Fish production practices of smallholder farmers in western Kenya

Simion K Omasaki^1,4, Harrison Charo-Karisa³ and Isaac S Kosgey^1,2

¹ Department of Animal Sciences, Egerton University, P.O. Box 536, Egerton-20115, Kenya
isaac_kosgey@yahoo.co.uk   /   isaacs.kosgey@gmail.com
² Laikipia University, P.O. Box 1100-20300 Nyahururu, Kenya
³ Aquaculture Development Working Group, Kenya Marine and Fisheries Research Institute, Sagana and Nairobi Aquaculture Research Centre,
P.O. Box 58455, Nairobi-00100, Kenya
⁴ Animal Breeding and Genomics Centre, Wageningen University,
P.O. Box 338, 6700 AH, Wageningen, The Netherlands

Abstract

To be successful, initiatives to improve smallholder fish production should directly address the needs and objectives of the farmers while promoting national use of available fish genetic resources. This study aimed at providing a better understanding of smallholder fish farming systems, the fish types reared, general management, constraints and needs of fish farmers in western Kenya, and discusses their relevance to the improvement of fish farming. A cross-sectional survey employing sets of structured and semi-structured questionnaires, focused group discussions and participant observation were used to collect information from 102 farmers in three selected Counties.

On a scale of most to least important, most farmers ranked cattle as first, followed by fish, goats/ sheep, poultry and bee keeping, respectively. Fish were kept mainly for sale whenever cash was needed and for household consumption. Farmers owning Oreochromis niloticus fish were predominant (56.8%) relative to those owning mixed species (Clarias gariepinus, Oreochromis esculentus and Oreochromis variabilis) at 37.3%. Some farmers (5.9%) had no information on the specific species they owned and confused the other Tilapiines with O. niloticus. A range of traits; mothering ability, growth rate, size, survival, hatchability, feed conversion efficiency, adaptability and resistance to parasites were considered equally important and were ranked very highly by the fish farmers. Growth and size ranked as the most important traits. Most farmers purchased their foundation (66.7%) and replacement (61.8%) stocks. No farmer across the Counties reported any incidence of disease outbreak. However, about 93.1% of the farmers reported a strong parasite problem. Predators also seriously affected farmers, where birds (88.2%) and frogs (71.6%) had a major effect. Lack of feeds, finances, skills and fingerlings were ranked, in ascending order, as the most important problems. Generally, initiatives to improve management practices are an overriding priority in smallholder fish production. Improved management will lead to increased productivity in the short-term and foster participation of farmers in the development of long-term fish improvement strategies.

Key words: aquaculture, production system, Tilapia

Introduction

The increasing human population pressure, and the ensuing land demarcation in Kenya have stimulated use of alternative farming methods and animal species in rural development efforts, which were previously ignored (MoLFD 2007). With this, the role of aquaculture in food production, economic development and food security is increasingly becoming important in the country and the whole world. It is evident that aquaculture is currently the fastest growing segment of food production in the world. According to FAO (2012), capture fisheries and aquaculture supplied the world with about 148 million tonnes of fish in the year 2010, of which about 128 million tonnes was utilized as food for people, and preliminary data for 2011 indicate increased production of 154 million tonnes, of which 131 million tonnes was destined as food. With sustained growth in fish production and improved distribution channels, world fish food supply has grown dramatically in the last five decades, with an average growth rate of 3.2 percent per year in the period 1961–2009, outpacing the increase of 1.7 percent per year in the world’s population (FAO 2012). However, fish consumption in Africa is still lowest relative to other parts of the world.

From the foregoing, aquaculture holds promise to help provide a growing human population with food as many of the world’s capture fisheries have reached their biological limits of production or have been depleted through over-fishing and habitat degradation (United Nations 2005; MoLFD 2007; FAO 2012). To meet the increased demand for food, fish and aquaculture production should increase by 50 million metric tons by 2050 (Tacon and Forster 2001), especially from smallholder production.

