A Very, Very Hungry Caterpillar Is Wreaking Havoc on Africa’s Crops

Fall Armyworm
The fall armyworm is native to the Americas, but has quickly invaded southern Africa and is wreaking havoc on crops there. Kansas State University, Department of Entomology

The fall armyworm is a small, unassuming caterpillar that grows to just 1.5 inches long. But this little creature, as its name suggests, is capable of causing widespread destruction. Reporting for Nature, Sarah Wild writes that the fall armyworm has been chomping its way through crops in southern Africa, posing a threat to both food security and agricultural trade.

This voracious pest, which is the larval form of the fall armyworm moth, originates in Central and South America. It is believed to have arrived in Africa last year, and it may have spread to as many as seven different countries in that time, reports Matthew Hill of the Chicago Tribune. Experts estimate that the fall armyworm has already mowed through at least 700,000 acres of maize, millet, and sorghum crops in Africa. According to the FAO, it can destroy up to 73 percent of a given field, and it “is difficult to control with a single type of pesticide."

The invasion of the fall armyworm is, naturally, causing considerable panic among African officials. According to Sifelani Tsiko of The Southern Times, plant and animal disease experts held an emergency meeting in Harare, Zimbabwe this month to address the growing crisis. Officials are deeply concerned about potential food shortages, as the fall armyworm has been destroying staple crops. The southern region of the continent, which is still recovering from a two-year drought, is at particularly high risk.

“If [the fall armyworm] persists, the consequences for Africa will be severe,” Ken Wilson, a professor of ecology at Lancaster University in Britain, said during the meeting, according to Tskio.

Nobody knows how the fall armyworm travelled from the Americas to Africa, but scientists believe that the caterpillar—or its eggs—may have arrived with imported produce, the BBC’s Helen Briggs reports. The presence of the caterpillar has been confirmed in Ghana, South Africa, Zambia, and Zimbabwe, according to Hill at the Chicago Tribune. There are reports that the fall armyworm has also reached Malawi, Mozambique and Namibia.

If it continues to proliferate, the fall armyworm will likely move into Europe and Asia, causing even more destruction. The pest has been well studied in South and Central America—Brazil, for example, spends $600 million every year controlling infestations—but little research has been done on its behavior in different regions. So a team of African researchers has banded together to study the fall armyworm: how it responds to insecticide, how it behaves on different crops, how it fares in different climates. As scientists learn more about the behavior of the fall armyworm, they may be able to stop this very hungry caterpillar in its tracks.

Get the latest stories in your inbox every weekday.