Summertime and the living is easy, fish are jumping and the cotton is high…
Recently my friend Sally was walking along her stretch of the Moordkuil River (which feeds in to the Little Brak River), when she came across a seething, shiny mass of African sharptooth cat fish in the shallows! Their scientific name, Clarias gariepinus, clearly makes them inhabitants of South Africa, and the rest of Africa, as the first one was found and identified in the Gariep (Orange) River. They don’t belong in the Western Cape at all however and are therefore regarded as invasive aliens in our river systems. They grow rapidly to their full size of 1 - 1.5 metres and 60 kgs and gobble up any smaller indigenous fish they can find. They are consequently bad news for our rivers.
One might wonder how these fish came to be in the Moordkuil. They are inadvertent escapees from a fish farm, or more likely in this case a fisherman introduced them into the river as they are good to catch and eat! For these reasons in the 1980s they were spread all over the world.