Reproductive biology, length-weight relationship and condition factor of the African snake head, Parachanna obscura , from River Oshun, South-west Nigeria

Abstract

Aspects of the biology of the African snake head, Parachanna obscura, obtained from River Oshun, South-west Nigeria, from August 2006 to February 2007, were studied. Fish were captured with gill nets. The species attained a maximum total length of 36.4 cm and body weight of 389.36 g. The length/weight relationship indicated allometric growth for males and isometric growth for females. Gonado-somatic index ranged between 1.1 and 2.8% in the females. Values of condition factor were high for males. There were more females than males, and immature fish dominated the catch. Eggs ranged in size between 0.88 and 1.11 mm, while fecundity estimates ranged between 1711 and 4000 and were not related to length and body weight. P. obscura in this study did not show any distinct seasonal pattern of breeding. Key words: Parachanna obscura, River Oshun, Nigeria, reproductive biology.