Authors : M.E. Allison , I.F. Vincent-Akpu and A.D.I. George
Abstract: Gillnet selectivity and abundance of the Parailia pellucida fishery in the freshwater reaches of the lower Nun River was investigated using gillnets of 8, 12 and 15 mm classified as Small (SMS), Medium (MMS) and Large (LMS) mesh sizes, respectively. The nets exhibited selectivity with SMS catches ranging from 4.0-5.1 cm and mean of 4.70 cm Standard Length (SL), MMS between 5.0 and 6.5 cm and a mean of 5.6 cm SL, while that of the LMS gill net ranged from 6.0-10.5 cm with a mean of 7.3 cm SL. Apart from size selectivity, there was a significant difference in abundance and biomass of P. pellucida with mesh size of gill net used (p<0.05, t = 1.969, df = 2, N = 144) such that the LMS consisted of the highest abundance of 6,762 (74.4%) and biomass of 29.485 g (84.0%), the MMS 2.381 specimen (25.2%) and biomass of 5.238 g (14.8%), while the SMS constituted the least abundance of 269 (2.8%) and biomass of 409 g (1.9%). The mean monthly abundance and biomass were: SMS -11.21 (17.09 g), MMS -85.58 (217.21 g) and LMS -281.75 (1.230 g).
M.E. Allison , I.F. Vincent-Akpu and A.D.I. George , 2009. Gillnet Selectivity and Abundance in the Parailia pellucida (Boulenger, 1901) (Schilbeidae) Fishery of the Freshwater Reaches of the Lower Nun River, Niger Delta, Nigeria. Journal of Fisheries International, 4: 5-7.