Smallholder farmers are found mainly in the medium to high potential areas, and tend to farm for family needs rather than purely on economic objectives (Rege 1994; Kosgey 2004). Fish production and associated technologies are, therefore, preferred as a fast means of improving food production and diet quality of smallholder farmers and, quickly their economic status (MoLFD 2007). During the early stages of development of aquaculture, rapid advances can be made in production volumes and efficiency with relatively simple and cost effective improvements, and innovations in general husbandry, nutrition and health management (Mair 2007). Aquaculture has huge potential for expansion in Kenya but fish-farming systems are underdeveloped and are practiced at low levels of intensification. Factors that favour the rearing of fish include ability to thrive well across agro-ecological zones, as reflected by the degree of their adaptation (i.e., survival under environmental stresses like diseases, parasites and high temperatures), functional contribution (i.e., meat) and socio-economic relevance (i.e., security and income generation). Other attributes of fish are shorter generation intervals, lower investment, feed and labour requirements (MoLFD 2007).

Fish production practices in Kenya, from the farmer’s perspective, have not been optimally understood and practiced, a situation that limits interventions for improvement of production. The current study aimed at providing better understanding of fish farming systems, fish species reared and production practices in western Kenya. This is important for identification of constraints, and opportunities for guidance and targeting of expansion of fish farming in the country and other areas with similar production circumstances.

Materials and methods

Sampling and interviews

Data for the study was collected in a cross-sectional survey from smallholder farmers in three Counties in western Kenya, namely, Kakamega, Kisii and Siaya, all lying between medium to high potential areas with average annual rainfall between 800 and 1600mm, and mean monthly temperatures between 19 and 30°C (MoLFD 2007). The target areas in the three Counties were selected in consultation with officers from the Ministry of Fisheries Development, Kenya Marine and Fisheries Research Institute, local community-based organizations (CBOs), and the Provincial Administration (Chiefs), who were also, interviewed using sets of pre-tested structured and semi-structured questionnaires.  A total of 102 farmers, all with fish records were interviewed. A comprehensive review of the relevant literature was also undertaken to obtain secondary information. A formal rapid field survey, including visual appraisal of the fish, was conducted using questionnaires with the specific objective of exploring the available knowledge about the type, distribution, importance, management systems and production practices of the fish species in the region. Locations with fish farmers who had kept fish and harvested at least twice were selected. After sub-dividing the target areas into clusters of 2 km radius each, individual fish farmers with records within these clusters to be interviewed were selected as available. This approach was adopted due to the scarcity of fish farmers with records.

The key considerations while interviewing the farmers included; species of fish cultured (i.e., species and culture practices), level of operation (i.e., number of ponds owned, production level, management skills and type of constraints). For each sampling site, farmers were briefed about the objective of the study before starting the interviews and data collection on the farms.

Information was collected based on the characteristics of the farms, fish types, fish production systems, management and farming support services provided by the Ministry of Agriculture/ Ministry of Livestock Development/ Non-Governmental Organizations. Visual appraisal of the fish types was undertaken for identification and corroborated with a checklist. Interviews with traders were done alongside the general survey in the three Counties to establish fish prices. The data is presented using descriptive statistics, i.e., mean, range, frequency and percentage. Chi-square was used to determine if there were significant differences or not between observations. K related sampling was used to rank animals, traits and constraints, and Pearson correlation coefficient was used to present the relationship between variables. The SPSS (Version 11.5) computer software was used to analyze the data.

Results

Fish farmer’s characteristics

There are several dimensions of socio-economic variables, but only a few indicators were used in the current study. The measure of an individual socio-economic characteristic largely depends on that individual’s age, if household provider, occupation, level of education and family size. In this study, attention was on certain variables, which were selected to determine the characteristics of the majority of the fish farmers in the study areas. These are discussed below.

