A newly developed tool designed to forecast the behavior of desert locust populations will greatly assist national authorities in managing large swarms before they can destroy food crops in Africa and Asia.
Desert locusts usually live alone until certain factors, such as heavy rainfall, prompt them to gather in large swarms, which can have disastrous effects.
This migratory pest can multiply rapidly, and a swarm that covers just one square kilometer can devour enough food in a single day to feed 35,000 individuals. Such substantial agricultural damage can drive up local food prices and potentially result in riots and widespread hunger.
Now, a research team led by the University of Cambridge has created a method to forecast when and where desert locusts will form swarms, allowing interventions before the situation escalates.
This approach utilizes weather prediction data from the UK Met Office alongside advanced computational models of the locusts’ aerial movements to anticipate where swarms will gather as they look for new feeding and breeding locations. Areas predicted to be impacted can be pre-treated with pesticides.
According to the researchers, past methods for predicting and managing locust swarms have been unpredictable. Their new model, which was published today in the journal PLOS Computational Biology, enables national organizations to react swiftly to emerging locust threats.
Controlling desert locusts is crucial for maintaining food security; they are one of the biggest migratory pests affecting small-scale farmers across many parts of Africa and Asia, with the ability to travel long distances across borders.
Climate change is likely to increase the frequency of desert locust swarms by creating more trigger events, such as cyclones and heavy rains. These conditions introduce moisture into arid areas, fostering plant growth that feeds locusts and stimulates their reproduction.
“During an outbreak of desert locusts, we can now forecast where swarms are likely to go several days ahead, allowing us to manage them at specific locations. If we fail to control them at these sites, we can predict their next movements, enabling preparations in those areas,” explained Dr. Renata Retkute, a researcher in the University of Cambridge’s Department of Plant Sciences and the first author of the study.
“The key is to act quickly if a significant locust surge is anticipated, stopping it from causing serious crop damage. Large swarms can lead to dire situations where communities might face starvation,” added Professor Chris Gilligan from the same department, who is the senior author of the paper.
He further stated: “Our model will ensure that we’re ready to act immediately in the future, rather than having to start over, which has often been the case historically.”
The need for a detailed model of desert locust behavior became apparent during the response to a significant surge between 2019 and 2021, which stretched from Kenya to India and severely impacted wheat production in these areas. These infestations caused widespread destruction of sugarcane, sorghum, maize, and root vegetables. The researchers noted that previous scientific responses were hindered by the requirement to collect and consolidate information from various sources.
“The reaction to the latest locust surge was highly improvised, and less effective than it could have been. We’ve developed a thorough model that can be utilized in future outbreaks to manage this destructive pest,” said Retkute.
Although similar models have been attempted in the past, this is the first that can quickly and accurately predict swarm behaviors. It considers the lifecycle of the insects and their choices for breeding sites, allowing forecasts of locust swarm movements in both the short and long term.
The new model has undergone rigorous testing with real surveillance and weather data gathered during the last significant locust surge. It aims to enhance surveillance, provide early warnings, and improve the management of desert locust swarms by national governments and international organizations like the Food and Agriculture Organization of the United Nations (FAO).
Researchers indicate that nations which have not experienced a locust outbreak in many years are often ill-equipped to respond effectively, lacking the essential surveillance personnel, aircraft, and pesticide resources. As climate change reshapes the patterns and spread of large swarms, improved preparedness is vital — making the new model a timely and necessary innovation.
