Other Environmental Themes

Come Fly With Me

Humans unravel the mysteries of migration, in large measure, by watching what animals do; observation has always lied at the heart of animal behavior studies. Efforts to save whooping cranes, the most endangered of the world's 15 crane subspecies, offer a rare instance of animals learning about migration by watching what human do. Starting in 2001, humans flying ultralight aircraft have led whooping crane chicks on their first migratory flight south from a wildlife refuge in Wisconsin to a newly-created wintering habitat in a Florida preserve—a 1,200-mile journey.

The goal of this undertaking—headed by Operation Migration, a Canadian organization, working in concert with an international advisory group called the Whooping Crane Recovery Team—is to revive an imperiled subspecies whose population 60 years ago had dwindled to just 15 individuals. Today, only one naturally-occurring migrating population of whooping cranes has survived—a flock that travels between Texas and northern Canada. Since an entire population could be wiped out by disease, hurricane, or human disturbance, ecologists believe that additional populations are needed to ensure whooping crane survival, which is the motivation behind establishing the Wisconsin-to-Florida flock.

As young cranes normally learn migration routes from their parents, the incubator-raised birds in Wisconsin needed someone, or something, to guide them. Disguised aircraft, piloted by humans, served as surrogate parents—the premise being that birds need only be shown the way once. The strategy has paid off: Since the program was initiated in 2001, three dozen cranes have made the roundtrip flight on their own. Whereas the ultralight-led trip to Florida may take up to two months, the return trip without humans is much faster: The five whooping cranes making the first unassisted migration reached Wisconsin in just 10 days. Thirteen more healthy, juvenile Whooping cranes were led south on a 64 day migration in December of 2004.

Although the results so far have been encouraging, it could take another decade before a stable breeding population of migrating whooping cranes—with 25 breeding pairs out of 125 birds in all—is in place.

Meanwhile, a similar approach is being used to protect endangered Siberian cranes, which are learning their migration routes—3,000-plus-mile journeys between Siberia and China, India, or Iran—with the help of airborne humans.