An assessment of the reproductive biology of the Marico barb Barbus motebensis from the upper Groot Marico catchment, South Africa

Abstract

Barbus motebensis is endemic to the Groot Marico River catchment in the North West province, South Africa, and is considered of particular conservation importance due to being Red-Listed as Vulnerable. Due to its vulnerable conservation status, the aim of this study was to provide information on its condition factor, breeding season, gonadosomatic index, fecundity range and length at maturity from specimens collected by means of electrofishing and seine-netting between November 2012 and May 2014 from the Draaifonteinspruit and Kaaloog se Loop. Length at maturity was estimated as 37.5 mm TL for males and 44.5 mm TL for females. Microscopic gonad staging and gonadosomatic index demonstrated that B. motebensis has an extended breeding season from spring to summer. Relative (578 eggs g⁻¹) and absolute (3 728 eggs) fecundity were relatively high for small barbs.

Keywords: condition factor, fecundity, gonadosomatic index, histology, length at maturity, spawning season