From bark beetles to fall armyworms to plagues of locusts, when insects band together they can do immeasurable damage to crops and as a result our food security. Meet some of the biggest little offenders.
Maize crops in South Africa and Zimbabwe face a new danger in the form of the fall armyworm. It has long proved a challenge to farmers in both north and south America, but its presence in Africa was first recorded a year ago when it appeared in Sao Tome and Principé.
The Center for Agriclture and Biosciences International (CABI), which has many offices around the world, has warned that the pest, which sustains itself by eating crops such as maize, could spread to Asia and the Mediterranean in the medium-term, posing a "major threat to agricultural trade worldwide."
Godfrey Chikwenhere from Zimbabwe's Agriculture Ministry told the dpa newsagency that the little pest, which was first detected in the county in December last year, had spread to all provinces by the middle of last month. Though he said the crop most affected was maize, he said yield reduction had so far been minimal.
"We are still in the reach of controlling the pest," he said. "We have deployed teams to spray affected areas."
South Africa says it too has developed an emergency response plan to deal with the pest, which includes awareness campaigns and pesticide trials.
It is believed the fall armyworm was transported to Africa on commercial planes.