Even birds get jet lag: fast flights skew seabirds' Sun compass, Oxford study finds

Anyone who has stepped off a long flight knows the feeling. Your body says it is night while the Sun says it is noon. Do birds get jet lag too? A new study says yes, and for one seabird it shows up somewhere you might not expect: in the direction it flies.

Researchers at the University of Oxford looked at GPS tracks from 1,045 wild Manx shearwaters racing home across the sea. When the birds flew fast to the east or west, their inner clock fell out of step with local Sun time. Their sense of direction then drifted in a way the team could predict. The paper, led by Patrick Lewin with Tim Guilford among 24 authors, was published in Science on 29 October 2026.

Do birds get jet lag? Ask a seabird that steers by the Sun

The Manx shearwater is a seabird common around the British Isles and a close relative of the albatross. A pair raises a single egg. One partner sits on it while the other hunts fish and squid at sea for up to two weeks, NPR reports. The trip home, often more than 1,000 km from feeding grounds in the Northeast Atlantic to colonies in the UK, can take about a day.

To steer by the Sun, a bird has to know the time. “To use the sun as a compass you have to know what time of day it is,” Lewin, a behavioural ecologist at Oxford, told NPR. The Sun crosses about 15 degrees of sky every hour. So a clock that is off by even part of an hour points the bird a little the wrong way.

That is the sun compass, and an Oxford-led team including Guilford showed in 2018, by shifting the clocks of nesting birds, that shearwaters use it.

How fast flights east and west bend the bird’s heading

This time nobody touched the birds’ clocks. The flights did it. Crossing longitude quickly changes local Sun time faster than the body clock can follow. The team expected eastward flights to pull the heading clockwise and westward flights anticlockwise, and the tracks matched.

The researchers also checked the obvious rival: Earth’s magnetic field, which birds can sense too. The errors fit a Sun-compass mistake better than a magnetic one, according to the AAAS release. More surprising, the birds kept using the Sun even while following a coastline, when the land itself could have guided them.

The open question is how far jet lag reaches

The effect is small. “It’s a really small addition,” Lewin told NPR. Reports of exactly how big the drift is vary, so we have left a figure out until it can be checked against the paper’s own numbers.

The bigger question is what else shifts. The authors write that fast east-west travel “may affect other processes governed by the endogenous clock”, the body’s built-in daily timer. Alice Boyle, a biologist at Western University in Canada who was not part of the study, told NPR: “This paper is so cool.”

How do birds navigate? A lesson for every traveller

For anyone who flies, this is a reminder that jet lag is not a human quirk. Do animals get jet lag? This study suggests the body clock most living things share can trip up a wild bird as well. Other animals known to steer by the Sun, such as honeybees and monarch butterflies, are natural places to look next.

For conservation, it is useful to know which limits are built in. Wild-animal science like the recent study on wind turbines and bats depends on knowing how animals move. Clock-driven errors are one more piece of that picture.

Why a small error tells a big story about body clocks

On balance, this is careful, patient science. About 20 years of tracking (according to NPR), a clear prediction and a check against the magnetic explanation make the result convincing. Its value is less about lost birds, who still get home, and more about a new way to study body clocks in the wild.

The honest limit is that this is one species on one kind of journey. Whether long-distance migrants show the same drift is still unknown. Our reading is that the study is a meaningful step, not the last word.

Humans are busy debating clocks too, with world timekeepers voting to stop adding leap seconds. The shearwaters remind us that the oldest clock is the one inside us. Next, watch for the same test on migrating birds that cross whole time zones.