introduction or planting of fish seed into the pond for rearing. 5. Wild fish: This is the fish that is not grown through the culture effort of man.

FISH FARMING SYSTEMS • In fish farming, fishes are confined in enclosures (ponds or tanks) and the farmer takes control of their management. • Fish farming practices range from extensive or subsistence to semi intensive and the intensive systems. • Extensive system Cultured organisms are collected from the wild and kept at low diversities. They are not actually fed but the culture media may be fertilized to enhance the production of natural food. • • Semi Intensive system • Cultured organisms are kept at higher diversities, than in extensive system. Agricultural by products such as poultry droppings are fed as supplementary feed and the culture media are usually fertilized to enhance natural food production. • • Intensive system Cultured organisms are produced in specifically designed hatcheries, kept at high densities and fed several times per day on compounded feed.

Factors to be considered in establishing a fish farm • The establishment of a farm depends on the following factors • 1. Location of the farm site: The farmer choosing a site to locate a fish farm must take the following into consideration: • Size of the land that is available version the size of land required for production • The topography of the land must not be too sloppy but rather relatively flat. • Accessibility: The farm must be accessible by road, not rocky and free of too many large trees. • Soil type: site must have 10 -20% clay for water retention and easy compaction. • 2. Quality and quantity of available water • Water must be available in desired quality for production throughout the year. The physical and chemical properties of water must be known by water analysis to establish their suitability for fish culturing. Parameters to be tested include the p. H, dissolved solids, dissolved oxygen and turbidity. Water for fish culture must be free from pollutions.

Factors to be considered in establishing a fish farm (cont’d) 3. Types of ponds and designs: The type of ponds to be constructed will be determined by the topography of the area and available resources. However, in planning, the following factors must be considered. • Size and shape of the pond • Water supply and drainage • Water depth in the pond 4. Type and ultimate size of fish to be cultivated: The carrying capacity per unit area varies with species cultured. The carrying capacity per unit area can be increased by modification of the water system e. g. recirculatory water system. 5. Available resources and scale of operation: Type of ponds to be constructed depends on the available resources and facilities as well as the scale of operation. Continuous production however will require more elaborate gadgets such as concrete tanks, pumps and pipes, etc. Seasonal production will thrive well in areas with abundant rainfall and good soil properties.

Topical issues in fish farming • Pond construction? • Feeding? • Sorting? • Theft/erosion? • Value addition? • Marketing? • Integrated farming?