This study assessed how environmental parameters such as salinity, dissolved oxygen (DO) and turbidity influenced occurrence of the bagrid catfish Chrysichthys nigrodigitatus population in the Pra Estuary, their food habits, and how food preferences vary amongst the sizes. Fish were sampled from January to April 2017 using cast net. Physicochemical parameters were measured in situ using multi-parametric water quality checker. Length and weight of fish were determined, and with the aid of dissecting microscope, stomach contents were examined using the frequency of occurrence and points methods. Salinity showed a general downward trend with the highest of 30 in January and lowest of 1 in April, DO fluctuated between 4 mg/L and 5 mg/L, while turbidity increased progressively from 8 NTU in January to 207 NTU in April. The number of fish caught decreased as turbidity increased and salinity decreased. A total of 282 specimens measuring 8.0 cm to 42.5 cm (TL) were sampled of which fish smaller than 17 cm were dominant. The catfish fed on detritus, insects, polychaetes, oligochaetes, bivalves, amphipods, shrimps, crabs and fish, with detrital matter being the most consumed food item. Recommendations are made for management considerations to address illegal mining activities which silt the estuary as well as regulate fishing practices such as the use of small meshed-nets that capture juveniles and bottom drag nets that deplete the food of the catfish.
Key words: Pra Estuary, Water quality, Bagrid catfish, Food habits, Fisheries Management
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