Latest Freshwater Fish Conservation Status in Southern Africa RevealedGeneral

In the field searching for barbs are (from left) Mr Lungelo Madiya, Dr Gordon O’Brien and Mr Mahomed Desai.In the field searching for barbs are (from left) Mr Lungelo Madiya, Dr Gordon O’Brien and Mr Mahomed Desai.

The conservation status of existing and new fish species in KwaZulu-Natal was updated during an International Union for Conservation of Nature and Natural Resources (IUCN) red list assessment workshop for freshwater fish in southern Africa.

The workshop, hosted by the South African National Biodiversity Institute (SANBI) at the South African Institute of Aquatic Biodiversity (SAIAB) in Grahamstown, was attended by the leader of the Aquatic Ecosystem Research Programme at UKZN, Dr Gordon O’Brien.

Numerous regional scientists and conservationists representing hundreds of years of experience were present.

O’Brien, who accompanied Ezemvelo KZN Wildlife Freshwater Ecologist Mr Skhumbuzo Kubheka, noted the attendance of leading researcher, Professor Paul Skelton

Key outcomes include the revision of a range of new fish for KwaZulu-Natal and the listing of many species as threatened due to multiple stressors.

‘KwaZulu-Natal had fewer than three freshwater fish listed as threatened in the early 2000s but this may now have tripled with some species possibly endangered or critically endangered,’ said O’Brien.

‘KwaZulu-Natal has close to 100 species of freshwater fish, many endemic and many new species of barbs (Enteromius spp.) have recently been discovered and described.’

UKZN has worked closely with Ezemvelo over the past three years to look for these barbs in KwaZulu-Natal rivers, especially in threatened systems. They have also had support from Umgeni Water, the Department of Water and Sanitation and the National Research Foundation.

‘We’ve observed a concerning decline in the average diversity and abundance of many populations of fish in the province largely associated with changes in distribution of alien fish, land use practices and pollution, and most importantly the drought, which has decreased availability of surface water in numerous systems. Surviving fish have also been removed through pollution, habitat change and harvesting by local communities for subsistence and commercial trade. Such extreme conditions have never been observed, even in severe droughts in the 1990s.  There is no doubt the threats to the wellbeing of rivers are considerably higher today.’

O’Brien referred to several important outcomes such as reminders about the extinction of local species and the listing of species as threatened for the first time. He also noted the discovery and listing of new species, the increase in migration barriers throughout the province that reduce distribution (especially of eels), and the need to revisit the status of several species in coming years.

He emphasised that, while KZN-dwellers need fresh water for homes, industries, recreation and waste treatment, it was vital that everyone played a role in looking after that water and its inhabitants in return, notably through increasing knowledge and exploration of water systems.

Christine Cuénod