LITERATURE REVIEW
2.1 World Aquaculture and Capture Production
Aquaculture and capture fisheries supplied about 142 million tons of fish across the world in 2008, providing an estimated apparent per capita supply of about 17kg (live weight equivalent), with aquaculture accounting for 46 percent of the total food fish supply (Food and Agriculture Organization, 2010). Aquaculture has mainly been a developing world activity, particularly on the Asian continent. Asia accounts for 87% of the world aquaculture production by weight, while China alone is responsible for about 68% of the global aquaculture production. Also, Southeast Asia and India were responsible for about 15% of aquaculture production in 1997 (Delgado et al., 2003). According to United Nations Food and Agriculture Organization (2010), aquaculture continues to be the fastest-growing animal-food-producing sector and to outpace population growth, with per capita supply from aquaculture increasing from 0.7kg in 1970 to 7.8kg in 2008 and an average annual growth rate of 6.6 percent. While production of fish from aquaculture was less than one million ton per year in the early 1950s, production was 52.5 million tons in 2008, with a value of US$ 98.4 billion.
World aquaculture is mainly dominated by the Asia-pacific region, which accounts for 89 percent of production in terms of quantity and 79 percent in terms of value. This dominance is as a result of China‟s immense production, which accounts for 62 percent of the global production in terms of quantity and 51 percent of the global value. The Caribbean and Latin America showed the highest average annual growth in the period 1970-2008 (21.1 percent), followed by the Near East (14.1 percent) and Africa (12.6 percent). In Europe and North America, the average annual growth in aquaculture production has reduced significantly to 1.7 percent and 1.2 percent respectively (FAO, 2010).
The fish sector is a viable source of income and livelihood for millions of people around the world. Employment in aquaculture and fisheries has grown significantly in the last thirty years, with an average rate of increase of 3.6 percent per year since 1980. It is estimated that in 2008, 44.9 million people were directly engaged, full time or more frequently, part time in capture fisheries or in aquaculture and at least 12 percent of these were women. This figure represents a 167 percent increase compared with the
16.7 million people in 1980. It has also been estimated that for each person employed in aquaculture production and capture fisheries, about three jobs are produced in secondary activities, including post-harvest for a total of more than 180 million jobs in the whole of fish industry. On the average, each jobholder provides for three dependants. Thus, the primary and secondary sectors support the livelihoods of a total of about 540 million people, or 8.0 percent of the world population (FAO, 2010).
On the African continent, more than 10 million people rely on fisheries as a vital entrepreneurial activity. Over 2.5 million fishers make business opportunities. For most of them, the fishing industry is a good avenue for generating income. Of Africa‟s more than 800 million people over 200 million are regular fish eaters. To them, fish is an essential part of their nutrition, accounting on the average for 22% of their animal protein intake reaching up to 70% in some countries (World Fish Centre, 2005).
In Nigeria, the actual total domestic fish production in 2005 was about 579,500 metric tons. Annual national demand stands at about 1.5 million metric tons leaving a deficit of about 920,500 metric tons (Adamu, 2007). According to Omitoyin (2007), Nigeria is blessed with suitable land where both freshwater, brackish and marine fish species can be cultured. If this available land is put into proper use, fish production will increase significantly. Table 2.1 shows fisheries and aquaculture production and utilization around the world from year 2007 to 2012.
Thomas (1994) stated that intensification of fish production from pools in African floodplain, through water management, fertilization and stocking with fingerlings, was technically a success. He found out that fish production per hectare was 171% greater in managed ponds compared with unmanaged ponds and in terms of income derived from labour inputs for pond management, the returns per man hour compared favourably to alternative activities.
