EU research results


English EN
Integrating BOMOSA cage fish farming systems in reservoirs, ponds and temporary water bodies in Eastern Africa

Integrating BOMOSA cage fish farming systems in reservoirs, ponds and temporary water bodies in Eastern Africa

Final Report Summary - BOMOSA (Integrating BOMOSA cage fish farming systems in reservoirs, ponds and temporary water bodies in Eastern Africa)

The BOMOSA project examined the economic viability, social acceptance and necessary institutional environment of an existing, technically feasible, relatively simple fish farming technology which aimed to integrate agriculture with aquaculture in East Africa. In that way additional income and high protein food would be available to local populations.

BOMOSA scientific and technical objectives were the following:
1. to define targets in terms of economic viability and social acceptability through the application of a participatory approach;
2. to develop en evaluation method for water bodies using remote sensing, so as to identify potential BOMOSA plots sites;
3. to optimise the technology through field application;
4. to evaluate agricultural by-products and processing technologies as a resource for the sustainable production of low in proteins fish feed;
5. to determine requirements and provide recommendations for an adequate legal and regulatory framework;
6. to produce dissemination material for the local communities, relevant authorities, policy makers and international scientific community;
7. to propose a socioeconomic model for sustainable introduction and widespread uptake of the BOMOSA scheme in Eastern Africa.

The proposed technology consisted of netlike fish cages which could be folded, easily transported and handled by two persons without mechanical aid. The BOMOSA scheme was a network of small-scale operations with rural communities setting up and exploiting the plots. Existing fish farms were employed to supply fingerlings for rearing within suitable water bodies. Farmers were trained to rear the fish in cages, harvest them for consumption and selling and process them for long-term storage. Thus, the fish became both a dietary supplement and a source of additional income.

A communication plan was established to ensure that the various stakeholder groups shared the same adequate and consistent principles. Committees located in the field sites served as a dialogue platform integrating local communities, scientists and governmental officials. A wide range of dissemination technologies such as a specific website, meetings, workshops and participations in conferences was employed and relevant material was produced. The BOMOSA technology was incorporated in the academic curriculum of East African universities. Moreover, a conference was organised during the project to facilitate discussions, increase communication and present the project approach. The key objective of achieving holistic involvement of the local communities was therefore successfully realised.

Criteria for selection of BOMOSA plots sites were developed, along with feeder technology and fingerling transportation protocols. The sites selection criteria included environmental, infrastructure, and socioeconomic components and were described within a checklist based on the already acquired experience of the system application in Kenya. Water quality was a major concern in order to ensure adequate fish cultivation conditions.

The plots were constructed in three different countries - Kenya, Ethiopia and Uganda - and four different climatic zones, namely in humid areas, river and lake floodplains, highlands and semi-arid regions. Three plot site types were implemented, with floating piers to accommodate water fluctuations within the water bodies. The cages were designed to float without collapsing; hence, maximum effective volume was constantly achieved. Moreover, affordable, easily maintained clockwork feeders were designed and applied, while the fingerling transportation protocols were successfully implemented in all cases.

Analysis of the existing plots was necessary in order to design the environmental monitoring program of the new sites. Remote sensing (RS) techniques were applied to evaluate potential sites for the technology expansion. The developed method met criteria of low-cost, simplicity, universality, high accuracy and reliability. Land cover was an essential subject of all RS data based analyses. It was assessed using the gradual supervised multispectral classification approach. The proposed methodology was verified using maps integrated with geographical information systems (GIS) with satisfactory results. Training courses were hence provided to local stakeholders and a manual for the method application was issued as part of the technical implementation plan (TIP).

Veterinary and public health aspects of the cage culture system were evaluated so as to ensure the safety of the proposal. Water quality parameters which ought to be monitored since they influenced animals' health were, therefore, determined along with other risk factors. Cooking of the fish proved to be sufficient to ensure that parasitic organisms could not enter the human food cycle.

Legal and policy documents concerning aquaculture institutional environment were collected in all the participating countries to allow for the assessment of the existing regulatory framework on aquaculture. International policy documents were also taken into account. Appropriate recommendations were formulated based on this assessment. They concerned fisheries and aquaculture, environment and water resources, animal diseases, food safety and public health.

Several agricultural by-products were analysed in terms of their nutrient contents, developed for fish feeds and tested for their acceptance in many independent field studies. Criteria for diet potential ingredients' evaluation were the local availability and abundance, the levels of crude protein, crude fibre and total ash content, the cost per nutrient, the necessity for least competition with other users and the absence of anti-nutritional factors. Diets targeting different regions and plots were subsequently formulated. Their acceptance by fish was clearly different for alternative feedstuffs depending on texture, silage and quality. The diets which performed best in the analyses were also tested in growth performance experiments.

In addition, simple feed processing and dispensing devices such as inexpensive mixers, hand mills and pelletisers were fabricated or modified for fish feed production. Feed package and storing options were also examined, since they could increase preservation period and reduce seasonal variations of feedstock availability.

Studies of various parameters were performed throughout the BOMOSA project in order to increase its efficiency. The optimal fish growth performance as a function of feeding rate and frequency was evaluated. The economic performance was also monitored on the basis of the output of growth studies, since profitability was essential for the system application by individual farmers. Different strategies were analysed and tested to reduce the high fingerling mortalities and increase the overall productivity. Finally, a literature review of post-harvest methods was conducted along with smoking trials for the conservation of overproduction. The outcomes of the undertaken research contributed to the development of the BOMOSA manual.

Finally, the factors that affected social acceptability of BOMOSA were determined and analysed. They included ethical and gender concerns, apprehension of the society, perceived benefits and costs, management issues and environmental implications. A strategy for addressing these factors in order to maximise sustainable propagation of the technology was afterwards designed, resulting to the formulation of a TIP, which continued after the project completion.

Project information

Grant agreement ID: 32103

  • Start date

    1 October 2006

  • End date

    30 September 2009

Funded under:


  • Overall budget:

    € 1 659 473

  • EU contribution

    € 1 499 998

Coordinated by:


This project is featured in...