How Migratory Birds Navigate Across Continents

Sun, stars, smell and the Earth’s magnetic field: birds combine several compasses to find their way.

By Biosphere Editorial Team · 2026-09-02

Every year billions of birds travel between breeding and wintering grounds. Some of these journeys are almost unbelievable in scale.

Bar-tailed godwits (Limosa lapponica) fly from Alaska to New Zealand without stopping to feed or rest; in 2022 a tagged juvenile covered more than 13,000 km in a single flight.

More than one compass

• The sun — birds can compensate for its movement across the sky using their internal clock.
• The stars — classic planetarium experiments with indigo buntings showed that young birds learn the centre of rotation of the night sky.
• The magnetic field — many birds can sense the Earth’s magnetic field. One leading hypothesis involves light-sensitive proteins called cryptochromes in the eye.
• Smell and landmarks — some seabirds appear to use odours, and many birds follow coastlines, rivers and mountain ranges.

Why it matters for conservation

Migratory birds depend on a chain of habitats, from Arctic breeding grounds to coastal stopover sites. Losing a single link can affect an entire flyway. Artificial light at night can also disorient birds that migrate in the dark, which is why many cities run “lights out” campaigns during migration season.