Swarms of locusts can migrate
Swarms of locusts can migrate great distances and have even been observed twelve hundred miles at sea. The swarms can reach great sizes: a swarm across the Red Sea in 1889 was estimated to cover two thousand square miles. A swarm is estimated to contain up to 120 million insects per mile. (Raymond Dillard, The Minor Prophets, “Joel,” p. 255-56).