The ichthyofauna diversity of the Jebba Hydroelectric Power (HEP) Dam, Jebba, North-central Nigeria was studied. Fishes were sampled for 24 months using gill net, hook and line, and cast net. Individuals were identified using morphological and molecular (mitochondrial Cytochrome c Oxidase subunit I) data. A total of 9605 freshwater fishes were recorded during the sampling period. The use of an integrative taxonomic approach enabled the identification of 83 species belonging to 42 genera. Additionally, the study recorded three unidentified species – Ctenopoma sp, Malapterurus sp., and Protopterus sp. Analyses showed that individuals belonging to families Cichlidae and Mochokidae dominated the dam. The diversity analyses revealed relatively high fish diversity during the rainy season at the downstream section of Jebba HEP dam compared to the upstream section. The study, therefore, showed the presence of a diverse fish community comprising high species richness and diversity across the Jebba HEP dam. Finally, we recommend proper biodiversity monitoring and assessment of freshwater fish diversity across Nigeria. In addition, the use of an integrated taxonomic approach is recommended for appropriate species’ identification and studies of freshwater fishes from Nigeria.

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As Fish farming (Aquaculture) is the most efficient husbandry method for animal protein production, an assessment of catfish farming in Osogbo and Osun state was undertaken. An assessment was carried out among 53 catfish farmers between January and April, 2013 using questionnaires conducted via face-to-face interviews. The results revealed that there are large numbers of fish farms in and around the Osogbo area. Twenty (37.74%) of the fish farms are commercial farms while thirty-three (62.36%) are homestead. Results also showed that there were more males are than females working in these fish farms. The two prominent religious faiths, Islam and Christianity are both represented by the employees, indicating that it there are no religious restrictions. The semi-intensive system of fish farming with concrete and earthen ponds was being adopted by the farmers and there has been steady development over the last five years. Insufficient funds for expansion, unpredictable weather, fishseed mortality, irregular price of feed ingredients and pricing of products, among other factors, are the major challenges faced. Useful suggestions and recommendations are offered to address these challenges and sustain business growth.

Fish protein is regarded as quality protein being rich in essential amino acids with a high digestibility value. The biochemical composition of the fish differs with the change in habitat as well as season. Samples of freshwater catfish (Clarias gariepinus) from Upper Jebba Basin, Nigeria were analyzed during the dry and wet seasons to study the variation in proximate composition of nutrients and mineral content using standard procedures in dry weight basis. The results revealed the presence of the moisture content with an average mean of 4.26 ± 1.04% in dry season while wet season recorded 5.63 ± 1.27%. The ash content in dry and wet season is 6.10 ± 0.85% and 4.66 ± 0.46% respectively while the crude fibre were generally low with significantly variation (P<0.05) between 0.84 ± 0.12% in dry months and 0.57 ± 0.25% in wet months. The average mean values of crude protein were slightly higher at 64.47 ± 0.58% in wet months than 63.10 ± 2.10% in dry months. Variation in crude fat content for both season were within a narrow range with an average mean of 4.03 ± 0.16% and 4.09 ± 0.03% for dry and wet season respectively. Average Nitrogen Free Extract (Carbohydrate) of 20.76 ± 1.43% in dry season was comparatively higher than 19.86 ± 1.55% in wet months. The mineral composition of the fish in both seasons varied significantly (P<0.05) in Ca, K, Cu and Zn% mean concentration.

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