The desert locust is one of the most devastating migratory pests in the world. It is highly mobile and feeds on large quantities of any kind of green vegetation, such as crops, pasture, and fodder. A typical swarm can be made up of 150 million locusts per square kilometer, usually carried by the wind up to 150km in one day. Even a very small, one-square-kilometer locust swarm can eat the same amount of food in one day as about 35,000 people. This poses a significant threat to subsistence farmers as the locusts destroy their very livelihood, and potentially endangers the food security of almost 25 million people.
A swarm covering an area the size of Luxembourg has been spotted in 10 African and Middle Eastern countries in the last few months, and more recently in Kenya. Experts fear that global warming is the root cause, and an increase in tropical storms is creating favourable conditions for them to breed in.\
So where did it start, and how do warming global temperatures facilitate longer breeding conditions?
As greenhouse gases trap more energy from the sun the oceans absorb more heat, resulting in an increase in surface sea temperatures. Changes in ocean temperatures and currents brought about by climate change lead to alterations in climate pattern around the world. Tropical cyclones are one example, and form when the water warms above 27°C, causing the moist air above the oceans to rise. In this case, a pair of cyclones came in from the Indian Oceans and targeted the Arabian peninsula - the vast desert region near the border of Saudi Arabia, Yemen, and Oman, which brought copious amounts of wind and rain.
When this rain falls in semi-arid and desert-like regions, the sandy soils are unable to cope with the amount of rainfall and inevitably flood. As such, once the floods recede, much of the soil retains this moisture, and according to the United Nations’ Food and Agriculture Organisation (UNFAO) provides perfect conditions for female desert locusts to lay their eggs for months at a time.
The desert locust are a difficult pest to control as they often cover very large and remote areas. But also, many countries affected lack basic infrastructure with limited resources for locust monitoring and control, and those inundated with political rife struggle to develop the necessary implementation activities. Without preventive systems, these locust swarms could happen more frequently, last longer, and spread further beyond imagination. The UN has warned that the locust swarms could increase 500 times by June, posing a major threat to the entire region.
The short food supply also presents another problem. As demand outstrips supply, the price for a kilogram of rice now costs more than £1 compared to 70p before the locust crisis. From the outset, this may not seem a lot, but for those with little money, no crops, and families to feed, this is a significant rise.
The locusts are causing significant disruption to the region’s food supply and raising prices in areas most heavily affected.
The biggest issue is that African countries such as Somalia, Ethiopia, and Kenya are already fragile with food security. If they don’t manage to get this locust invasion under control, and reduce the significant strain on the current food supply, then they could potentially face a severe famine like Ethiopia has continually experienced over the twentieth century.