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What Happened to Locusts?

Locusts are a type of short-horned grasshopper that can transform from a solitary phase into a gregarious, swarming phase under specific environmental conditions, leading to devastating plagues that consume vast amounts of vegetation. The early 2020s saw a major Desert Locust upsurge in East Africa and Yemen, exacerbated by climate change, which severely threatened food security. While that upsurge was largely suppressed by early 2022, new outbreaks have emerged in Northwest Africa, Namibia, and Australia in 2025 and 2026, prompting ongoing surveillance and control efforts.

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Quick Answer

Locusts are grasshoppers that, when conditions are right (often after heavy rains leading to abundant vegetation and subsequent crowding), undergo a behavioral and physiological transformation, forming massive, destructive swarms. After a major crisis in East Africa and Yemen from 2019-2021, largely brought under control by 2022, new outbreaks have been reported in Northwest Africa (Morocco, Algeria, Tunisia, Libya) since late 2024, continuing into May 2026. Additionally, increased Australian plague locust activity was noted in South Australia in May 2026, and desert locust outbreaks in Namibia in May 2026, highlighting the persistent global threat these pests pose to agriculture and food security.

📊Key Facts

Peak affected population (East Africa & Yemen, 2020)
Nearly 40 million people at risk of food insecurity
ReliefWeb, 2021; FoodUnfolded, 2020
Worst outbreak for Kenya (2020)
70 years
FAO, 2020; ReliefWeb, 2022
Worst outbreak for Ethiopia & Somalia (2020)
25 years
FAO, 2020; ReliefWeb, 2022
Crop loss prevented by control operations (East Africa, 2020)
1.5 million metric tons
ReliefWeb, 2020
Area treated by FAO & partners (East Africa & Yemen, 2020-2021)
Over 2 million hectares
FAO, 2022
Estimated population per square kilometer in a swarm
Up to 150 million locusts
Courthouse News, 2020
Food consumption by an average swarm (1 sq km)
As much as 35,000 people can eat in a day
Courthouse News, 2020; ScienceDaily, 2024

📅Complete Timeline15 events

1
October 2019Critical

East Africa Desert Locust Upsurge Begins

Unusual heavy and widespread rains in late 2019, linked to cyclones in the Indian Ocean, create ideal breeding conditions, leading to a significant Desert Locust outbreak in the Horn of Africa.

2
January 24, 2020Critical

FAO Warns of Worst Outbreak in Decades

The FAO declares the Desert Locust situation in East Africa as the worst in 25 years for most affected countries, and 70 years for Kenya, posing a serious threat to food security and livelihoods.

3
February 18, 2020Critical

Swarms Spread Across East Africa

Locust swarms spread to eight countries in East Africa, including Kenya, Ethiopia, Somalia, Djibouti, Uganda, Tanzania, Sudan, and Eritrea, with a high risk of reaching South Sudan and the Democratic Republic of Congo.

4
May 29, 2020Major

Swarms Reach India and Pakistan

Locust swarms originating from the Arabian Peninsula invade parts of India and Pakistan, causing significant crop damage, with India estimating over 200,000 hectares affected.

5
October 9, 2020Major

Infestations Persist in Ethiopia and Somalia

FAO reports that desert locust infestations are expected to persist in Ethiopia and Somalia through at least March 2021, with Yemen remaining a significant breeding reservoir.

6
March 10, 2021Major

Climate Change Link Highlighted

Scientists and organizations, including the Global Landscapes Forum and FAO, draw links between the increased frequency and intensity of locust outbreaks in the Horn of Africa and climate change, particularly powerful cyclones.

7
February 16, 2022Critical

East Africa Upsurge Declared Suppressed

After extensive control operations and significant international support, the FAO announces that the Desert Locust upsurge in East Africa and Yemen has been largely suppressed.

8
December 20, 2024Notable

New Predictive Tool Developed

The University of Cambridge develops a new tool that uses weather forecast data and computational models to predict desert locust swarm behavior, aiming to improve early warning and control.

9
March 30, 2025Major

FAO Warns of Northwest Africa Outbreak

The FAO issues a warning about a potential Desert Locust outbreak in Morocco, as swarms, fueled by heavy rains in late 2024 and rising temperatures, spread across central Algeria, western Libya, and southern Tunisia.

10
July 3, 2025Major

Significant Outbreaks in North Africa

Significant Desert Locust outbreaks are reported in Algeria, Tunisia, Libya, and Saudi Arabia, with smaller bands appearing elsewhere across the Sahara Desert's northern boundary, due to favorable breeding conditions.

11
January 24, 2026Major

Soil Health Improves Locust Control

Scientists working with farmers in Senegal demonstrate that enriching soil with nitrogen can dramatically reduce locust damage to crops and double yields, offering a new sustainable control method.

12
March 6, 2026Major

Outbreak Continues in Western Sahara and Morocco

The serious Desert Locust outbreak continues in Western Sahara and southern Morocco, with adult groups increasing and moving northward, reaching the Canary Islands and Algeria.

