38 SEPTEMBER 2012 Shifting rainfall and temperature regimes are bringing new challenges to the management of water bodies and fish farms in sub-Saharan Africa (Dixon et al. 2003). Culturing species that are resilient to drought and stressful water quality conditions may be a major part of future African aquaculture. Air-breathing fishes, such as the African lungfish Protopterus aethiopicus, can use atmospheric oxygen to meet all or part of metabolic demands (Mlewa et al. 2007). Airbreathing fish have a role in managed fisheries and low-management culture systems where dissolved oxygen concentration is not a limiting factor. Among air-breathing fishes, the African catfish Clarias gariepinus can tolerate low levels of dissolved oxygen but its flesh is held in lower esteem by consumers as compared to lungfish. The quality of Pangasius catfish flesh is high but it is not a native species in Africa. African lungfish is native to the natural waters of Uganda (Greenwood 1958, 1986, Birt et al. 2006) but populations are rapidly declining and the species is now endangered, mainly caused by overexploitation, environmental degradation and large-scale conversion of wetlands to agricultural land (Goudswaard et al. 2002, Balirwa et al. 2003). Therefore, it is essential to develop aquaculture to relieve pressure on natural stocks. This article explores the potential of African lungfish aquaculture to improve food security and livelihoods in Uganda; identifies indigenous production practices and approaches; consumer perspectives and markets; and an outlook for lungfish fisheries and aquaculture in Uganda and sub-Saharan Africa. Lungfish Biology and Ecology African lungfish are members of Class Sarcopterygii3, lobefinned fishes, obligate air breathers, with reduced gills in adults4. The species is widely distributed in freshwater ecosystems, including swamps, rivers and lakes of sub-Saharan Africa (Greenwood 1958, 1966, 1986). In nature, lungfish are periodically exposed to water with low dissolved oxygen and seasonal drought. In response, lungfish will aestivate for several months in mud cocoons, re-emerging when water levels rise. Lungfish are carnivorous, feeding on crustaceans, aquatic insect larvae and mollusks. Feeding on snails makes lungfish a suitable biocontrol agent for schistosomiasis (Daffalla et al. 1985). The African lungfish has a beak like that of a snapping turtle and dentition in the form of sharp occluding blades that make handling live fish hazardous. Lungfish reproduce by laying eggs inside a burrow made in shallow water during the rainy season when temperatures reach 24 C (Greenwood 1958, 1986, Mosille and Mainoya 1988, Mlewa and Green 2004). It is very difficult to visually distinguish males from females because genital structures are similar. There is also asymmetry in the position of the cloacal opening in both sexes (Mlewa and Green 2004). Males have broader pectoral fins and snouts than females (Greenwood 1958). The Lungfish Fishery Lungfish are captured using gillnets, hooks on long lines and basket traps. The basket traps (ekolo) are mainly used to catch lungfish in seasonal wetlands. In the dry season, January to March, aestivating lungfish can be dug up easily from holes when residents cultivate or hunt in wetlands because the fish are relatively inactive. Women play a major role in lungfish hunting, post-harvest processing and marketing. In Pallisa and Busia districts, lungfish, nakibalo or mamba (P. aethiopicus) were harvested using hooks (no. 5-12), gill nets (10.2 to 11.4 cm mesh), baits (pieces of meat, rats and frogs), basket traps and spears. Most fish caught with gill nets and hooks are mature Prospects and Potential for Aquaculture of African Lungfish in Uganda John Walakira 1, Gertrude Atukunda,1 Joseph Molnar 2 and Karen Veverica 2 FIGURE 1. Map of Uganda indicating districts visited for farmer and consumer surveys and districts suitable for pond aquaculture.
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