Farmer's Weekly (South Africa)
Quelea outbreaks threaten Zimbabwe’s maize crop
Large outbreaks of red-billed queleas ( Quelea quelea) pose a serious threat to maize plantings in Zimbabwe, especially for young maize in the soft-dough stage.
The Zimbabwean Plant Protection Research Institute has called on landowners and farmers to report outbreaks when detected to ensure that control measures are put in place in good time.
According to a recent report in The Herald newspaper in Zimbabwe, the outbreaks had occurred in all of that country’s maize production areas. In the report, the head of the institute, Shingirai Nyamutukwa, confirmed that the institute “had more than enough chemicals to combat the outbreaks”.
Nyamutukwa added that Zimbabwe had acquired about 7 400ℓ of chemicals to deal with the birds. The country normally bought 5 000ℓ, which lasted up to three seasons. He called on farmers with large tracts of land to identify the roosting sites and alert the authorities as soon as possible so that control measures could be taken early, as the birds were entering their breeding season.
Dr Gerhard Verdoorn, operations and stewardship manager at CropLife South Africa, told Farmer’s Weekly that the outbreaks in Zimbabwe did not pose a danger to local crops, as the queleas in that country were from a different subpopulation than those in South Africa.
He said queleas had been a threat to summer subsistence grain crops in Zimbabwe for many years.
“The outbreaks in Zimbabwe often reach cataclysmic proportions and can [result in] hunger among the local population. Quelea swarms of more than three million birds are not unknown in Southern Africa.
“I witnessed a swarm of at least 3,5 million birds devouring 40ha of irrigated wheat in 15 minutes,” Verdoorn said.
He did not expect serious crop damage from queleas in South Africa because of the good rainfall and the ample supply of natural food for them. “Queleas prefer wild seeds to crops, and will only feed on crops during times of [need].” – Annelie Coleman