13
May 26, 2026Notable

Locust Outbreak in Namibia

A Desert Locust outbreak is detected in parts of Namibia's Erongo and Hardap regions, with swarms destroying grazing and natural vegetation, prompting deployment of control teams.

14
May 27, 2026Notable

Australian Plague Locust Activity Increases

Following record-breaking rainfall in February 2026, Australian plague locust activity increases across parts of South Australia, with low- to medium-density populations present.

15
May 31, 2026Major

Ongoing Monitoring and Breeding Forecasts

The FAO's May 2026 Desert Locust Bulletin reports continued breeding in Morocco, increasing hopper groups and bands, and forecasts small-scale spring breeding in Tunisia, Libya, Egypt, Oman, Saudi Arabia, Somalia, and Yemen, requiring ongoing surveillance.

🔍Deep Dive Analysis

Locusts are specific species of short-horned grasshoppers (family Acrididae) that exhibit a unique phenomenon called phase polyphenism. Normally solitary, they undergo dramatic changes in behavior, morphology, and physiology when their populations become dense due to favorable environmental conditions, typically heavy rainfall followed by lush vegetation. This crowding triggers a release of serotonin, making them gregarious, increasing their mobility, and altering their appetite, leading to the formation of massive, highly destructive swarms. These swarms can contain billions of insects, cover hundreds to thousands of square kilometers, and consume their own body weight in food daily, devastating crops and pastures.

The most significant recent event was the Desert Locust upsurge that began in late 2019 and ravaged the Greater Horn of Africa and Yemen through 2021. This outbreak was the worst in 25 years for Ethiopia and Somalia, and 70 years for Kenya, putting nearly 40 million people at risk of food insecurity. The crisis was largely attributed to unusual weather and climate conditions, particularly powerful cyclones in the western Indian Ocean in 2018 and 2019, which dumped heavy rains in arid breeding grounds in the Arabian Peninsula. These conditions created vast areas of green vegetation, fueling rapid locust multiplication and spread across the Red Sea into East Africa.

Key turning points included the rapid escalation of the crisis in early 2020, prompting the Food and Agriculture Organization (FAO) of the United Nations to launch a massive, coordinated response. Despite challenges like the COVID-19 pandemic and regional insecurity, extensive aerial and ground control operations were implemented. By early 2022, with significant international support, the FAO declared the upsurge in East Africa and Yemen largely suppressed, preventing an even greater humanitarian disaster.

However, the threat of locusts remains persistent. Since late 2024, and continuing into 2025 and 2026, new outbreaks have emerged in Northwest Africa. Unusually heavy rains in late 2024 and rising temperatures in early 2025 created ideal breeding conditions in the Sahel and southern Sahara, leading to significant infestations in Algeria, Tunisia, Libya, and Morocco. The FAO has issued caution-level alerts for these regions, emphasizing the need for sustained surveillance and rapid control to prevent further spread.

As of May 31, 2026, Desert Locust activity continues in Western Sahara and southern Morocco, with hopper groups and small bands increasing, and breeding observed in Algeria. Small-scale spring breeding is also anticipated in Tunisia, Libya, Egypt, Oman, Saudi Arabia, Somalia, and Yemen. In other parts of the world, a desert locust outbreak was detected in Namibia's Erongo and Hardap regions in May 2026, destroying grazing and natural vegetation. Additionally, Australian plague locust activity increased in South Australia in May 2026 following record rainfall in February, with potential for further population increases later in the year. Research in 2026 also highlighted new control methods, showing that improving soil health with nitrogen can make crops less appealing to locusts, reducing damage and doubling yields.

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People Also Ask

What are locusts?
Locusts are certain species of short-horned grasshoppers that can change their behavior and physiology under specific environmental conditions, transitioning from a solitary phase to a gregarious, swarming phase. This transformation leads to the formation of massive, destructive swarms.
Why do locusts form swarms?
Locust swarms form primarily due to high population density, often triggered by heavy rainfall in arid areas that leads to abundant vegetation. This crowding causes physiological and behavioral changes, making the locusts more sociable, mobile, and voracious, leading them to aggregate into large swarms.
Which regions have been most affected by locust outbreaks recently?
From 2019-2021, the Horn of Africa and Yemen experienced the worst Desert Locust upsurge in decades. More recently, since late 2024 and continuing into 2026, Northwest Africa (Morocco, Algeria, Tunisia, Libya) has seen significant outbreaks. Namibia and Australia have also reported increased locust activity in May 2026.
How do locust swarms impact food security?
Locust swarms pose a severe threat to food security by consuming vast amounts of crops and pastureland. A single square kilometer swarm can eat as much food in a day as 35,000 people, leading to widespread crop destruction, livelihood losses for farmers and pastoralists, and exacerbating food crises in affected regions.
What is being done to control locust outbreaks?
Control efforts primarily involve extensive surveillance, early warning systems, and aerial and ground spraying of insecticides. International organizations like the FAO coordinate responses, provide technical expertise, and support affected countries. Recent research also explores sustainable methods like improving soil health to make crops less appealing to locusts.