Gender and age structure of the respondents

Fish farming was a predominantly an activity for older men (Table 1), an indication that most young farmers across the three Counties did not currently value fish as an important activity. Generally, the average age of male respondents was higher than that of the females, implying that cultural practices, e.g., land ownership and decision making within the family limited participation of women in fish farming. Relatively, older men engaged more in fish farming than their female counterparts.

A significant relationship existed between age of the respondent and fish yields (Table 1). This was not surprising because old aged respondents owned large numbers of family fish, while other age groups owned relatively small numbers across the three Counties. It was also evident that a significant relationship existed between fish sold and size of the pond and the yields of fish. 

Family size, education and occupation of the respondents

The mean family size for the surveyed areas comprised both males and females, an indication that a family composed of a male or female as the head of the household and children, or other relatives, or a widow with children (Table 2). Majority of the respondents had formal education and the rest none. Most of the fish farmers had attained at least primary and secondary education while the minority had attained post-secondary education. On County basis, Kakamega had the highest respondents attaining post-primary education, followed by Siaya and Kisii (Table 2).

Majority of the respondents were farmers, most of them  retired employees and, therefore, opted to practice mixed (crop-livestock) farming to sustain the nutrition of their families and as a source of cash income for other needs. A few of the respondents engaged in off-farm work (Table 2). Lack of alternative sources of income for majority of the respondents suggested strong reliance on agriculture and, consequently, fish farming is expected to expand if the constraints affecting it, as discussed in later sections of this paper, are curbed. From informal discussions, it was clear that farmers were ready to venture into fish farming if the problems affecting it were addressed.

Land size

The mean land sizes were significantly different between the Counties (P<0.05). Arable farming occupied the largest area relative to other farming activities (Table 3), while fish farming occupied the smallest area. This indicated limited land allocation for fish farming, which can be attributed to low access to extension services by farmers and, consequently, little information on the benefits of fish farming, a factor that can limit expansion of fish production.

A significant relationship existed between land size of the respondent and fish ponds owned (Tabled 3). This was not surprising because the respondents owning large land sizes had large and many fish ponds. This has an implication for the overall fish yields. Evidently, a significant relationship existed between fish ponds and arable land, forest and grazing. As farmers practiced more of arable farming, forestry and rearing other farmed animal species, less land and priority was directed to fish farming, a situation which may affect fish farming in future.

Training of fish farming

The Counties differed significantly (P<0.05) in training on fish farming (Table 4). Kakamega had majority (33.5%) of the respondents who had attended at least a course on fish farming, followed by Siaya (29.6%) and, lastly, Kisii (11.8%) (not shown in the table). This indicated that, across the Counties, 74.9% had attended a course on fish farming and 25.1% had not at all.

Most of the respondents (71.6%) learnt about fish farming from extension agents. Others learnt from other farmers (20.6%) and the minority (7.8%) from other sources like radios, television and magazines.

Purpose for keeping fish

All the respondents (100%) kept fish as an alternative source of food and for regular cash income, i.e., creation of employment opportunities. Some respondents (43%) cited utilization of wetlands as the reason for venturing into fish farming, while few reported rearing fish as a status symbol (6%).

Source of labour

The most important source of labour was the family, with some being hired (Table 5). The combination of family and hired labour was also commonly used. The major tasks were general cleaning and management of the fish ponds, predator management and harvesting of the fish.

Constraints to fish farming

Among the constraints to fish farming in the three Counties were; lack of feeds, which ranked first, followed by finance, skills and fingerlings (Table 6). Other problems mentioned by farmers that limited fish production included lack of market, storage and transport facilities, predators, parasites and poor water quality, but these were ranked as less important. The most prevalent parasite reported was leech (95% of the respondents).

