Carried on monsoon winds across the Red Sea, vast swarms of desert locusts have posed a deadly threat to the people of the Horn of Africa for millennia. One swarm can number billions of insects, cover a 1,000-square-mile area and consume 30–40,000 tonnes of food per day — all of which makes the desert locust well deserving of its collective noun ‘plague’.
Much brain-power has been dedicated to the controlling of these insects, whose swarms can lead, and have led to, famines. Methods of control have included the digging of trenches to catch hoppers (juvenile locusts) and, later, the aerial spraying of chemical and fungal insecticides. In the early 1950s, however, laying poison-laced bran in the path of marching hoppers was the method most commonly used.