Nile tilapia (Oreochromis niloticus) has become invasive in many African water bodies (rivers, lakes, wetlands). The invasive nature of Oreochromis niloticus in Lake Victoria, East Africa and in the Congo Basin is well known. It competes with other cichlids such as Oreochromis esculentus and O. variabilis (Twongo, 1995). This fish species is now very valuable in Lake Victoria. In Kinshasa, the monk fish farm Prieuré Notre-Dame d’Assomption introduced Oreochromis niloticus in the 1980s; it is now widely spread and commonly sold (becoming therefore an important source of income and nutrients).This is also true with Heterotis niloticus, recently escaped from the upper Ubangi river (Central African Republic) and which has invaded the Congo river and tributaries. In the beginning fishers complained, but now are benefiting from this fish species and satisfying consumer needs in Kinshasa (Musibono, 1992; Shumway et al., 2002).

Mangroves, which are important spawning areas in coastal zones, are being degraded by various factors such as pollution from oil companies, deforestation for charcoal production and fishing with chemicals.

2.4.3. Quality of produce and productivity
As stated above, most production systems are artisanal and traditional. Aquaculture production systems are increasing and may become the main fish supply (ICLARM-GTZ, 1991; Jamu and Brummett, 2004).

Timing of extraction. Fishing (capture) occurs more during the dry season. During the rainy reason, fish species move into the spawning areas in marshes, grasses and other plant systems, and fishing is not allowed. Unfortunately, where traditional fishing is dominant, fishers are increasingly exploiting spawning areas with chemicals such as pesticides and toxic plant extracts. These practices are poverty-induced and anti-conservationist, especially in the D.R. Congo (Shumway et al., 2002). Indeed, the use of poisons in spawning zones destroys the biodiversity, especially eggs, fingerlings and juveniles and the renewal of the fish stock is thus compromised.

Processing, value-addition and utilization. The fish industry is very poor in the SSA region, except in South Africa, Uganda, Nigeria, Mauritania, Mauritius, Namibia and partly Ghana where fish are processed for export. In South Africa and Madagascar, fish are even canned. In most cases, fish are well processed for export. Local markets do not enforce minimum standards.

The potential for the fish industry is high, but as yet undeveloped. An increase in industry will result in an increase in the market value of fish. Promoting the fish processing industry in SSA will help maintain fish biodiversity and help reduce poverty.

Fisheries and aquaculture in SSA offer a huge potential for sustainable development. Unfortunately, fish biodiversity, systematics, ecology and conservation strategies are not well-known. Despite the fact that most SSA countries have signed the Convention on the Biological Diversity, AKST inputs remain negligible. Due to high biodiversity indices, the Congo Basin needs particular attention to fish biodiversity management. Ongoing work by a US NGO, Innovative Resources Management, the American Museum for Natural History and their local partner environmen-

tal Resources Management and Global Security could be supported.

2.5 Bioenergy
Biomass is a renewable energy resource derived from the carbonaceous waste of various human and natural activities. It is derived from numerous sources, including the by-products from the timber industry, agricultural crops, raw material from the forest, household waste and wood. Biomass is the most important source of energy in Africa today, meeting more than 50% of its total primary energy consumption of 20.7 EJ (IEA, 2002). However, while much of the public discussion in the world today is focused on modern, efficient and potentially environmentally sustainable forms of bioenergy, Africa relies to a great extent on traditional sources of bioenergy that are associated with considerable social, environmental and economic costs.

African countries are the most intense users of biomass in the world and there is a strong correlation between the use of biomass as a primary energy source and poverty (Table 2-2). In the poorest countries the share of biomass in residential energy consumption can reach up to 90%. Similarly, within countries the use of biomass is heavily skewed towards the lowest income groups. In rural areas 92% of the population does not have access to electricity and thus has to rely almost entirely on biomass, LPG and kerosene to meet its energy needs (IEA, 2002).

Predominantly, this biomass energy consists of unrefined traditional fuels such as firewood and crop and animal residues used for essential survival needs such as cooking, heating, lighting, fish-smoking and crop drying. For example, in Kenya, Tanzania, Mozambique and Zambia, nearly all rural households use wood for cooking and over 90% of urban households use charcoal. These forms of traditional bioenergy are associated with considerable social, environmental and economic costs and are believed to be a consequence of poverty and at the same time an inhibitor to social and economic development (UNDP, 2000; IEA, 2002; Karekezi et al., 2004).

The energy efficiency of traditional biomass fuels is very low, especially when used in traditional cooking stoves, leading to a variety of problematic effects. First, the amount of fuel necessary to generate one unit of energy service (e.g., kilogram of wood per lumen of light) is very high, putting considerable strain on those environmental resources that supply the biomass. This poses a threat to natural vegetation but is also problematic for agricultural and animal residues, which are not available as fertilizer or fodder when they are used as energy sources. Inefficient combustion of biomass in traditional cooking stoves is also responsible for high levels of indoor air pollution leading to poor health. Each year 2.5 million premature deaths are caused by the fumes generated by traditional biomass stoves (WHO, 2002). Moreover, traditional sources of bioenergy are often associated with time-consuming and burdensome collection. In many cases, women and children are forced to devote several hours each day to the collection of fuel for cooking, significantly reducing the time they can devote to other productive activities, such as farming and education (UNDP, 2000; IEA, 2002; Karekezi et al., 2004; World Bank, 2004).

Modern energy services can alleviate many of these