Satia (1990) observed that since 1984, there has been a surge of interest in large scale commercial fish farms owned and/or operated by a new breed of influential, wealthy and sometimes knowledgeable or skilled Nigerians, whose interest in the subsector has been kindled by various administration on one hand and by a series of reforms enacted by Government in favour of agricultural development after the oil boom era, on the other hand. In the private sector there were about 2000 rural fish ponds, 3000 homestead ponds and over 50 commercial farms. In the public sector, there were more than 30 fish seed production units and hatcheries, a large pool of trained manpower, as well as training and research facilities for aquaculture. However, most public sector units were operating below capacity as a result of insufficient and unreliable release of funds, inadequate input supplies, management problems and insufficient staff motivation. Progress in the private sector on the other hand, was hampered by inadequate supply of quality fish seed and feed, painful procedures to have access to land and credit facilities.
Table 2.1: World fisheries and aquaculture production and utilization
Production
2007
2008
2009
2010
2011
2012
Capture (million tons)
Inland
10.1
10.3
10.5
11.3
11.1
11.6
Marine
80.7
79.9
79.6
77.8
82.6
79.7
Total capture
90.8
90.2
90.1
89.1
93.7
91.3
Aquaculture (million tons)
Inland
29.9
32.4
34.3
36.8
38.7
41.9
Marine
20.0
20.5
21.4
22.3
23.3
24.7
Total aquaculture
49.9
52.9
55.7
59.1
62.0
66.6
Total World Fisheries
Utilization
140.7
143.1
145.8
148.2
155.7
157.9
Human consumption (million tons)
117.3
120.9
123.7
128.2
131.2
136.2
Non-food uses (million tons)
23.4
22.2
22.1
19.9
24.5
21.7
World population (billions)
6.7
6.8
6.8
6.9
7.0
7.1
Per capita food fish supply (kg)
17.6
17.9
18.1
18.5
18.7
19.2
Source: FAO, 2014.
Fish Farming and Food Security
Food security as defined by FAO (1996) is a condition whereby people everywhere irrespective of their gender, ethnicity, religious or political affiliation, age, social status etc have physical and economic access to safe, sufficient and nutritious food to meet their dietary needs and food preferences for an active and healthy life. Fish farming can be a major player in ensuring food security locally by providing food directly to the producer or to the immediate community especially in many areas of Anambra state and in Nigeria as a whole. This contribution can also be indirect; as an economic activity which is reliable and regular, especially in comparison with traditional capture fisheries, and as an option for diversification into new opportunities. In many areas of Anambra State, the dependence on fish is high. Fish farming or aquaculture provides a direct supply of fish, either for consumption by fish farmers and their family members or members of the society buying fish from fish farmers for their dietary needs. Fish is one of the cheapest protein sources available in developing Countries and they are processed locally and transported over long distances, providing a cheap protein source for the poor and the middle income earners thereby enriching their diets. With the ever increasing population of Nigeria, the demand for fish also increases.
Of all the different food production supply systems around the world, fish farming or aquaculture is seen as an essential domestic provider of the high premium animal protein and other vital nutrients generally at affordable prices to the poor segments of the society (Tacon, 2001). Increased fish production will help in combating hunger and malnutrition, which remain one of the most devastating problems facing the majority of the poor and the needy in the society. World Health Organization (2000) reported that nearly 30% of humanity, including infants, children, adolescent, adults and the elderly in developing Countries are currently suffering from one or more of the multiple forms of malnutrition, abject poverty and food insecurity. With the decline in capture fisheries as a result of factors such as climate change, oil spillage etc, there is an urgent need to look in the direction of fish farming to meet the ever-increasing demand for fish while recognizing the contribution of fish farming to food security, it is also important to state that it provides a new livelihood of higher income for those who engage in it.
Nutritional benefits of fish
In many developing Countries like Nigeria, fish accounts for a high proportion of animal protein intake of the population. Fagbenro (2002) reported that fish provide at least 40% of dietary animal protein of people living in the developing world. Fish also supply highly digestible protein and is a rich source of minerals, fatty acids and water soluble vitamins. The high value of nutrition in fish is particularly important for lower income groups that might otherwise depend on a cereal-based food to meet their dietary needs. Cereal grains are usually low in lysine and sulphur-containing amino acids; so by supplementing their diets with fish significantly raises the biological value of the diet. According to FAO (2006), fishery products like many other animal products contain nitrogenous compounds, lipids, carbohydrates, minerals and vitamins. Table 2.2 shows the nutrients composition of catfish as an example of nutrient in fishery products consumed by humans as food.
