South Africa uses insects to fight invasive species

Water hyacinth, an aquatic weed from South America, is widely regarded as one of the world's most problematic plants. 

It has spread across the globe and invaded local waterways, making them difficult to access. It also presents an environmental challenge by outcompeting native species and creating a dense mat of leaves across the water's surface that prevents sunlight from reaching plants and animals below.

Since arriving in the early 1900s in South Africa, water hyacinth has spread throughout the country. Attempts to control its growth using chemical herbicides or removing it by hand or machinery have had little impact. 

In 2019, the Center for Biological Control(CBC), part of Rhodes University in the country's Eastern Cape Province, introduced a new tool in the fight to control the invasive species: a native insect called the planthopper. 

Since 2019, the CBC has bred over 1 million planthoppers at a special facility and put the insect army into action on the Hartbeespoort Dam, where hyacinth covers more than 40% of the surface area of the water. 

A film by Jason Boswell