Length-Weight Relationship and Condition Factor of Synodontis schall (Bloch & Schneider, 1801), from Roseires Reservoir, Sudan

Abstract

This study was carried out to investigate the length-weight relationship and condition factor of the Mochokid catfish S. schall, a commercially important fish species in the Roseires reservoir on the Blue Nile, Sudan. A total of 643 specimens were collected using the multi-filament gillnets of mesh sizes (4.0, 8.0, 10.0, and 12.0 cm) and twine (No. 2 and 12) during the period from November 2015 to October 2016; Samples were collected from four sites namely: Awal Bab, Elregiba, Kirma, and Wad El Mahi.; The length and weight of sampled fish were measured and recorded on the sampling sites and used to determine a length-weight relationship. The growth coefficient (b) ranged from 1.196 to 2.649, with moderate to high correlations (r) between 0.437 and 0.798. Values of (b) were less than 3 indicating a negative allometric growth pattern, whereas weight increased at a lower rate than length. The condition factor (K) ranged from 1.966 ± 0.696 to 3.856 ± 3.856, suggesting the fish were in good health condition throughout the sampling sites. The findings of this study provide valuable insights into the biological aspects of S. schall, which can form the basis of sustainable management and conservation policy for the fishery resource of this economically important fish species in the Roseires reservoir.