Ownership of fish

The fish stocks comprised different species, but majority of the fish reared were O. niloticus L. Compared to the other two Counties, Kakamega tended to have more fish per farmer. This could be directly related to the large average land sizes. The three Counties differed significantly (P<0.05). The total mean percentage distributions for the three Counties were, 37.4, 27.7 and 34.9% for Kakamega, Kisii and Siaya, respectively (Table 7).

Most farmers ranked cattle first, followed by fish, goats/ sheep, poultry and bees, respectively (Table 8). Cattle ranked first because of their value to the family in terms of daily milk and cash income supply.

Species and breeding management

Species kept, their source and traits of economic importance

Nile tilapia, Oreochromis niloticus, were predominantly reared by most farmers (n=58; 56.8%) while 37.3% (n=38) of farmers owned mixed species (Clarias gariepinus, O. esculentus and O. variabilis) (Table 9). Some farmers (n=6; 5.9%) had no information on the specific species they owned. Most farmers purchased their replacement and foundation stocks. 

A range of traits as perceived by the farmers for the preferred species (O. niloticus) are presented in Table 10. Mothering ability, growth rate, size, survival, hatchability, feed conversion efficiency, adaptability and resistance to parasites were considered important (Table 10). However, only three traits were significant (P<0.05).

Mating ratio, average age at sexual maturity and average egg production

Controlled fish populations within the households that practiced O. niloticus polysex production were predominant across the three Counties (on average 76%), with the rest 24% unable to control the population. This was mostly done through the introduction of C. gariepinus as a predator when the O. niloticus had attained at least 4 months of age.

Natural mating was predominantly practiced by all farmers who reared O. niloticus. First mating in ponds was done when the fish attained maturity at about 4-5 months of age (200–250g body weight) for both males and females. A slightly wider range of 7-9 months was reported in C. gariepinus. An average mating ratio of one male to two females was used by most of the farmers (81%) while the rest 19% used one male to three females. Across the three Counties, on average, 250-1,000 eggs were produced per spawn for an average sized female, and the spawning trend was said to increase with age. Most farmers practiced polygyny breeding (male mated to several females) and vice-versa (polyandry).

Feeding

All farmers gave supplementary feed to their fish. A significant number of the respondents from the three Counties used maize grains, vegetables, by-products, e.g., omena (Rastrineobola argentea) remains and fish meal. Some farmers used sweet potato vines, brans, fruits, cakes and kitchen waste (Table 11). None of the respondents used mineral supplements across the three Counties.

The number of times the farmers fed their fish per day varied across the three Counties, with majority (71.6%) of them feeding twice in a day, 14.7% feeding once and the minority (13.7%) feeding thrice.

Health, pest and parasite management

Majority of farmers across the three Counties indicated few incidences of disease outbreaks (Table 12). A significant number of the respondents reported a strong problem of parasites (particularly Leeches). The Tillapiines were reported to be more susceptible to the parasite than the C. gariepinus. Most of the respondents controlled the parasite by dry drainage of the ponds after harvesting. Pests also seriously affected farmers; birds, especially, the Kingfisher and frogs had a major effect while theft of the fish was a minor issue.

 Marketing

Most of the farmers sold their harvested fish both at local and urban markets (Table 13). Only a few sold them directly to the local and urban markets immediately after harvesting at the farm-gate.

The sale price of the fish across the three Counties varied depending on the weights of the fish, from the lowest price for the fingerlings to average price for fish weighing over 100g (Table 14).

Discussion

The focus of the present study was to provide a better understanding of production and marketing systems and practices of smallholder fish farmers in Kenya. This is important in initiating any production and genetic improvement programmes (Ponzoni 1986). The key issues are discussed next in the sub-sections below.

