National Geographic : 2010 Feb
Sooty shearwater 40,000 miles Globe skimmer dragonfly 11,000 miles Leatherback turtle 12,700 miles Humpback whale 5,100 miles Monarch butterfly 4,300 miles One generation PHOTO: FORREST MITCHELL AND JAMES LASSWELL GRAPHIC: OLIVER UBERTI, NG STAFF W ILDLIFE An Epic Journey Every October millions of dragonflies--- mostly the widespread species known as the globe skimmer---begin to arrive in the Maldives, more than 300 miles southwest of India. By year's end the insects have gone, only to reappear briefly in May. Where do they come from? And where are they headed? Charles Anderson, a Maldives-based biologist, has 14 years of dragonfly data and an intriguing theory. The insects, which breed in pools of fresh water, appear to follow seasonal rains. Each fall this takes them from India to East Africa via the Maldives and brings them back on a similar route months later---a round-trip distance of some 11,000 miles. If Anderson is right, the globe skimmers' migration would be the longest of any insect, putting them in the company of other great travelers of the animal world. ---A. R. Williams MAJOR MIGRATIONS Like monarch butterflies, globe skimmer dragonflies are thought to complete a round-trip over the course of several generations. In other far-traveling species, individuals go the entire distance.