Unlocking Migration's Secrets

Photograph by Joel Sartore
Barry Truit/ Nature Conservancy
Joel Sartore

Unlocking Migration's Secrets

For centuries the study of bird migration has been riddled with mystery and unanswered questions: Where do birds go in winter? How far do they fly? Can they navigate a hurricane? Scientists are tapping new technologies to find the answers, and transforming everything we know--or think we know--about birds.

By Scott Weidensaul/Photography by Joel Sartore
Published: March-April 2012

Last August a female whimbrel took off from the treeless tundra of Southampton Island, which guards the iceberg-choked entrance to Hudson Bay in the Canadian subarctic, and set a course southeast.

Long-limbed and gray-brown, she was the size of a small duck, bearing the field marks that make this shorebird instantly identifiable--dark stripes on the crown of her head, and a long, thin, drooping crescent of a bill. It gives the whimbrel its genus name: Numenius, Greek for "new moon."

Southampton had merely been a way station for her; some weeks earlier she had arrived there from her breeding grounds on the Mackenzie River delta in the Northwest Territories, some 1,500 miles and 52 hours of flying time to the northwest. Now her bill was stained purple from weeks of gorging on the autumn tundra's bounty--blueberries, crowberries, and cloudberries, all of which her body had converted to thick layers of fat, fuel for the incredible journey ahead.

Tapered wings pumping without pause or rest, she flew east across Hudson Bay, passing thereafter over the rugged Ungava Peninsula of northern Quebec, then above the trackless boreal forests and wild rivers of Labrador. After 1,500 miles of unbroken flight, averaging 43 miles per hour, she left land behind, flying out into the open ocean somewhere south of Newfoundland.

Connectivity Map
Illustration by Peter Hoey
High Hope: A Whimbrel's Migration

It was here that she ran into trouble. Her flight path brought her into the remnants of Tropical Storm Gert, which was roiling its way up the north Atlantic. Fighting ferocious headwinds, the bird struggled to stay aloft as she plowed ahead at a painful crawl; for the next 27 hours her average ground speed slowed to a mere nine miles an hour.

Finally she broke through to the storm's far side. Now, with the gale at last at her back, she rocketed along at 92 mph. In little more than 90 minutes she flew 150 miles to make landfall at Cape Cod--her first rest since she'd taken off from Southampton Island four days and 2,325 miles earlier.

That we know about this migratory drama at all, much less in such extraordinary detail, is thanks to a small satellite transmitter nestled among the feathers on the whimbrel's back--part of a transformation in wildlife tracking that is making it possible for scientists to understand the movements of migratory animals with a level of precision unimaginable even a few years ago. They can comb through the chemical isotopes in a bird's feather and learn where it spent the winter, sift the DNA in its genes to tease out how migratory populations are related to one another, attach minute devices that faithfully record its location for years at a stretch by just observing the time the sun rises and sets each day, or track threatened eagles in the Appalachians by tapping into the ubiquitous cell phone network (and thus help planners avoid conflicts with new wind farms). They have found that neighboring populations of the same species may take wildly different routes to far-flung wintering areas, and that many birds show an almost incomprehensible degree of fidelity to particular stopover and wintering sites.

With that new knowledge has come a recognition of what we've badly underestimated: the profound, almost universal role that migration plays in virtually every aspect of a wild bird's life--and, with it, a new effort by dozens of researchers, agencies, and organizations like Audubon to better map these movements, better understand their significance, and harness this greater understanding for the benefit of birds.

"This new generation of telemetry has enormous potential for understanding bird biology and conservation," says Steve Kress, Audubon's vice president for bird conservation, and the founder of Project Puffin. "The new data loggers and transmitters could be far more important than bird bands, and future ornithologists may someday think of placing metal rings on bird legs as being as primitive as we might think of John James Audubon's method of tying a silver thread to a phoebe leg. This is because these new devices give us the ability to track individual birds throughout the year--something that a band was never intended to do." (To learn about the migratory secrets of some other individual species, from long-tailed ducks to pink-footed shearwaters and golden eagles, go to audubonmagazine.org.)

But by lifting the veil that has masked much of where and when birds travel, conservationists not only realize how little they know about migration. They've also learned, sometimes to their grief, that they have badly underestimated, too, the dangers facing these global wanderers--birds like the whimbrel named Hope.


Magazine Category

Author Profile


Read all news about birds

Read all news about birds with application at feedervu.com. Just use it;-)

I am happy to find your

I am happy to find your distinguished way of writing the post. Now you make it easy for me to understand and implement the concept. Thank you for the post.

Further Information?

Excellent article. The truth of these birds' migratory patterns takes my breath away. How much we have to learn. And what a phenomenal tool in avian wildlife management. I, too, have been trying to find further information on the topic. Links? Also, are there any online sites for following real time transmissions from study birds?

transmitted birds

I'm not convinced that the data gained (beyond what has already gained anyhow) offsets the downside to transmitters. No one ever mentions the harnesses that hold the transmitter in place, which will stay on the bird forever, even if (as is usually the case) the transmitter falls off. If the bird is not full grown when the harness is fitted, it will end up being constricting to the point of pain and possibly causing a loss of range of motion. Cloth harnesses have torn and partially fallen off and caught on branches, sometimes with fatal results. Coating clothe with Teflon is more sturdy, but Teflon off-gasses chemicals. Any kind of harness can cause chafing, sometimes painful and debilitating. And i have yet to find anyone who will answer the question about batteries, which as they degrade, leach caustic, toxic fluid. Most are 'recharged' with solar packs, but the original batteries are still lithium and will leach battery acid.


A study was done in 1989 on spotted owls with transmitters attached to them. Of the 48 owls with transmitters, 37 died in the first year. I really don't think science is discovering new information from these, and the potential harm to the animal is very real. I just can't understand why people are so unsympathetic to this issue. Survival of all birds is so precarious to begin with, and this just makes it more difficult for it to be successful.

Hope, the Whimbrel

I used to wish I was a peregrine and now wish I was a whimbrel.
Why the pic of an imme peregrine?


I think it's amazing that a small bird can fly so far in such short amount of time. I think the author did a great job, with this article. Go Hope!

I am from Barbados, one of

I am from Barbados, one of the islands mentioned in this excellent article. It is a sad fact that there are artificial shooting swamps on Barbados where migratory shore birds are shot in their thousands. Concerned individuals including myself have been engaged in a campaign with the shooters to encourage conservation. We have had some limited success. Whimbrel are no longer shot except by one or two rogue shooters. The sanctuary to which reference was made is now open..Woodbourne Shorebird Reserve, which this year saw both whimbrel and red knot coming to feed and drink. I hope to live to see the day when no further shooting takes place, but the process of converting the shooters to conservationists is a long, arduous one. The good news is that we have made some progress.

Excellent article

This is one of the most fascinating articles on bird migration I've ever read!


May the Creator lf all protect these little marvels from all harm most of all us the human species. God bless them.

Add comment

The content of this field is kept private and will not be shown publicly.
By submitting this form, you accept the Mollom privacy policy.