The Swartkops River in Nelson Mandela Bay has turned black due to a harmful algae bloom. Now, conservationists fear this could spell disaster for a river and estuary that are already under threat from pollution. Scientists say while nothing can be done to remedy the situation at the moment, government should lower the amount of treated sewage which municipalities are allowed to discharge into rivers.
A harmful algae turned one of the main rivers in Nelson Mandela Bay red and then black, as conservationists blame high levels of sewage and warn that the public should not eat fish from the river.
"It is a disaster. We initially hoped that the Swartkops River would be spared," said Daniel Lemley, an expert in the ecology of estuaries. Lemley was part of the team that identified the harmful algae bloom on the river in March this year as Heterosigma akashiwo.
There is an ongoing campaign to have the Swartkops estuary, as part of the Zwartkops Conservancy, declared a protected wetland in terms of the Ramsar Convention. It is home to the mud prawn that provides food to 90% of 200 bird species in the estuary, and is also a source of food to...