Beware! The locusts are swarming this summer

South Africa looks to be heading for another large-scale brown locust outbreak this season, according to Dr Gerhard Vedoorn of CropLife South Africa and Dr Roger Price of the Agricultural Research Council. They spoke to Glenneis Kriel about the most effective means of combating these swarms.

- Glenneis Kriel

FAST FACTS

Government is ultimately responsible for managing locust outbreaks.

Outbreaks need to be reported as soon as possible.

New technologies, such as drones and a GPS-linked app, can improve control strategies.

Overall conditions favour the development of giant populations of brown locust (Locustana pardalina) this summer.Hundreds of adult swarms were reported in the Karoo during the autumn months of 2020 and 2021, and laid their eggs over a wide area. These lay dormant during winter, but are now hatching in large numbers. In addition, normal to above-normal summer rainfall has been forecast for South Africa, and this will increase the chances of survival for the hatching hoppers. According to Dr Gerhard Verdoorn, operations and stewardship manager at CropLife South Africa, widespread small outbreaks have already been reported in the Springbok and Concordia areas of the Northern Cape, and the GraaffReinett, Cradock and Aberdeen districts of the Eastern Cape. “These reports are worrying, as they were received much earlier than usual,” he says.

THE PROBLEM

Dr Roger Price, research team manager at the Agricultural Research Council’s Plant Health and Protection Unit, explains that L. pardalina is endemic to the Nama-Karoo region, which covers most of the Northern Cape and parts of the Eastern and Western Cape and southern Namibia.

It has an average lifespan of 78 days, with hatchlings developing through five stages, spanning about 56 days, before reaching sexual maturity. The female can produce up to 380 eggs in her lifetime.