Etude de la diversité des poissons de la zone littorale du lac Tanganyika : cas des habitats des embouchures des rivières au nord de la ville de Bujumbura

Abstract

The ichthyologic diversity of Lake Tanganyika is under threat from anthropogenic pressure and pollution. A fish diversity study was carried out between December 2019 and April 2020 in the coastal zone of Lake Tanganyika near Bujumbura, at sites near the mouths of the Ntahangwa and Rusizi rivers. The objective was to contribute to the sustainable management of fishery resources. Adult fish were caught using gillnets and dip nets for fries. The Shannon and similarity index were also calculated. A total of 40 species were inventoried on two sites with a dominance of Cichlidae the family 77%. The other species occupied 23%. The fry was dominated by Limnothrissa miodon. The morphometric and weight parameters taken from each individual allowed us to carry out a structural analysis of the fish populations in order to determine the reproduction and growth areas or both for the species inventoried. The Shannon index of more than 1.5 indicates that the area is diversified. The similarity between two sites is low. The analysis of the population structure of the fish analysed revealed immature and mature individuals at the time of our sampling. The results indicate that the site is used for spawning and growth of the juveniles