What happens to a pigeon's eyes in flight is not what you would guess, and scientists have found it

Pigeon eyes during flight study: Most people assume that birds constantly move their eyes around while flying, scanning the world below as they navigate through the air. But a new study suggests pigeons do something surprisingly different once they leave the ground.

Researchers from Harvard University discovered that pigeons keep their eyes almost completely fixed during flight, holding them in a stable position rather than actively looking around, as per a report.

The findings, published in the journal Current Biology, reveal a behavior that scientists had long suspected but had never been able to test directly.

Scientists Finally Got a Pigeon's-Eye View

Studying a bird's eyes while it is flying is not easy. To solve the problem, researchers designed a lightweight system that allowed them to track the pigeons' eye movements in real time, as per a Phys Org report. The setup included a small headpiece fitted with a camera sensor, lens, and lightweight mirrors that monitored both pupils at once.


Each pigeon also carried a small backpack containing a battery to power the equipment. Nine pigeons participated in the study. Three completed outdoor homing flights of about 100 meters back to their coop, while six flew indoors through a 22-meter corridor under different visual conditions.

The Eyes Barely Moved at All

What researchers found was unexpected. While flying, the pigeons' eyes remained almost completely fixed. Instead of shifting their gaze around, the birds actively maintained nearly the same eye position throughout flight.

The position was so consistent that it varied by only about one degree from one flight to another. Researchers described this as the birds "locking" their eyes into place, Phys Org report.

Even more surprising, this behavior remained the same regardless of the surroundings. Whether the pigeons flew outdoors through a natural environment or indoors with plain or striped walls, their eyes stayed in essentially the same position.

Their Pupils Changed Too

The researchers noticed another change once the birds became airborne. During flight, pupil size increased by nearly 70%.

A larger pupil allows more light to enter the eye, and the researchers suggest that this may help pigeons process rapidly changing visual information while moving through the air, Phys Org report.

Why Keeping the Eyes Stable May Help

The fixed eye position appears to align closely with the main horizontal axes of the pigeons' inner-ear balance system.

Researchers believe this alignment may help the birds combine visual information with balance information more effectively during flight, Phys Org report. By keeping their eyes in a stable position, pigeons may be better able to perceive their own movement and maintain control while navigating through the air.

A Flight Behavior Hidden in Plain Sight

On the ground, pigeons rely on head movements and small eye adjustments to look around, much like many other animals.

But once they take flight, their visual strategy changes dramatically. Instead of constantly scanning with their eyes, they appear to lock their gaze into a nearly fixed position, creating a stable view that may help them stay oriented and on course.

FAQs

What did scientists discover about pigeons' eyes during flight?
They found that pigeons keep their eyes almost fixed in one position while flying.

Do pigeons move their eyes around in the air?
Very little. Their eyes remain locked in a near-consistent position throughout flight.