Biology and prospect for aquaculture of African bonytongue, Heterotis niloticus (Cuvier, 1829): A review

This paper first reviews the available data on the biology of Heterotis niloticus, and then the prospect for sustainable aquaculture of this species. Previous researches principally investigated its reproduction and growth in natural environment. Thus, Heterotis has an unpaired gonad located on left side; the spermatogenesis and oogenesis of this species are similar to those of most teleosts. Heterotis has an elaborated reproductive behaviour (coupling, nest construction and parental guarding). The species is classified within the opportunistic omnivorous fish category and consume a variety of food resources, ranging from aquatic invertebrates to small seeds, including small benthic organisms, fishes, shrimps, plant remains and terrestrial insects. In captivity, remarkable growth performances have been reported, individual mean body mass reaching up to 3 to 4 kg in 12 months. However, its use for profitable fish-farming in Africa relies on the knowledge of ecological, behavioural and nutritional factors which condition its reproduction, the resolution of massive mortality during early ontogeny, the estimate of its nutritional needs at various ontogenetic stages and the identification of an efficient breeding. The prospect for Heterotis contribution to the rise of African aquaculture depends on the solutions which will be found to the mentioned crucial problems.