The building of hydroelectric dams has consequences on the ecological conditions of ecosystems, such as the regression or disappearance of certain species that have a benthic entomophagous diet or a proliferation of omnivorous and planktivorous species. The study of fish feeding can provide data not only on the presence of prey, but also on the abundance and availability of trophic potential. In view of the new hydroelectric development project on the Bandama River, this study proposes to examine the diets of Synodontis bastiani, S. schall and S. punctifer that are captured in the area. Stomachs were collected and contents examined from fish caught monthly between November 2019 and October 2020 using gill nets in the N'Dènou locality. A total of 417 fish belonging to S. bastiani, S. schall, S. punctifer were examined. The food spectrum of the studied species is wide and diversified. It is mainly composed of Macrophytes, Insects, Worms, Mollusks, Zooplankton, Crustaceans. These species are all omnivorous with a benthophagous tendency. No difference was observed in the diet according to the size.

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This study aims to characterize the spatio-temporal variation of the fish assemblages in relation to the environmental variables of Buyo Dam Lake. Sampling was performed from July 2017 to June 2018 using experimental fishing and commercial fishing. Spatio-temporal analysis indicated a significant variation (p <0.05) in pH, electrical conductivity, total dissolved solids, and water transparency. A total of 45 species from 27 genus and 15 families were collected in the samples sites. Two species (Chrysichthys johnelsis and Malapterurus barbatus) are reported for the first time in the lake of Buyo. Among the fishes sampled, of Cichlidae (35.04%) and Claroteidae (16.43%) were the most abundants. The abundant species are Oreochromis niloticus (15.55%) and Chrysichthys nigrodigitatus (15.15%). The analysis of the structure of fish assemblages (H' from 2.28 to 2.75, E from 0.68 to 0.84) revealed a fairly diverse lake environment. The canonical correspondence analysis revealed the significant influence of water pH, electrical conductivity, dissolved solids content, water transparency and nitrite in the distribution of fish species in the lake of Buyo. This work constitute a baseline study for future investigations and will contribute to the implementation of a sustainable management plan for fisheries resources in the continental water.

The Ivory Coast has economically and ecologically important rivers that contain various fish and shellfish resources. Thus, the present study aims to assess the length-weight relationships and the condition factor of fish stocks in selected sites on the Bandama River from July 2013 to June 2014. The growth pattern of each species was identified at the using a regression model calculated for the length-weight relationship. The condition factor (K) was analyzed for each species. There were six species of fish (Chrysichthys nigrodigitatus, Synodontis bastiani, Synodontis schall, Marcusenius senegalensis, Coptodon zillii and Labeo coubie). The length-weight relationship determined for the above six species showed a negative allometric growth pattern (b<3) indicating faster length increase relative to weight for five of them. They are Chrysichthys nigrodigitatus, Coptodon zillii, Synodontis bastiani, Synodontis schall and Marcusenius senegalensis, Only the species Labeo coubie presented a positive allometric growth (b>3) showing that this species put on weight faster than it grows. The habitat qualities of the majority of fish species were therefore in optimal environmental conditions. The results of the present study constitute a reference, which taken into account would be useful for the implementation of a plan for the sustainable management of fishery resources in Ivory Coast.

The management of fishery resources is a concern for managers of the fishing sector. The insufficiency of statistics in this sector is an obstacle to the sustainable management of fish. This study aimed at determining the fishing techniques, production and biological indices that characterize fishing in Taabo Lake. Data was collected from July 2019 to June 2020 in the Taabo-village station from surveys and analysis of fishermen's catches. Each identified specimen was weighed. The results of the study indicate seven fishing gears including conical fishing basket, castnets and gillnets with meshes smaller than the regulatory mesh. Purse seines and bamboo traps were specifically more selective (1 species). The seines have the annual catches (23,140 kg); CPUE (14.51 kg / exit); highest utilization (29%) and performance (46%) rates. An annual effort of 5501 fishing / trips for 50334.3 kg of fish caught characterized the fishing on Taabo Lake. This production is made up of 44 species belonging to 18 families. The Claroteidae family (47%) and the species Chrysichthys nigrodigitatus (46%) dominate the fish population of Taabo lake. This study provides our governments informations in their quest for the sustainable management of fishery resources.