The joy of discovery is what captivates many people with the natural world. Bird enthusiasts, in particular, revel in the search for bird species not seen before in the backyard, the state, and even the country. We especially enjoy finding birds we have never seen before, anywhere. The search for those birds a person has never seen before—“lifers” as they are called by birders—can be all consuming for some who travel the ends of the earth to find as many of them as they can.

The backyard feeder watcher who may or may not travel far away to look for new birds may be just as excited to find a new bird species coming to the feeder, especially if it is a “lifer.” Sometimes the discovery is not a new bird but a behavior that the observer has never seen before.

Ornithologists, too, love to make a new discovery, especially one that no one had predicted. Just such a discovery was published and made the news a few weeks ago. Researchers at Lund University in Sweden placed one gram backpacks onto common swifts—an ever-so-slightly larger version of our summer resident chimney swift. Those backpacks contained two things. One was a light-sensitive geolocator that, when retrieved, can show where the birds traveled across the Earth. The other was what is called an accelerometer, a device that keeps track of the bird’s wingbeats and forward motion.

Common swifts breed across Europe and Asia and, like our chimney swift, have now almost completely adapted to nesting on human structures. Unlike chimney swifts that nest mostly in chimneys as the name suggests, common swifts will nest under eaves and in various nooks and crannies of tall, old buildings. Just like our chimney swifts and all swifts worldwide, common swifts are completely dependent on aerial insects for food. Their feet and legs are tiny and situated far back on the body. They have great difficulty maneuvering on a flat surface but are fine for hanging on to a vertical surface like a wall, chimney, or the inside of a large, hollow tree.

After the Lund University researchers affixed the backpacks to a group of common swifts during the summer breeding season, the swifts disappeared as they migrated south to the tropics. The following breeding season, the researchers captured the birds and removed the backpacks. They downloaded the data to see what the birds had been up to over the past year. They found that the birds from Sweden had spent the winter over the forests of the Congo Basin.

That was interesting enough.

But there was an even more astonishing discovery to come:  some of the birds had never stopped for an entire period of 10 months!  This is the longest nonstop bird flight ever documented. Even those swifts that had stopped had only done so for a few hours at irregular intervals.

There is more work to be done to understand how this is possible, but the researchers surmise that at dusk the birds fly to very high altitudes and then do a long, slow glide to lower altitudes that may allow them to nap on the wing.

Talk about multitasking!

Jeffrey V. Wells, Ph.D., is a Fellow of the Cornell Lab of Ornithology. Dr. Wells is one of the nation's leading bird experts and conservation biologists and author of the “Birder’s Conservation Handbook.” His grandfather, the late John Chase, was a columnist for the Boothbay Register for many years. Allison Childs Wells, formerly of the Cornell Lab of Ornithology, is a senior director at the Natural Resources Council of Maine, a nonprofit membership organization working statewide to protect the nature of Maine. Both are widely published natural history writers and are the authors of the book, “Maine’s Favorite Birds.”