Table 2.2: Nutritional value of catfish
Nutrient
Quantities
Unit
Protein
18.20
g
Iron
0.82
mg
Calcium
9.00
mg
Iodine
0.10
mg
Potassium
321.00
mg
Vitamin A
0.02
mg
Vitamin B2
0.10
mg
Vitamin B6
0.20
mg
Source: United States Department of Agriculture, 2002.
Nutritionally, fish is therefore an extremely essential source of protein and micro nutrients for millions of people in Africa in general but for Nigerians specifically and in
Anambra state in particular. Fresh but more often smoked, dried or even processed in powdered form, fish is a critical source of protein and micro-nutrients for many isolated communities in rural areas. Fish may also be the sole affordable or accessible source of protein for poor households in rural, peri-urban and urban areas. Of Africa‟s more than 800 million people, more than 200 million eat fish regularly. To them fish is an important part of their diet, accounting on the average for 22% of their animal protein intake reaching up to 70% in some Countries (World Fish Centre, 2005).
In human nutrition, fatty acids such as linolenic and linoleic acids are essential for preventing skin diseases and considered very important as they cannot be produced by humans. However, fish oils contain vital polyunsaturated fatty acids which act in the same way as linoleic and linolenic acids. Members of the linolenic acid (fist double bond in the third position, on w-3 counted from the terminal methyl group) have neurological benefits in growing children. One of these fatty acids, eicosapentaenoic acid (c20:5 w3) has attracted considerable attention since Danish scientists found a significant presence of it in the diet of a group of Greenland Eskimos who proved virtually free from arteriosclerosis. Studies in the United Kingdom and elsewhere have documented that eicosapentaenoic acid in the blood is an extremely potent anti- thrombotic factor (Huss, 1995). Fish also contains Omega III fatty acids that are known to reduce cardiovascular diseases, hypertension and arteriosclerosis, thus becoming a preferred source of animal protein for those nearing 50 years of age and above. Omega III fatty acids are also known to enhance good brain cell development in developing foetus, (thus, a vital diet for pregnant women) and intelligent Quotient (IQ) in developing children (Federal Department of Fisheries, 2005). From the foregoing, it is evident that fish is crucial to the economy and health of the nation.
Role of Fish Farming in Achieving Millennium Development Goals Millennium Development Goals (MDGs) are a set of eight goals set by the United Nations (UN) and these goals are targeted at reducing poverty globally. When the UN Millennium Development Goals were first announced in September of 2000, a deadline of 2015 was set to halve global poverty. At that time, 15 years seemed long enough. Today, we are barely 1 year away from the deadline.
Eradication of extreme poverty and hunger is the first goal of the MDGs. The World Bank (2001) put poverty index (Poverty Line Value) at $1 per person per day for extreme poverty and $2 per person per day as general poverty line. For many people in the developed world $1 is pocket change, perhaps used towards buying a cup of coffee or a lottery ticket. Yet for millions of people living in poverty in Nigeria, $1 is more than they have to spend each day on food, shelter, clothing, health and education; it‟s the mark of absolute poverty. MDGs report of 2009 released by the UN Secretary- General, Ban Ki-moon, indicates that Asia has made gains that put it on track to achieve most of the eight goals but Africa including Nigeria is falling behind. In spite of this bleak report, all hope is not lost as fish farming, a powerful blue revolution, offers a huge ray of hope. Money realized from selling fish provides an important contribution to household spending. Also, government revenue from industrial or large scale fish farming can be used to support economic growth and can be specifically targeted towards pro-poor investments which will go a long way in reducing extreme hunger and poverty. According to FAO (2010), it‟s estimated that for each person employed in aquaculture production, about three jobs are produced in secondary activities, including post-harvest, for a total of more than 180 million jobs in the whole of fish industry. On the average, each jobholder provides for three dependants. Contribution of aquaculture
industry is not only limited to provision of job opportunities to rural, peri-urban and urban population. It also provides a new livelihood of higher income other than other agricultural activities in many countries. For example, economic return from pond fish culture is usually 4 6 times of the return to the same area of crops in China, which significantly contributes to poverty alleviation.
