According to monitoring by the Centre for Biological Control (CBC) of the Rhodes University, the water hyacinth cover on Hartbeespoort Dam was down to 13.63% last weekend.
The biocontrol agents have effectively controlled the water hyacinth.
“There have been a lot of questions/statements around what happens to the dying water hyacinth – where does it go? In contrast to a herbicide application where the mat of water hyacinth dies rapidly and sinks, releasing nutrients that result in algal blooms, the action of biocontrol agents is much slower. So the death of the plants takes a long time and is distributed over the dam as the plants move with wind and wave action. There isn’t a sudden release of nutrients, so the associated algal blooms don’t occur. We want to thank everyone for their support,” the CBC said.