Drought causes moth torrent; insecticides will worsen it

After a flurry of photos of moths being posted on the Benoni City Times Facebook page, we found a possible explanation for the large number of the insects in Ekurhuleni.

People posted photos of insects in their homes.

According to Peter Webb, marketing officer of the Lepidopterists’ Society of Southern Africa, this is the normal time for them to be flying around.

“The general feeling from other lepidopterists is that as a result of the two previous very dry seasons, they are now out in abundance,” the expert said.

“Butterflies and moths are able to lay dormant as a pupa until conditions are ideal, remembering that there has to be enough plant material for their caterpillars to feed on.”

Webb’s comment was furthered by Hermann Staude, also from the Lepidopterists’ Society of Southern Africa.

Staude said: “One must understand that they go through several generations in one season.”

“This year has been a bumper year for them due to the recent good rains that have allowed them to increase their numbers significantly.

“This usually happens after a drought period because the moths can increase their numbers more rapidly than what their parasitoids (which normally keep the moths’ numbers in check) can do after a drought.

“Parasitoid numbers will soon increase as well and everything will return to normal.

If you spray insecticides you will actually harm the parasitoids even more and you will exacerbate the situation and it will take longer for things to return to normal.

“Best is to let nature run its course.”