Threats
Water is in great demand in this dry ecoregion, with both urban and agricultural uses competing with the needs of the unique aquatic fauna, also causing pollution.
The construction of dams and interbasin water transfers alter the natural flow regime and block species movements. Introduced species, particularly North American gamefishes such as
Largemouth bass (
Micropterus salmoides) and Smallmouth bass (
M. dolomieu) have heavily impacted indigenous species.
Of the 19 indigenous fish in the fynbos system, 16 are endemic - meaning they occur naturally nowhere else on Earth - and 15 are already highly threatened because of loss of habitat; the building of dams and weirs; channel modification through bulldozing; the presence of invasive alien vegetation like
eichornia (water hyacinth), parrot's feather and black wattles; and the introduction of alien fish like bass, carp and trout.