Kenya's locust outbreak is the worst experienced by the country in 70 years (Credit:

Since the beginning of 2020, the East African country of Kenya has been battling the nation's worst desert locust outbreak in over 70 years. The destructive swarms, some as big as three times the size of New York City — an estimated 192 billion insects — are eating their way through thousands of acres of crops and animal pastures, decimating livelihoods in the process. Even worse, the locusts, which arrived from neighboring Somalia and Ethiopia, are now spreading to other countries, including Uganda, South Sudan, Tanzania, and Congo.

"These things are voracious," says Keith Cressman, the UN Food and Agriculture Organization's (FAO) senior locust forecasting officer. "A swarm the size of Manhattan can, in a single day, eat the same amount of food as everyone in New York and California combined."

What caused East Africa's enormous locust outbreak?

Locusts can multiply rapidly and cause large-scale devastation if left unchecked (Credit: Christiaan Kooyman /public domain/

Desert locusts, or Schistocerca gregaria, are notorious for their ability to breed rapidly — every three months — and in large numbers. They can also remain airborne for hours and, with some help from the wind, travel as much as 80 miles (130 km) a day. Most years, the insects stay confined to deserts in Africa, the Near East, and Asia. However, under the right environmental conditions, the insects can multiply swiftly — as much as 400 times every six months — and cause havoc worldwide. According to FAO, previous infestations have extended to as many as 60 countries!

"It's a pest that has been around for eons and eons of time," Cressman says. "It has so many different survival mechanisms ... to just survive in some of the harshest areas and most remote parts of this planet. But it has this fabulous capacity to take advantage of good conditions."

The "good conditions" the scientist is referring to began in mid-2018 when a freak cyclone from the Indian Ocean struck a remote area of the Arabian Peninsula known as the "Empty Quarter." Normally, the Empty Quarter would dry out within a short period, killing most of the locust population, which depends on green plants for food. However, in late 2018, a second cyclone struck the same region. The extra food supply caused the population to explode for the second time in six months. "That was just a huge sandy area that got wet by these extraordinary rains. And this is exactly what desert locusts need in order to lay their eggs and to breed," Cressman says.

Kenya's locust infestation has spread rapidly across the country since early January 2020 (Credit:

Over the next three months, the insects began to migrate. While some spread further out on the Arabian Peninsula, others let the winds carry them into nearby Yemen, and then across the gulf into Ethiopia and Somalia. As luck would have it, yet another cyclone swept through Somalia and eastern Ethiopia, providing more food for the locusts to munch upon and allowing them to breed a new generation. Since neither country did anything to control the pests, the insects kept increasing and eventually crossed over to Kenya, where they once again met with favorable conditions, thanks to high amounts of unseasonal rain in the northern part of the country.

Cressman, who attributes the unusual cyclone activity to climate change, says, "If this trend continues, if there's an increased frequency of cyclones in the Indian Ocean, it's quite obvious that there will be an increased frequency of desert locust outbreak and upsurges like the one we're seeing now in the Horn of Africa."

What can be done to stop the current outbreak?

The locust outbreak can easily be curtailed by spraying the infested areas with pesticides (Credit: ChriKo /CC BY-SA 3.0,

Experts say the locusts are easy to control with pesticides. However, the efforts have been hindered, initially by the difficulty of implementing preventative measures in the conflict-ridden Yemen and Somalia, and more recently, by a lack of resources to battle such large numbers in Kenya and Ethiopia. Kipkoech Tale, a migratory pest control specialist with Kenya's Ministry of Agriculture, says the country needs more spraying equipment to supplement the four planes currently being used, as well as a steady supply of pesticides to effectively fend off the massive insect invasion.

If left unchecked, the locusts, which are actively breeding in Kenya, could grow 20-times the current number by March. The vast increase would coincide with the start of the country's planting season. "That means when farmers are planting, they will have the potential to be surrounded by an awful lot of hungry swarms," Cressman says. This could delay planting season and impact the farmers' food security and livelihoods. Even worse, the expert believes that if the control efforts fail, yet another generation of locusts, which have a lifespan of between three to five months, could emerge just in time for the September harvest season.

If more measures are not taken, the locust outbreak could get worse (Credit:

"We do have a chance to nip this problem in the bud, but that's not what we're doing at the moment," says Mark Lowcock, FAO's top humanitarian official. "We're running out of time." Hopefully, leaders worldwide will recognize the emergency and contribute generously towards the $138 million needed to control the locust outbreak.