Extreme wind and rain may produce larger and more severe desert locust outbreaks, with human-caused climate change likely to exacerbate weather patterns and increase outbreak risks, according to a recent study.
The desert locust, a short-horned insect found in some dry areas of northern and eastern Africa, the Middle East, and South Asia, is a migratory bug that infests crops in swarms and causes hunger and food poverty.
A square kilometer swarm contains 80 million locusts capable of devouring enough food crops to serve 35,000 people in a single day. The U.N. Food and Agriculture Organization calls it “the most destructive migratory pest in the world.”
According to a study published in Science Advances on Wednesday, these outbreaks will become “increasingly difficult to prevent and control” as the temperature warms.
The study’s author, Xiaogang He, an assistant professor at the National University of Singapore, believes that more frequent and severe extreme weather events caused by climate change could increase the unpredictability of locust outbreaks.
However, he hoped that the study would assist countries in understanding and addressing “the impacts of climate variability on locust dynamics, particularly in the context of its repercussions on agricultural productivity and food security” and urged better regional and continental cooperation among countries and control organizations to respond quickly and build early warning systems.
Scientists used the Food and Agriculture Organization’s Locust Hub data tool to investigate incidences of desert locust outbreaks from 1985 to 2020 throughout Africa and the Middle East, as well as their relationship to climate change.
They developed and applied a data-driven framework to investigate the patterns of insects in order to determine what causes outbreaks to occur over great distances.
They discovered that ten countries, including Kenya, Morocco, Niger, Yemen, and Pakistan, saw the most of locust outbreaks among the 48 impacted countries.
The biggest outbreak of desert locusts in 25 years hit East Africa in 2019 and 2020, destroying hundreds of thousands of acres of farmland and damaging crops, trees, and other vegetation, jeopardizing food security and livelihoods.
Elfatih Abdel-Rahman, a scientist at the International Centre of Insect Physiology and Ecology who was not involved in the study, said widespread desert locust outbreaks caused by climate change will significantly threaten livelihoods in affected regions due to reduced food production and rising food prices.
The researchers discovered a close relationship between the severity of desert locust outbreaks and weather and land factors such as air temperature, precipitation, soil moisture, and wind. Desert locusts are more likely to infest dry places that get rapid, heavy rainfall, and the number of insects in an epidemic is heavily influenced by weather.
El Nino, a recurring and natural climate phenomena that impacts weather worldwide, was also closely linked to larger and more severe desert locust outbreaks.
Douglas Tallamy, an entomology professor at the University of Delaware who was not involved in the study, stated that irregular weather and rainfall cause spikes in vegetation, fueling massive population expansion in locusts.
“As such variability increases, it is logical to predict that locust outbreaks will increase as well,” Tallamy added.
The study is “yet another example of what should be a very strong wake-up call that societies across the globe need to come together to reduce climate change and its impacts, but also to implement strategies in response to global events such as increasing threats of desert locusts,” said Paula Shrewsbury, an entomology professor at the University of Maryland. Shrewsbury was not included in the study.
The study discovered that locust habitats in particularly vulnerable areas, such as Morocco and Kenya, have expanded since 1985 and are expected to rise by at least 5% by the end of the twenty-first century, primarily in west India and west Central Asia.
It uses the Rub’ al Khali, or Empty Quarter, a desert in the southern Arabian Peninsula, as an example of a site where desert locust outbreaks were once uncommon but have since become a hotspot. In 2019, the desert saw locust outbreaks as a result of unrestricted breeding caused by cyclones that inundated the desert with freshwater lakes.
Major locust outbreaks can have a significant financial impact. According to the World Bank, it cost more than $450 million to respond to a locust infestation in West Africa between 2003 and 2005. According to the report, the outbreak caused crop damage worth an estimated $2.5 billion.
Countries affected by desert locust outbreaks are already dealing with climate-related extremes such as droughts, floods, and heat waves, and the potential escalation of locust threats in these locations may exacerbate current issues, according to report author Xiaogang.
“Failure to address these risks could further strain food production systems and escalate the severity of global food insecurity,” he added.