As risk of hunger rises, three questions on the locust swarms
Normally, the life of a desert locust is lonely and short – out of sight, and for most of the world, out of mind.
Not this year. Since mid-2019, swarms have devastated farmlands across the Arabian Peninsula and East Africa, which is already one of the world’s most food-insecure regions. Today, more than 20 million people are at risk of going hungry, according to the United Nations.
Why We Wrote This
Some disasters seem so epic, so vast, that they almost seem out of our control. But human activity has played a hand in how quickly the locust crisis developed in East Africa – and can try to stop it before it multiplies again.
Images of swarms crowding the sky seem practically biblical, recalling the plague of locusts in the Book of Exodus. But some of the factors that caused today’s crisis, experts say, are far more earthly.
Fighting in Yemen and Somalia has made it difficult for governments or humanitarian organizations to kill the insects, and they are now crossing into South Sudan, whose instability could create similar challenges. Some experts also note that climate change is contributing to the extreme weather locusts thrive on.
“This crisis is both natural and man-made,” says Baldwyn Torto, at the International Centre of Insect Physiology and Ecology in Nairobi, Kenya. “There is a natural cycle of cyclones in this region, but there’s also so much insecurity in some parts of the region that the surveillance systems for locusts and other pests have broken down.”
The images are striking: millions of bright yellow locusts descending on farms and floating over cities in thick, dark mats – some of them several miles wide. Since mid-2019, record-setting locust swarms have devastated farmlands across the Arabian Peninsula and East Africa, where more than 20 million people currently risk going hungry as a result of the swarms.
To many, the swarms of today seem practically biblical, recalling the plague of locusts described in Exodus, “cover[ing] the face of the ground so that it cannot be seen.”
But these locust swarms have more earthly and modern reasons for being: a dangerous alchemy of bad weather and human conflict, which has created the rare circumstances needed for the locusts to cause widespread devastation.
Why We Wrote This
Some disasters seem so epic, so vast, that they almost seem out of our control. But human activity has played a hand in how quickly the locust crisis developed in East Africa – and can try to stop it before it multiplies again.
Why is this happening now?
In normal times, the life of a desert locust is lonely and short. They live, breed, and die mostly in isolated bands across a parched tract of land stretching across the Sahara desert in North Africa, the Arabian Peninsula, and northwest India – out of sight, and for most of the world, thoroughly out of mind.
But every so often, it rains in the desert, and when it does, deserts locusts multiply and migrate. That’s what began to happen in 2018, after two cyclones struck the Arabian Peninsula in quick succession, leaving behind stagnant pools of water that formed perfect locust breeding grounds. Within months, the population had swelled to many times its normal size and began to travel in search of food, carried by the winds – sometimes as quickly as 60 miles per day – toward Yemen and later, Somalia.
In both countries, the insects were helped along by violent conflict, which meant many of their breeding grounds were inaccessible to governments and humanitarian organizations looking to kill the insects before they hatched and spread. The swarms continued to grow, and have since spread across parts of Kenya, Ethiopia, Uganda, and Tanzania, where unusually heavy rains have given them potent new breeding grounds. They are now crossing into South Sudan, where instability and civil war will also make it difficult to stop their spread.
“This crisis is both natural and man-made,” says Baldwyn Torto, a principal scientist specializing in locusts at the International Centre of Insect Physiology and Ecology in Nairobi, Kenya. “There is a natural cycle of cyclones in this region, but there’s also so much insecurity in some parts of the region that the surveillance systems for locusts and other pests have broken down.” Other experts note that climate change is also contributing to the extreme weather locusts thrive on.
What do locust swarms do?
Mostly, they eat. A desert locust can eat its own body weight (about 2 grams) in vegetation every day. That means a swarm covering a square kilometer – which contains about 40 million locusts – can consume the same amount of food in a day as 35,000 people, according to the Food and Agriculture Organization (FAO) of the United Nations.
Across East Africa, swarms have decimated farms and grazing lands. That has left more than 20 million people at risk of hunger, the FAO warns, in a region that is already one of the most food-insecure. And when they are not eating, locusts are breeding. The current swarms have laid eggs across the region, and if they are not destroyed, experts say their numbers could grow 500-fold by June.
What can be done?
The most effective way to kill locusts is to spray them with pesticides from airplanes – optimally, before the locusts mature. But that’s difficult in the current crisis for many reasons.
For one, “these swarms are happening in countries that see locust swarms very rarely,” Dr. Torto notes, and therefore often lack the resources or technical expertise to combat them. For another, the locusts are still breeding in difficult-to-reach areas.
Finally, the FAO says it has received just $33 million of the $138 million it needs to clamp down on the locusts before regional harvests begin in April and May. The World Food Program says it will cost 15 times more to feed those whose food sources are destroyed by swarms than it will cost to prevent the swarms from forming now.