Achieving universal primary education is goal number 2 of the MDGs. Education, the development of the human mind cannot be achieved when there‟s no financial support either from government or home. Household income supported by money realized from fish farming will go a long way in promoting children‟s education. The nutritional benefits from fish also help children‟s development and learning abilities (Fisheries Management Science Programme, 2012). So, fish farming has a greater role to play in achieving primary education not only in Anambra State but throughout the federation.
Gender equality and women empowerment has been an issue of interest all over the world. It won‟t be surprising to see it as goal number three of the MDGs (Millennium Development Goals). Fish farming has a key role to play here. For women in particular, fish processing and trading provide a very important livelihood support in Anambra state and other parts of the Country. Because fish processing and trading do not require strong physical strength and can be undertaken by unskilled labour, they provide opportunities for a large number of women, many from the lowest strata of the society. For many of these women who are heads of households, fish therefore represent the primary and sometimes, the only source of income. Fish farming can actually help in empowering women (Fisheries Management Science Programme, 2012).
Fish is a vital component of diet in many parts of the world including Nigeria and Anambra state in particular, complementing the carbohydrate-based diet of the poor; and providing an important part of children‟s nutrition which helps their development. Regular eating of fish reduces malnutrition associated with a lot of infant deaths. In a developing Country like Nigeria, staples such as rice, maize and cassava make up the bulk of food consumed by the people and most of these staples are either lacking in essential nutrients or contain essential nutrients in minute quantity. Fish is an alternative source for the supply of these vital nutrients particularly fatty acids that are important for the development of the brain and the body. According to World Health Organization (2000) nearly 30% of humanity, including infants, children, adolescent, adults and elderly within the developing Countries are currently suffering from one or more of the multiple forms of malnutrition, food insecurity and abject poverty. Fish farming, therefore, can play an effective role in reducing infant mortality which is goal number four of the MDGs.
Income from fish farming and nutritional benefits from fish can improve maternal health and these will go a long way in reducing the menace of maternal death not only in Anambra state but throughout Nigeria. Fish consumption during pregnancy and lactation further improves the nutritional and health status of women, thus reducing vulnerability to diseases. Fish flesh is a valuable source of nutritive elements such as calcium, potassium, iron, phosphorus, selenium and vitamins such as A, B and D which help in promoting the health of women during pregnancy and after child birth (Ward, 1996). Fish protein is vital in improving the overall quality of a mixed diet and thereby, helps in improving maternal health.
Many lives have been lost all over the world as a result of the menace of Human Immuno-deficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS), malaria and other diseases. Many orphans have been made as a result of HIV/AIDS and malaria is believed to be one of the biggest killers in the world. In an attempt to stem this dangerous tide, the United Nations has made fighting or combating HIV/AIDS, malaria and other diseases a top most priority. This is goal number 6 of the MDGs. According to Ward (1996), fish has been shown to contain a combination of proteins, vitamins and minerals that help to fortify affected persons against vulnerability to secondary diseases (opportunistic infections) since improved nutrition increases the effectiveness of anti-retroviral drugs.
