Imagine spending nearly an entire year in the air—no rest stops, no landing, just endless movement through the sky.
It sounds like something out of a science fiction novel, but for the common swift (Apus apus), it’s just business as usual.
Thanks to groundbreaking technology, scientists have now confirmed what was once only suspected: these birds can remain airborne for 10 months straight without ever touching the ground—a record-breaking feat in the natural world.
This discovery not only redefines our understanding of avian endurance but also pushes the limits of what we thought possible for any flying species.
Just how do they achieve this seemingly impossible task? And what does it tell us about the secret lives of birds?
Let’s dive into the science behind one of nature’s most awe-inspiring travelers.
The Discovery That Changed Everything
For years, ornithologists speculated that swifts spent an extraordinary amount of time in the air, but proving it was another matter.
That changed when a team of researchers from Lund University in Sweden fitted 13 common swifts with miniature electronic tags—tiny backpacks weighing less than a gram.
Over two years, these devices meticulously tracked the birds’ movements, recording whether they were airborne or grounded, as well as their speed, acceleration, and location.
The results? Three of the birds never landed for 10 months.
Even those that did touch down stayed airborne for an astonishing 99.5% of their migration period—a statistic that shatters previous flight records.
Before this discovery, the alpine swift held the title for longest sustained flight, managing six months in the air.
The common swift has nearly doubled that record.
“This discovery significantly pushes the boundaries for what we know about animal physiology,” says Anders Hedenström, one of the researchers behind the study.
“A 10-month flight phase is the longest we know of any bird species—it’s a record.”
How Do They Do It? The Secrets of Endless Flight
Surviving for nearly a year in constant motion presents some mind-boggling challenges.
How do swifts find food, avoid exhaustion, and—perhaps most mysteriously—how do they sleep?
1. Eating on the Fly
Common swifts are aerial insectivores, meaning they catch and eat insects mid-flight.
Their highly efficient hunting techniques allow them to feed while moving, much like a shark constantly swimming through the ocean.
Researchers estimate that a single swift can consume up to 20,000 insects a day, ensuring they have enough energy to fuel their perpetual journey.
2. Sleeping While Soaring?
One of the biggest questions is whether these birds sleep at all during their epic flights.
Some scientists speculate that swifts engage in unihemispheric slow-wave sleep (USWS)—a phenomenon seen in some marine mammals and birds like the frigate bird.
This means they could be partially awake and partially asleep at the same time, allowing them to maintain flight while resting their brains.
Another clue lies in their behavior: every dawn and dusk, swifts ascend to altitudes of 2–3 kilometers (6,500–10,000 feet). Researchers believe this may be the period where they enter brief gliding phases, possibly allowing for short bursts of sleep while descending.
The Swifts’ High-Stakes Migration
The annual migration of common swifts is nothing short of spectacular.
These birds travel from Europe to Africa and back, covering hundreds of thousands—if not millions—of miles over their lifetimes.
On average, a swift lives 5.5 years, meaning some individuals may rack up a flight distance equivalent to traveling to the Moon and back multiple times.
Interestingly, the study also revealed that only the continuously airborne birds molted their feathers mid-flight, whereas the ones that landed did not.
This suggests that swifts have evolved to self-maintain their feathers while flying, further reinforcing their ability to survive without landing.
Breaking the Common Assumption About Birds and Rest
Most of us assume that all birds, no matter how skilled in the air, must land regularly to rest.
After all, even the most powerful migratory species like the Arctic tern—a bird that flies from the Arctic to the Antarctic each year—must stop to eat and regain strength.
But swifts challenge that assumption entirely.
Unlike any other known bird, they have seemingly adapted to a life of permanent flight, proving that landing is not an essential requirement for survival.
In essence, their version of “rest” happens while still in motion—a feat that no land animal can even come close to replicating.
What This Means for Science and Conservation
Understanding how swifts manage their near-perpetual flight has massive implications for multiple fields:
Animal Physiology: How do they avoid muscle fatigue? Do they require less oxygen over time? These are questions researchers are eager to explore.
Sleep Science: Could studying swifts unlock new insights into how sleep works? If they truly sleep while gliding, this could offer clues into how other species—possibly even humans—could optimize rest under extreme conditions.
Conservation Efforts: Swifts are facing a decline due to habitat loss and climate change. Knowing their migratory patterns in detail can help inform conservation strategies to protect critical feeding and breeding areas.
A Glimpse Into a Different Kind of Existence
The common swift’s ability to fly continuously for 10 months shatters our understanding of what birds—and living creatures in general—are capable of.
While humans have long dreamt of permanent flight, nature has already achieved it with breathtaking efficiency.
As scientists continue to unravel the mysteries of these sky-bound marvels, one thing remains certain: the swift is a living testament to evolution’s extraordinary ingenuity.
In a world where the sky is the limit, swifts have turned it into their entire existence.
So the next time you see a bird soaring above, remember—some of them may not touch the ground for nearly a year. And that’s a record worth celebrating.
What do you think about the swift’s record-breaking feat? Drop a comment below!
