A Devastating Insect Locusts are highly mobile,and usually fly with the wind at a speed of about 15-20 km/h.Swarms can travel about 5-130 km or more in a day. Locust swarm sizes can vary from less than one square kilometer to several hundred square kilometers with 40 to 80 million locusts per square kilometer. >An adult locust can consume its own weight in fresh food per day.A Devastating Insect A Devastating Insect ¾ Locusts are highly mobile, and usually fly with the wind at a speed of about 15-20 km/h. Swarms can travel about 5-130 km or more in a day. ¾ Locust swarm sizes can vary from less than one square kilometer to several hundred square kilometers with 40 to 80 million locusts per square kilometer. ¾ An adult locust can consume its own weight in fresh food per day