Inoni (2007) observed that there is a decline in yield of natural fish stocks which is an indicator that fish stocks have reached the point of maximum sustainability yield since the number of catch from capture fisheries is declining, it‟s only proper to consider an eco-friendly agricultural system like fish farming to meet the increasing demand for animal protein. The sustainability of the environment is very important in determining the success of any farming venture. The Broundtland Commission (World Commission on Environment and Development, 1987) defined sustainable development as the ability to meet the needs of the present without compromising the ability of the future generation to meet their own needs. Coastal resources depletion and land degradation are factors that lead to poverty since continuous deterioration of coastal resources results in reduced fish catch and therefore, bring about reduction in fish protein consumption and income of fishers, thus increasing poverty level and perpetuation of its vicious cycle. These and other reasons call for serious attention to be focused on environmentally friendly agriculture system like fish farming. Enlightening, encouraging and empowering people to practice fish farming will minimize the negative impacts of overfishing and associated environmental problems thereby promoting environmental sustainability which is the seventh goal of the MDGs.
Fish is one of the most highly traded food commodities in the world. Over 40% of all fish cross international borders (World Fish Centre, 2005). Delgado et al. (2003) stated that developing countries have more than doubled total fish production since 1973. The shift in fish farming in particular, especially in Thailand and Malaysia has created a major source of export revenue. Developing nations are being transformed from the status of net importers of fisheries products to that of large net exporters. FAO (2002) reported that fisheries products represented a major source of export revenue for developing Countries, amounting to over US$20 billion per annum in the late 1990s. The fishery trade is particularly important for developing nations. FAO (2014) reported that fishery trade in 2012 represented 10% of total agricultural exports and 1% of world merchandise trade in value terms. Import and export of fish between Countries promote partnership for global development which is goal eight of the MDGs.
Fish Culture Systems
Globally, different techniques of fish culture have been developed from time to time in order to obtain maximum yield of fish. According to Gupta and Gupta (2006), culture practices may be on the basis of habitat (kind of water), economic or commercial considerations, one (monoculture) or multiple organisms (polyculture), operative design of the culturing sites etc.
Economic consideration in fish culture system
System of culturing fishes based on economic or commercial consideration can be grouped into three namely; extensive, intensive and semi-intensive system (Gupta and Gupta, 2006).
Extensive system: - It‟s the least managed culture practice where there is a modest yield. It adopts the traditional technique of culture which depends on natural productivity of the pond. Some fish obtain their food exclusively from plankton e.g. Silver carp. Others such as Tilapia feed on plankton and also on bottom materials. Common carp is an efficient bottom feeder while others like grass carp consume large quantities of higher plants. Such fishes have been cultured without artificial feed but with pond fertilization.
Intensive system: - This system involves the adoption of full culture techniques including maximum feeding, water quality control, scientific pond design, full measure of stock manipulation, disease control, pond fertilization, scientific harvesting etc. With this system, maximum yield per unit of space and effort is a primary concern and highly nutritional artificial feed are used. The investment is quite huge i.e. it‟s characterized by high level of inputs and high rate of production. Examples are fish culture in spring-fed raceways, culture in recirculation system and net pens in the sea.
Semi-intensive system: - This system of farming takes full advantage of the natural productivity of the aquatic environment and as well as using prepared feed as supplements to increase yield further. The additional yield of fish resulting from additional feeding is profitable.
Design consideration in fish culture system
Culture practices also vary in magnitude and intensity, ranging from homestead (backyard) units to large scale commercial ventures. They include culture in raceway farms, culture in cage farm, pond culture, flow-through culture, culture in tank etc (Gupta and Gupta, 2006).
Raceway farms: - Raceway farms are farms designed or constructed in a way to have regular and abundant flow of good quality and well-oxygenated water. The main sources of water are springs, streams, deep wells or reservoirs. The raceway may be
„earthen‟ or made of concrete or cement blocks. The earthen raceways can be lined with plastic material to reduce loss of water through seepage. Raceway farms may be in series or parallel design and the design of a raceway requires the use of the contour of the land. Generally, a slope of 1-2% is suggested. One section of a raceway can be about 30m long, 2.5-3.0m wide at the bottom and 1.0-2.0m deep. A raceway farm may consist of 15 to 20 or more segments. All segments should be straight so as to ensure uniform flow of water and each segment should have a separate feeder channel. Therefore, it is important to have water control structures or weirs to regulate the flow and depth of water. Such structures are reinforced concrete, concrete blocks, culverts and metal sheet. In order to ensure regular water supply to raceway farms, a storage reservoir proves to be beneficial, if it is constructed near the mouth or beginning of a raceway system. Similarly, a suitable suction device is important for cleaning raceway bottoms.
