Desert locust upsurge subsides after the 2019-2021 crisis but FAO warns of persistent risk in the Horn of Africa and Arabian Peninsula as breeding conditions remain favorable

Summary

The desert locust (Schistocerca gregaria) crisis of 2019-2021 was the most severe in East Africa and the Arabian Peninsula in 70 years, destroying crops worth an estimated $8.5 billion across East Africa, Yemen, India, and Pakistan. By 2022, FAO declared the upsurge officially controlled following extensive aerial spraying campaigns. However, FAO's Desert Locust Watch documented continued low-level breeding activity in Somalia, Ethiopia, and Sudan through 2024-2025, with a spring 2025 breeding surge in the Arabian Peninsula requiring emergency aerial and ground spraying operations in Yemen, Saudi Arabia, and Oman. Climate researchers have identified the 2019-2021 upsurge as partly driven by unusual cyclone activity in the Arabian Peninsula in 2018, creating breeding habitat in normally barren areas, and warned that climate change is increasing the frequency of the rainfall anomaly events that trigger locust population explosions.

The split

FAO and national plant protection organisations in affected countries framed the post-2021 locust situation as a success story in early warning and coordinated response, arguing that the EMPRES system and rapid aerial spraying prevented the 2024-2025 Arabian Peninsula surge from becoming a new upsurge comparable to 2019-2021. Agricultural and environmental researchers argued that the success was contingent on continued surveillance investment and that surveillance capacity in the conflict-affected areas of Yemen, Sudan, and parts of Somalia, which are often the initial breeding sites for the largest upsurges, remained dangerously degraded. Climate scientists warned that the 2019-2021 event was a preview of more frequent and severe locust crises as climate change increases extreme rainfall variability in the locust breeding belt.

By the numbers

• $8.5 billion: crop and pasture losses from the 2019-2021 East Africa/Yemen/South Asia desert locust crisis
• 70 years: how long East Africa had not seen a locust crisis of comparable severity before 2019
• 2022: year FAO declared the 2019-2021 upsurge officially controlled
• Spring 2025: new breeding surge in the Arabian Peninsula requiring emergency response
• Affected 2019-2021: Kenya, Ethiopia, Somalia, Eritrea, Djibouti, Sudan, Uganda, Tanzania, Yemen, India, Pakistan
• 2018 Cyclones Mekunu and Luban (Arabia): primary trigger for the 2019-2021 upsurge

Why it matters

The desert Locusts threat is one of the world's most acute food security risks because desert locust swarms can travel up to 150 km per day and a single swarm of one square kilometre contains approximately 40 million locusts that consume as much food per day as 35,000 people. The locust belt, spanning from West Africa through East Africa, the Arabian Peninsula, and South Asia to India and Pakistan, overlaps with some of the world's highest concentrations of food-insecure populations and some of the most conflict-affected countries, including Yemen, Sudan, Somalia, and Eritrea. Climate change-driven increases in the frequency of the triggering rainfall events represent a structural upward shift in the locust risk baseline that will require sustained investment in EMPRES early warning, surveillance, and rapid-response capacity to manage.

What to watch

• FAO Desert Locust Watch monthly situation reports for Horn of Africa and Arabian Peninsula through the 2026 spring breeding season
• Whether the 2025 Arabian Peninsula surge generates any long-distance swarm movements toward East Africa or South Asia
• How Sudan's civil war (ongoing since April 2023) is affecting ground surveillance capacity in Sudanese locust breeding zones
• Whether donors sustain FAO EMPRES funding at the post-2019 enhanced levels or revert to pre-crisis underfunding