Nutritional Assessment of Selected Fish Species in Major Aquatic Bodies in Bayelsa State, Nigeria

Background and Objective: Fish from the aquatic environments of Bayelsa State and the Niger Delta region at large offer good nutrition; however, they face varying nutritional profiles due to the discrepancies in habitat. This comparative study investigated the nutritional profiles of the tissues of three economically important fish species, such as Clarias gariepinus (African catfish), Polydactylus quadrifilis (Giant African Threadfin), and Oreochromis niloticus (Nile Tilapia) in freshwater, saltwater, and brackish water, respectively. Materials and Methods: The study utilized twenty-one fish samples (seven per species) that were systematically collected from Taylor Creek (freshwater), Brass River/Atlantic Ocean (saltwater), and Nembe Creek (brackish). Association of Official Analytical Chemists (AOAC) methods were utilized for proximate analysis, whereas Atomic Absorption Spectrophotometry (AAS) was used for minerals in fish and water samples following methods described by the United States Environmental Protection Agency (USEPA). Data were analyzed using SPSS 27 with results as Mean±SD, and significance tested by One-way ANOVA and Tukey’s HSD at p<0.05. Results: The Polydactylus quadrifilis exhibited the highest protein content (28.80±0.14%) and the highest ash content (10.64±0.14%). Also, Oreochromis niloticus exhibited the highest moisture content (51.27±0.55), and Polydactylus quadrifilishad the highest fat content (19.45±0.24). Trace metal analysis showed that Oreochromis niloticus had elevated essential minerals, including calcium (13.164±0.7177 mg/kg), magnesium (6.907±0.7425 mg/kg), and sodium (7.748±0.7425 mg/kg), reflecting environmental influences. Conclusion: Results from this study showed excellent nutritional profiles across all species. Also, correlation analysis revealed very strong positive relationships between fish tissue and water concentrations for calcium, magnesium, and sodium. The comparative nutritional assessment across different aquatic environments is of great importance as it provides much-needed baseline data for food security and aquaculture management in Bayelsa State and the Niger Delta Region.