Traits of importance

Growth, size and feed conversion efficiency were ranked as the most important traits in the choice of species kept. This makes it possible to select for these traits within the fish species that farmers kept and at the same time maintaining the superiority of their adaptability traits. Other traits considered were mothering ability, survival rate, hatchability, adaptability and resistance to parasites, which agrees with the findings of Nandlal and Pickering (2004). This is also in agreement with previous observations by Fryer and Iles (1972) that Tilapias are among the most important warm water fishes used for aquaculture production. Among the Tilapiines, the Nile tilapia (O. niloticus L.) and its hybrid are the most important cultured fish species (Charo-Karisa et al 2006). It is becoming an increasingly important food fish in many parts of the world. Although principally herbivorous in nature (Moriarty 1973) O. niloticus can feed on a wide variety of natural food organisms found in organically fertilized ponds (Yashouv and Chervinski 1961) as well as on artificial feeds. Majority of the culturing of O. niloticus is undertaken in the tropics in semi-intensive smallholder farms (Charo-Karisa et al 2006). From the findings in the current study, it would be possible to select for faster growth rate, good size and feed conversion efficiency.

Health management

Stocking a pond with healthy fingerlings in good physical condition should always be the top priority of a fish farmer. Aside from bacterial infections caused by handling stress, health per se was not an issue to most farmers because they were not losing a lot of fish to diseases, which agrees with reports from MoLFD (2006 and 2007). The major problem demonstrated in the current study was parasite (especially leeches) control, which mostly affected O. niloticus and rarely C. gariepinus. Most farmers appeared to use dry drainage of the pond and application of lime after harvest and traditional means for control (e.g., application of ash along the edges of ponds), but a significant proportion of the respondents left the situation uncontrolled, and a small proportion introduced C. gariepinus as a means of controlling the parasite. The number of extension visits to address problems pertaining to fish farming was found to be minimal. Some respondents discriminated against O. niloticus, citing their susceptibility to the parasite than the C. gariepinus. Pests also seriously affected farmers, and most farmers controlled them using traditional ways largely because they lacked other appropriate ways of control. This implied that farmers may in future prefer to rear C. gariepinus.

Ecological aspects

Climate and season influence supply and quality of the feed. Tilapia is farmed in varying environments based on density and the corresponding requisite additional inputs. The current survey revealed that all the respondents fed supplements throughout the year and, frequently fertilized their ponds for natural zoo- and phyto-plankton growth that fish naturally fed on. This is in agreement with the findings of Muendo (2006). In semi-intensive systems, fish are reared in outdoor stagnant ponds, but rely on fertilization to enhance natural feed production and/or on supplemental or complete feed to complement the natural feeds. The current study revealed that most farmers fed a variety of feeds, mainly maize grains. Use of genotypes that are adopted to efficiently utilize poor quality feeds may be a good option (Nandlal and Pickering 2004) but most farmers never mentioned it.

Marketing aspects

The current study revealed that most farmers sold their fish raw at local and nearest urban markets, with the prices varying with the weights of the fish. Fish were harvested and sold throughout the year. This presumably led to low prices because of lack of storage facilities for most farmers. Famers tended to sell with an aim to finish the day’s harvested fish. Most traders took the advantage of the situation and exploited the farmers by buying the fish at low prices. Farmers would, therefore, not likely adopt improved management practices while proceeds from sale of fish are low (MoLFD 2007). Current marketing information is largely informal and obtained by talking to buyers/ traders or sellers who have conducted transactions. The fact that most consumers were paying premium prices for fish species reared could influence the fish species adopted by farmers (Henryon et al 1998). To tackle the problem of marketing, cooling facilities are essential and farmers should have a collective approach on the matter.

Implications for a sustainable fish breeding programme

The results of the survey revealed a number of pertinent issues (i.e., constraints and opportunities) that, if well addressed, could help in the development of sustainable breeding programmes for fish under smallholder production and, therefore, increase the overall productivity of the fish. Among the major constraints, in descending order of importance, identified by the farmers were inadequate feed in terms of quantity and quality, finance, skills and lack of quality fingerlings. Due to high cost of feeds and limited protein sources, most farmers could not afford supplementary feeds. This agrees with other observations in developing fish industries (eg: Liti et al 2005). The problem of parasite control, especially leeches, was also an issue to be addressed. Feeds need to be made available and within the farmers' resources. If this is tackled, it would enhance sustainability of fish breeding programmes in future.

