A Study on Food and Feeding Habit of Atya Gabonensis and Macrobrachium Macrobrachion and the Physicochemical Parameters of Lower River Benue at Wadata, Makurdi, Nigeria

Abstract

This study was done to investigate the food and feeding habits of Macrobrachium macrobrachion and Atya gabonensis from the Lower River Benue, Makurdi, as well as the influence of physicochemical parameters on their distribution. A total of 123 specimens of M. macrobrachion and 195 specimens of A. gabonensis were collected between August 2021 and January 2022 using basket traps and hand-picking techniques. Stomach contents were analyzed by numerical and frequency of occurrence methods, while water quality parameters (temperature, dissolved oxygen, pH, transparency, total dissolved solids, and electrical conductivity) were monitored monthly. The results of the analysis showed that M. macrobrachion had 14.5% empty stomachs, while A. gabonensis recorded 15.3%. Detritus formed the dominant food item for both species (30.6% in M. macrobrachion and 42.9% in A. gabonensis), followed by green algae, insect parts, and plant materials.  Seasonal variation in water quality was significant (p < 0.05) across most parameters. Dissolved oxygen peaked in November (6.70±0.10 mg/L), pH was highest in January (7.22±0.01), temperature was highest in August (37.30±0.10 °C), transparency peaked in December (189.50±0.50 cm), TDS in August (62.00±1.00 mg/L), and electrical conductivity in January (148.00±2.00 µS/cm). The findings of this work indicates that both species are primarily detritivores with tendencies toward omnivory. The findings also showed that the feeding ecology of M. macrobrachion and A. gabonensis is closely tied to detritus availability, with environmental factors such as water quality fluctuations or stability which influence food resources and feeding intensity. The results provide essential data for the management and conservation of freshwater prawn populations in the River Benue ecosystem.