Cage farm: - This culture practice of raising fish is particularly unique in that the fish to be cultured are kept in cages of metal mesh, nylon or bamboo mesh, left in the
flowing water. Generally, floating-type of cages are used but submersible and rigid- walled cages are also used. The floating type consists of a floating unit in the form of a framework and a flexible mesh-net cage-bag suspended under it. The floating unit may consist of empty barrels and Styrofoam polythene pipes. Nylon is commonly used for the net but woven split bamboo or weld-mesh can also be used. Cages of underwater net volume of 200 and 500m3 are the most preferred ones. It‟s always advisable to have double netting, the outer one serving as a predator net to protect the inner one where the fish stock is kept. When welded, tubular metal or Poly Vinyl Chloride or fiberglass tubing is used for the framework, there is greater flexibility in shapes and sizes of the cages. There are seven ways of arranging the cages in a cage farm. It is advisable to moor cages to a jetty with easy approach, in order to facilitate work and reduce labour costs. Depending on the local conditions, the cage farms may also be installed farther away from the coast and there will be a floating house for the caretaker and a boat to have an access to the farm.
Pond farms: Ponds are bodies of quiet standing waters with only slight wind action. Most ponds used for fish culture are man-made. Ponds are of different categories e.g. embankment and excavated ponds. Embankment ponds are formed by building up a dam, dike or similar above ground structure to impound water. These are the most common ponds used for fish culture because they can be constructed in a great range or topographic conditions. Excavated ponds on the other hand, are ponds constructed by removing soil from an area to form a hole that is then filled with water. They are constructed in an area with a relatively flat topography and removal of water from such ponds is usually by pumping. The ponds may be rained and may have inlet and outlet systems for water supply. The water supply may be from a stream or from underground
wells. The water retaining ability of the pond depends on soil composition of pond bottom and subsoil water level. The natural biological productivity of such ponds depends on soil and water qualities. The carrying capacity of still-water ponds is enhanced by manuring/fertilization and ensuring water quality control.
Flow-through farms: - The real breakthrough in fish culture came with the construction of the flow-through system after realization that not the size of the water area but the quantity of water flowing through limited the yield. Fish culture in flow- through system is a type of intensive culture where the fishes are densely stocked in a long and narrow tank in which there is continuous and abundant flow of water. The fishes are stocked on the basis of the volume of inflowing water and they are fed pelletized and properly formulated feed. A continuous water flow ensures sufficient oxygen supply and flushes away metabolic wastes. The flow-through culture practice relies upon abundant and continuous water supply. The most intensive common carp production rate of 980 metric tons/hectare has been achieved at the Tanaka Running- water fish farm in Japan where there‟s plenty supply of running water of high dissolved oxygen content.
Tank farms: - As against the ponds, the tanks are made of concrete, fiberglass, marine plywood, metal or other hard substances. As regards their shape, the tank farms may be circular or rectangular in design.
Concrete cement tanks may be circular or rectangular. Water inlets are arranged on the wall in order to ensure proper circulation of water. Circular tanks used for catfish culture range up to 6m in diameter and 0.8m in depth, with a gradient of approximately 5cm from the circumference to the central drain. Rectangular tanks may be 8.0m long, 1.0m wide and 75cm deep. The bottom may be slopy towards one end or towards the middle for better cleaning and draining.
Fiberglass tanks are generally circular in outline and „fiberglass‟ is a popular material for tank construction as it is light and strong.
