During the fall of 2009, three tiny Alaskan songbirds took an amazing three-month journey that began on a windswept dome northeast of Fairbanks and ended amid the arid grasslands of the southern Sudan in Africa — a 9,000-mile trip that traversed mountain ranges and deserts, including the Arabian Peninsula.
 
Then, once their winter sojourn in the Old World ended, the 25-gram birds — chirpy Northern wheatears that each weighed about as much as a couple of moose nuggets — flew back across the Asian landmass. 

Destination? Another summer of insect-scarfing bliss amid the New World tundra at Eagle Summit.
 
This 18,000-mile round-trip migration between sub-Arctic Alaska and sub-Saharan Africa might make these striking passerines the world’s champion avian sightseers, according to a new tracking study published this week in the journal Biology Letters.

The findings, made possible by ultra-lightweight tracking devices, also offered stunning new insight into migratory abilities of songbirds like the wheatear, whose wintering grounds were previously unknown but thought to be somewhere in the Eastern Hemisphere. 

“Our results provide the first incontrovertible evidence that a migratory songbird regularly travels between Arctic regions of the Western Hemisphere and Africa,” wrote the study’s eight German and Canadian authors in the conclusion of “Cross-hemisphere migration of a 25 g songbird.”

“Scaled for body size, this is the one of the longest round-trip migratory journeys of any bird in the world and raises questions about how a bird of this size is able to successfully undertake such physically demanding journeys twice each year, particularly for inexperienced juveniles migrating on their own.”

The same team of scientists also tracked a covey of wheatears from a separate population on Baffin Island in the high Canadian Arctic and found a similar epic trip that led to a different winter destination in western Africa. The single bird that returned with retrievable data had flown more than 2,100 miles over the Atlantic Ocean en route, a crossing that took four days of nonstop travel.

Incredible journeys for a bird the weight of a candy bar

“They are incredible migratory journeys, particularly for a bird this size,” said biologist Ryan Norris, a co-author of the study and a professor of integrative biology at the University of Guelph in Ontario, in this story. “Think of something smaller than a robin but a little larger than a finch raising young in the Arctic tundra and then a few months later foraging for food in Africa for the winter.

“This is the only known terrestrial bird that physically links the two radically different ecosystems of the Old World and the Arctic regions of the New World,” Norris added.

Details about the songbird's migration remained largely unknown because devices that could track  movements were too bulky, explained a story about the research. But “new smaller devices now allow scientists to track flights over several months and over long distances."

The gizmos — called “geo-locators” — weighed only about 1.2 grams or about 1/25^th of an ounce. They attach to the birds with a harness that loop the legs and don’t substantially interfere with the animal’s ability to fly or forage for food. (An equivalent device carried by a 180-pound scientist might weigh as much as a laptop computer, a bottle of water and a tuna sandwich, about eight pounds.)