Abstract

Pérez González, Johannes C. Van der Wal, Hipólito Muñoz Nava and Salvador Morales Moreno

A study to assess the length-weight relationships and the condition factors of 3 abundant and commercial fish species namely Alestes baremoze, Brycinus nurseand Schilbe intermediusin the lower reaches of the White Volta River (Yapei) was conducted from October 2011 to March 2012. Using W = aLb, the length-weight relationships of the species were calculated. Condition factors of the species were obtained using the formula: W*100/Lb.A total of 284 A. baremozewere measured with total mid length size range of 10.5 to 44.5 cm. A total of 197 B. nursewere measured and ranged from 6.5 to 27.5 cm total mid-length whereas 175 of S. intermediuswere measured and had total mid length size range of 8.5 to 26.5 cm. The slope bof the length-weight relationships of the 3 species were within the acceptable range of 2.5 to 3.5 and can be used to approximate the weight for the 3 species in the lower reaches of the White Volta River. The condition factors variation of A. baremozeand B. nurseshowed a pronounced change in December 2011, when the surface water temperature was lowest. S. intermediushad no significant changes in the condition factors over the study period.