Fish culture management
Fish growth rate and yields from fish farming enclosures can be immensely increased through emphasizing adequate management techniques, steps or procedure that enhances maximum productivity. This involves manipulating a complex of physical, biological, chemical and environmental factors that promote high stocking rate, growth rate, survival rate, good pond structure and water quality (National Special Programme for Food Security, 2005). National Special Programme for Food Security also identified the following ten commandments of fish culture management for a successful fish farming enterprise:
Stock healthy and disease-free fingerlings, preferably obtained from fish hatcheries and not from the wild.
Avoid overcrowding, and stock correct number of fingerlings per unit area.
Maintain good water level and quality always.
Watch out for fish enemies (including human poachers) and eliminate or control undesirable and unwanted organisms inside and around the pond area.
Feed fish regularly from the same feeding spot by gradual broadcast.
Avoid excessive feeding in over to prevent pond fouling and pollution.
Replenish water if water colour is too deep, green or when fish begin to gather at the surface to gulp for air.
Watch fish behavior for any abnormalities and immediately remove diseased, dead or dying fish (or any other dead animal found in the pond area).
Maintain pond structures. Routinely check for blockages and damages and repair pond walls, pond bottom, screens, inlet and outlet water supply structures.
Keep accurate records of fish farming activities.
Species of Fish and Selection
To select an appropriate species of fish for culturing, consideration of farmer‟s knowledge; and previous experiences in fish farming are important. The availability and relatively easy access to seed stocks of appropriate species, when required, is another important consideration. Desirable characteristics for cultured species according to Australian Centre for International Agricultural Research (2006) include:
Fast growing and efficient converters of food enabling them to reach marketable size within a short period of time.
Market demand for that particular species because the ultimate goal of fish farming enterprise is to make profit.
Acceptance as food fish to the surrounding communities; this matters significantly if the cultured fish is different from the conventional food types of that particular geographical region, and if the consumers do not know how to process or cook the species in a suitable way.
Ability to co-exist with other species in a water body in order to maximize the use of available space and productivity; this is commonly known as polyculture. Since there are various forms of natural food items within a water body, different species consuming different food items can be farmed together without any conceivable competition for food and space.
Ability to depend on the available natural food resources within the water body in a short food chain i.e. fish species that depend on phytoplankton, zooplankton and detrital aggregates should be stocked rather than carnivorous species.
Fish seeds can be obtained from fish farms. The average production cycle form rearing egg to fingerling stage (1-5gram) requires six to eight weeks, while for table-size fish; it ranges from 5-9 months (600-1000gram) depending on the type of fish and culture practices. Ajana (1995) asserted that culturable fish species in Anambra state and Nigeria in particular are: Clarias gariepinus, Gymnarchus niloticus, Lates niloticus, Cyprinus carpio, Chana obscura, Tilapia niloticus, Tilapia galilea, Tilapia zili, Tilapia melanopleura, Labeo coubie, Bargus bagad, Clarotes laticeps, Citharinus spp.
Overview of Fish Production in Nigeria
In Nigeria, fish amounts to about one fifth of total animal protein supply and this will rise in about five folds over the next forty years from 20 million metric tons to 98 million metric tons by the year 2010 (FAO, 2000). Ajana (2002) reported that the average annual demand for fish in Nigeria between 1995 and 2000 was established at
1.22 million metric tons and that this might increase to about 1.425 million metric tons by the year 2005. Adamu (2007) reported that the actual total of domestic fish production in Nigeria in 2005 was about 579,500metric tons. Nnodim (2014) reported that domestic fish production in 2014 was about 800,000 metric tons.
Akpan (1973) studied pond fish culture in Western Nigeria and discovered that pond fish culture is a viable enterprise. He stated that a well-built fish dam is a lifetime investment fully capable of paying back its fixed (investment) cost in 5 to 10 years at maximum. With adequate management, a 4-hectare pond stocked with Tilapia, was according to him, capable of yielding a gross margin of N380 as against N850 when cultured with carp.
