New fruit fly species detected in South Africa

Spotted wing drosophila has been confirmed in South Africa, posing a threat to most fruit production areas. However, efforts are underway to contain and manage the spread, writes Glenneis Kriel.

- Glenneis Kriel

The Department of Agriculture, Land Reform and Rural Development (DALRRD) recently officially declared the presence of spotted wing drosophila (Drosophila suzukii) in South Africa.

A single male fly was first identified from a trap at Misgund in the Langkloof, Eastern Cape, in late 2023, after which grower organisation Berries ZA, in collaboration with Hortgro, deployed traps in most berry-growing regions in the country to monitor the situation.

Since then, spotted wing drosophila (SWD) had been caught in Tzaneen in Limpopo; Curry’s Post in the KwaZulu-Natal Midlands; various locations in the Langkloof, which falls in the Eastern and Western Cape; and Barrydale, George, Montagu, Napier, Worcester, Wolseley, Riviersonderend, Hemel-en-Aarde, Villiersdorp, Paarl, Simondium, Stellenbosch and Somerset West in the Western Cape.

Based on experiences in other parts of the world, as well as the high rate of reproduction and short generation time of these flies, Brent Walsh, CEO of Berries ZA, said he expected SWD to spread to most fruit production regions by next season as eradication was impossible.

He added that the DALRRD still needed to engage industries on the conditions for movement of fruit of farms in regions where the fly is present.