A man holds a desert locust in his hand in Kenya's Rift Valley. Farmers in central Kenya fear the locusts will strip vegetation from the rangeland where their livestock graze.

A man holds a desert locust in his hand in Kenya's Rift Valley. Farmers in central Kenya fear the locusts will strip vegetation from the rangeland where their livestock graze. / Getty Images

Aid agencies report swarms of locusts have been descending on farms in northern Kenya, destroying crops and even leaving pastures bare of vegetation.

The UN's Food and Agriculture Organization in a regional update on the pests says swarms have been detected this week in seven counties in Kenya compared to just four a week ago.

Across the Horn of Africa locust invasions have reached dangerous levels in Ethiopia, Somalia and Kenya, according to the FAO.

"For Kenya this is a second wave," Hamisi Williams FAO deputy country representative for Kenya told Spice FM in Nairobi. "The first wave came in 2020 and we dealt with it." Kenya attacked the locusts with insecticides both from individual farmers on the ground and aerial spraying from planes. But other countries in the region — ones with fewer resources and wracked by conflict including Somalia, Yemen and Ethiopia — didn't go after the bugs as aggressively.

"A lot of (locust) breeding happened in Ethiopia for the entire 2020. The same situation happened in Somalia," Williams said. "We are now suffering the fate of our neighbors who just didn't do a good job for one reason or the other," in controlling the desert-dwelling grasshoppers.

As locusts by the billions descend on parts of Kenya in the worst outbreak in 70 years, small planes are flying low over affected areas to spray pesticides in what experts call the only effective control.

As locusts by the billions descend on parts of Kenya in the worst outbreak in 70 years, small planes are flying low over affected areas to spray pesticides in what experts call the only effective control. / AP

But he concedes that part of the reason the locusts reproduced so rapidly was because of unusual rainfall patterns.

"We saw very intense rainfall in areas of northeastern (Kenya), where normally it's very dry," Williams said. "Normally there would be nothing there for locusts to feed on. They wouldn't be able to survive there for long." But that wasn't the case last year. "And you got so much fodder which the locusts were able to feed on, and they were able to breed."

The Famine Early Warning System says that several parts of the Horn of Africa currently are facing food crises driven in part by the surge in swarms of desert locusts. The warning system originally created by the U.S. Agency for International Development predicts the lack of adequate food will get even worse in the coming months. The areas expected to deteriorate the most are Ethiopia, Sudan and Yemen.

Keith Cressman, the senior locust forecasting officer at the FAO based in Rome calls the desert locusts which are currently plaguing the region "professional survivalists." He says these insects "are living in some of the harshest parts of the world. They're living in the Sahara desert, in the deserts of Arabia and southwest Asia. And when the rains do fall they have this capacity to take advantage of those exceptional occasions and reproduce very, very rapidly."

Over a three month period a swarm of locusts can multiply 20 fold, Cressman says.

"The other thing is that they have this great capacity to migrate. So they don't get stuck in areas when conditions dry out. They just simply pick up and move to greener pastures," he says. They fly with the wind and can travel more than 100 miles in a day.

"They can easily cross the Red Sea so they can go from Sudan to Saudi Arabia in a day, for example," Cressman says of the biblical pests. "They can easily cross from northern Somalia directly across the Indian Ocean to India and Pakistan."

And when they arrive somewhere, they're incredibly destructive, ravenously devouring vegetation.

"Imagine a swarm the size of Manhattan in New York, which is not a very big swarm," he says. "That single swarm in one day will eat the same amount of food as everybody in New York and California."

For local farmers, the arrival of a cloud of locusts can spell doom. Since last year, FAO has helped to set up a fleet of 28 aircraft in Kenya, Somalia and Ethiopia. The planes both spot for swarms and carry out aerial spraying against them.

"We're not trying to exterminate the locusts, or eliminate them completely," Cressman says. "We are just trying to bring them down to lower levels. Then natural predation, natural diseases, will manage the locusts as they normally do in most years." But adding to the current woes of the region, even the funding for those aircraft is in danger of drying up.

The FAO Deputy Director-General Laurent Thomas is asking for an additional $40 million dollars to support the operation. "The last time Africa saw an upsurge of locusts approaching this scale, in the Sahel, it took two years and more than $500 million to bring under control," Thomas said Tuesday in a statement. "This (current) upsurge was even bigger, but East Africa is poised to end it — provided governments can keep those aircraft flying."

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