Population trend
Trend
Recent fish surveys by the provincial conservation agency CapeNature indicate that the following rivers have healthy subpopulations (good recruitment and large numbers of fish); Biedouw, Driehoeks, Gif, Jan Dissels, Matjies, Olifants (gorge area), Oorlogskloof-Kobee and Ratels. New subpopulations have been recorded in the upper Boschkloof, Dwars, Eselbank and Langkloof rivers, but these are small populations with very restricted distributions because of bass invasion. There are thriving subpopulations in two off-stream dams: Beaverlac Dam in the Ratels Catchment and the main dam at Bushmanskloof Nature Reserve, on the Boontjies River in the Brandewyn Catchment. The latter dam population is extra-limital in that the dam is above a large waterfall which use to be a barrier to fish (Impson and Tharme 1998). There are thus 11 riverine subpopulations and two dam subpopulations. Where alien fish, especially bass (Micropterus spp.) predominate in the ODRS, the adult fish of this species is present in very low numbers (for example Doring River), or is locally extirpated (for example middle and lower reaches of Olifants River). Surveys of the Doring River indicate that numbers are declining (Paxton 2008).