Overview
- Researchers at the University of Oxford published a paper in Science on Monday that used 20 years of GPS tracking from 3,688 Atlantic storm‑petrel flights.
- Statistical analysis shows internal circadian clocks lagged by as much as about one hour and produced directional errors that reached roughly 15 degrees and averaged about 7 degrees.
- Those navigation errors appeared mainly on east–west flights, where a shifted internal clock causes predictable misreading of the sun used as a compass.
- The measured deviations added only modest extra distance—for example about five extra kilometres on a 1,000‑km trip—and birds seem able to reassess and correct course during flight.
- Authors say the effect is real but small and call for further study to test whether clock mismatch changes foraging success, energy use, or long‑term health.