Government unleashes tiny insects to combat full-blown public crisis: 'The solution is laws addressing this source'
The South African government has a new weapon in its fight against invasive water plants: a tiny aquatic weevil from Florida, Devdiscourse reported.
The salvinia weevil is named for its favorite food. It eats massive quantities of common salvinia, a plant that is creeping across South Africa.
This water weed is an invasive species — a species that has traveled beyond its native environment to a new location where it is multiplying at a destructive pace. Left alone, it will take over, crowding out and killing off a wide range of other species and destroying the natural balance that has existed in that area for millennia.
In the case of salvinia, it was first sighted at Hartbeespoort Dam in 2011. Since then, it has spread as far as the Limpopo River, to the edge of Botswana. It clogs the water, interfering with the livelihoods of everyone who relies on the river as well as the diversity of water plants and the quality of the water.
The weevils are expected to multiply just as fast to address the problem. Crucially, they only eat salvinia.
"This biological control programme will be closely monitored to assess the weevil's progress and effectiveness in reducing common salvinia. Importantly, these weevils exclusively target the salvinia minima plant and do not pose risks to other aquatic vegetation, crops, or ornamental plants," said professor Julie Coetzee, deputy director of the Rhodes University Centre for Biological Control and principal scientist at the National Research Foundation's South African Institute for Aquatic Biodiversity, per Devdiscourse.
Water and Sanitation Deputy Minister Sello Seitlholo emphasized that a major cause of salvinia's spread, and one that must be addressed, is the excess nutrients in incorrectly processed wastewater.
"What is also important is for us to have serious discussions with municipalities in the upper catchment areas. The inadequate treatment of wastewater leads to high nutrient levels in the water, which in turn fuels the spread of invasive aquatic plants, degrading the ecosystem, affecting recreational activities, and hampering the local economy," Seitlholo said, per Devdiscourse.
The solution is a law to address this source of pollution — which will lead to cleaner, healthier water for all.
Should we be actively working to kill invasive species?
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