Four hundred specimens of Chrysicthtys nigrodigitatus from Lagos Lagoon were examined for food and feeding habits. Duration and water samples were collected and analysed for four months. The total length of fish ranged from 11.0 cm to 39.0 cm while the standard length ranged from 8.0 cm to 31.9 cm, with a corresponding weight range from 17.0 g to 668.0 g. The length-frequency distribution followed the expected normal distribution with the small, medium, and large specimen being the lowest size range of (1.25%). The length-weight relationship showed the usual increase of weight with increasing length, and the species exhibit a positive allometric growth pattern. There was high correlation between the length and weight of the fish with regression coefficient (r) ranging between 0.87 and 0.94. The mean K-values were 1.86, 1.50 and 1.86 for males, females and combined sexes, respectively. The result of physico-chemical parameter showed that DO value ranged from 2.45 to 6.7 mg/L, BOD value ranged from 10.6 to 150.1 ml/L, COD value ranged from 65.1 to 256 mg/L, TDS value ranged from 156-545 mg/L, Nitrate value ranged from 1.02 to 4.11 mg/L, Phosphate value ranged from 0.51 to 2.11 mg/L, Copper value ranged from 0.1 to 1.71, Zinc value ranged from 0.01 to 0.71, Lead value ranged from 0.001 to 0.04, pH value ranged from 6.8 to 8.22, Conductivity value ranged from 8.72 to 71.4, Salinity value ranged from10.1 to 19.52. Physico-chemical parameter varies for different months and this is influence by rain fall, run off from the surrounding land and other factors in the Lagos lagoon. Physicochemical parameters however do not influence the food and feeding of C. nigrodigitatus in the Lagos lagoon.
Key words: Food, Feeding Habits, Chrysichthys Nigrodigitatus, Physico-Chemical Parameters, Lagos Lagoon, Nigeria
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