Generally, future improvement of fish should target traits like growth, size and feed conversion efficiency. The respondents strongly featured regular cash income, source of food and utilization of wetlands as reasons for rearing fish, with a few farming fish as a status symbol. This agrees with other observations (e.g., MoLFD 2003; Gitonga 2004). Other reasons like increasing human population, a factor that has led to reduced land sizes, together with availability of extension services reaching farmers, are likely to promote fish farming in the region, and these indicate that genetic improvement programmes for the fish could succeed if well planned.

A major constraint that most respondents raised was availability of fish with good genetic potential; fish that could grow fast and attain table size in a short period, and be able to utilize the available feeds well. This agrees with the findings of Mair (2007). The predominant use of own-farm breeding and uncontrolled mating within the farms increase the level of inbreeding. This indicates that, if farmers could be trained and encouraged to produce their own foundation and replacement stock at a reduced cost, then the success of future breeding programmes would be enhanced.

Natural mating was predominant and was practiced by all farmers who reared O. niloticus because it is simple and cheap to practice, but can also increase incidences of inbreeding. Controlled fish populations to avoid overstocking the ponds was common within the households that practiced O. niloticus polysex production. This was mostly done through the introduction of C. gariepinus, which reduced the population by eating them. This was done when the O. niloticus had attained at least 4 months of age, which was in agreement with the findings of Nandlal and Pickering (2004). Some males were kept for up to 3 years of age depending on the farmer’s objective, which may not be good production practice, especially if males are allowed to mate their own daughters. This can be disadvantageous in future fish breeding programmes if not well controlled and managed because it raises the level of inbreeding. Farmers, therefore, need to be taught and trained on virtues of a good breeding programme.

The results from the current study revealed that even with little knowledge on fish, farmers could still rear fish successfully, an indication of the importance of fish farming to the human population in the region. The respondents mostly practiced mixed crop-livestock farming with three or more farming activities besides fish farming, with a few engaging in off-farm work. The ranking of fish as second after cattle, coupled with low labour requirements and minimal effects of diseases and pests on the fish, indicated the increasing importance of fish farming as an economic activity in the study region.

Lack of alternative sources of income for majority of the respondents suggested strong reliance on agriculture and, therefore, farmers are expected to participate fully in fish farming if the constraints affecting them are curbed. This was evident from informal discussions with the respondents. Provision of storage and cooling facilities to farmers will enhance marketing and returns from fish farming and, consequently, improve the sustainability of fish farming in the region.

Conclusions

• The results from the current study indicated that fish farming was an activity that could generate regular cash income, create employment opportunities, ensure food and nutrition security, and enhance sustainable utilization of wetlands. This can only happen if farmers exploited the potential of existing fish species, which may be a solution to prevailing environmental, nutritional, production and management constraints, i.e., general application of good husbandry practices. Provision of information on market opportunities, both locally and on nearest urban centres, and constant training of seed stock producers (i.e., local farmers) are important for future planning and development of successful fish breeding programmes. Fish farming as a tool for alleviating poverty, and food and nutrition insecurity should, therefore, be undertaken with due regard to the farmers’ resources and management capacities to ensure success and sustainability of production. Development of initiatives to improve management practices is an overriding priority as it would lead to increased productivity in the short-term and foster the participation of farmers in the development of long-term fish improvement strategies.

Acknowledgement

We are grateful to the International Centre for Development and Decent Work (ICDD), Kassel University, Germany, for financial support, and Egerton University (Njoro, Kenya) and the Kenya Marine and Fisheries Research Institute for provision of facilities for the study.

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Received 8 September 2012; Accepted 21 February 2013; Published 1 March 2013

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