Esobhawan (1986) examined resource use efficiency in 47 fish farms in Anambra and Cross River States. The result of the study showed that resources were efficiently utilised in the two States. The computed elasticity of fish production showed that the fish farmers were operating in stage II of production, which is the rational stage of production. It was also observed that the fish farms enjoyed increasing returns to scale. The study proceeded to identify scarcity of feeds, inadequate training and insufficient supply of fingerlings as the main constraints hampering the development of fish farm in the two States.
Agbebi (2011) studied the impact of fish farming on poverty alleviation in Ekiti State, South-West, Nigeria. The study examined the level of fish production, socio-economic characteristics of fish farmers, fish culture management system and the contribution of fish farming to the livelihood of the poor through food supply, employment and trade. The result of the study indicated that a larger percentage of the fish farms were owned by individuals and average farm size of 28.5m2 was recorded while the gross margin analysis revealed a profit of N63,055.05. The study went further to identify management lapses, disease outbreak, predators, poaching as factors that contributed to low profitability of fish farming. The study concluded by suggesting that there is need to raise awareness of huge potential economic contribution of fish farming as it is currently unappreciated and ignored by policy makers and development professionals. Until fish farming is given the right attention it deserves, only then will its potential to
contribute towards poverty alleviation, entrepreneurship, self sufficiency in fish production and increased animal protein have brighter prospects of being realised.
From the above reviews of related studies, it is clearly seen that some works had been done on fish farming but not specifically on Akure South and Owo Local Government Areas which this study intends to do by carrying out an economic analysis of fish farming and its contributions to household poverty alleviation in the two Local Government Areas.
Problems militating against Fish Farming in Nigeria
In contrast to the rest of the world, per capita fish consumption in sub-Saharan Africa including Nigeria has declined to almost half of the global average and despite suitable natural conditions; aquaculture provides only 2 percent of the region‟s supply of fish and little economic growth, employment and foreign exchange (World Bank, 2006). Past aquaculture development efforts have largely failed due to weak institutions, poor access to finance and a heavy reliance on failing government extension services and seed production. The focus on subsistence aquaculture may also have been misguided, as it often lacks the driving force of market demand and impetus provided by commercial reality.
The use of many small production units, mainly earthen ponds of less than 0.04 hectare in size, characterizes fish farming in Nigeria and Anambra State in particular. Other notable constraints to fish farming in the Country are inadequate supply of high quality formulated fish feeds particularly for fingerlings and brood stock, inadequate credit facility, non availability of improved species of fingerlings, the use of rudimentary technologies, difficulty in accessing land for fish production and inadequate extension services (Tobor,1985). Also, fish farmers get little return for their efforts due to the activities of middlemen. Hence, there are low returns in terms of fish farm income to them. This, therefore, contributes to some forms of poverty among the fish farmers. Esobhawan (1986) identified scarcity of feeds, inadequate training and insufficient supply of fingerlings as the main constraints hampering the development of fish farming in Anambra State.
Poverty Profile of Nigeria
In spite of the fact that the Nigerian economy is paradoxically growing, the proportion of Nigerians living in poverty is increasing every year. The proportion of the population living below the poverty line increased significantly from 1980 to 2010 (National Bureau of Statistics, 2012) as shown in Table 2.3. NBS (2012) also reported that in terms of absolute poverty, 45.7% of Anambra State population are categorized as poor while 54.3% are classified as non poor.
Table 2. 3: Relative poverty headcount from 1980-2010
Year
Poverty Incidence (%)
Estimated Population
(Million)
Population in poverty
(Million)
1980
27.2
65.0
17.1
1985
46.3
75.0
34.7
1992
42.7
91.5
39.2
1996
65.6
102.3
67.1
2004
54.4
126.3
68.7
2010
69.0
163.0
112.5
Source: National Bureau of Statistics, 2012.
Figure 2.1 shows the absolute poverty measure in Nigeria in 2010.
Figure 2.1. Map of Nigeria: Absolute Poverty Measure in 2010.
Source: National Bureau of Statistics, 2012.