Navigation: How Birds Find Their Way When They Migrate

Migration Basics | Navigation | Flyways | Evolution of Migration

Updated May 2026; first published April 2008.

Twice a year billions of birds take to the skies as they migrate to and from their summer and winter homes (or breeding and nonbreeding grounds).

And every year birders delight in seeing these old friends return after navigating untold challenges and hundreds or even thousands of miles along the way. But how do the birds manage to find the places they call home? Even young birds that have never migrated before somehow know where to go—and many of them make that first migration without their parents showing them the way. How?

Ornithologists have been captivated by migration for more than a century. In that time, they’ve honed theories and uncovered many of the abilities that let birds accomplish such remarkable feats of orientation and navigation.

To get from point A to B, birds rely on two related abilities: orientation and navigation. Migrating birds need a compass to guide them in the right direction—that’s orientation. And they need some kind of internal map to know where they are and where they are going—that’s navigation. Let’s take a look at each of these in turn:

Orientation: How Birds Know Which Way to Go

To head in the right direction, migrating birds use some of the same cues that ancient mariners used, like the sun and stars. And they also have senses that we don’t possess. 

The sun compass

People use the position of the sun to tell the time, to gauge the cardinal directions, and—for sailors at least—to plot their latitude and longitude. Similarly, birds can use the sun’s position to help them orient.  

For example, a researcher in the 1950s studied how captive European Starlings use the sun to orient. He used mirrors to experimentally shift the sun’s apparent location. In response, the birds oriented themselves and attempted to fly in the “wrong” direction indicated by the new position of the sun. This experiment suggests that the position of the sun in the sky helped the starlings know which way to go.  

Additional research has shown that the bird’s sun compass is tied to its circadian rhythm, or internal clock. Shifting the number of hours captive birds were exposed to light simulated a different season of the year, and this caused them to fly in the opposite direction relative to the sun’s position.  

The sun’s position can also help birds orient themselves for daily movements. Researchers have found that jays and nutcrackers use the sun’s position to relocate nuts and seeds they’ve cached.  

Polarized Light 

Patterns of polarized light also appear to play a role in orientation. When light reflects off the Earth’s surface, it becomes polarized: all (or most of) the light rays are oriented in the same direction. Birds can sense this directionality and use it to orient themselves. Light polarization also occurs during sunrise and sunset, when many nocturnal migrants begin or end their flights. Photoreceptors in a bird’s eye can help them use patterns of polarized light to help with initial migratory flight directions. 

The Star Compass

Sunlight plays a role in orientation during the day, but many songbird species migrate at night. What do they do? They use the stars. 

Up until the 1960s, scientists thought birds had an innate knowledge of the stars that they used like a map. This theory was refined in 1967, when Cornell scientist Stephen Emlen proved that birds don’t learn star maps, exactly. Rather they notice the rotation of the stars and use that to determine a north-south orientation—a particularly useful cue for long-distance migrants at night.  

Magnetic Cues for Orientation and

For centuries people have used compasses to orient themselves in relation to the magnetic field of the Earth. Birds can sense this field innately, and their senses allow them to determine more than just their north-south orientation.

Compasses work by allowing a magnetized needle to align with the Earth’s magnetic field, which runs roughly north-south. Birds have a magnetic mineral in their bills that allows them to sense these directions. It may also allow them to perceive small changes in the Earth’s magnetic field, which becomes slightly stronger as you move away from the equator and toward the poles. By sensing these small changes combined with magnetic declination (direction relative to true north) and inclination (angle of the Earth’s magnetic field), they may be able to determine not just their orientation, but also their position on the planet.

Birds may also use their eyes to detect the direction of the Earth’s magnetic field. Experiments have found that blue and turquoise light interact with components in the bird’s retina that may allows birds to “see” where to go; a sense that researchers have likened to a magnetic map. 

Navigation: How Birds Know Their Route 

Landmarks 

Birds that migrate during the day often follow natural landforms such as mountain ranges, rivers, and lakes. 

Raptors migrating through the eastern U.S. may follow the Appalachian Mountains or the eastern coastline—as evidenced by long-running hawkwatch sites including Hawk Mountain, Pennsylvania, and Cape May, New Jersey.

Some waterfowl follow the Mississippi River through the Midwest. The massive river valley provides them with a clear north/south direction. Over time, birds may learn additional landmarks that they incorporate into their wayfinding. Young Cory’s Shearwaters, for example, take longer to arrive at their nonbreeding sites because they take more time to explore the route, helping them figure out the best route in subsequent years. 

Sense of Smell

It’s often suggested that birds have a poor sense of smell, but there’s a growing realization that this is not true, and that many birds have excellent olfactory abilities. And some birds even use smell to guide them to where they need to go.

Many seabirds have very keen sense of smell, particularly the tubenoses (shearwaters, storm-petrels, petrels, and albatrosses). They use smell to home in on food in the open ocean and to find their way back to their breeding colony after spending a year away at sea. 

Other birds can also use their sense of smell to determine their location, and homing pigeons (domesticated Rock Pigeons) are a good example. Here’s a simplified scenario of how it might work:  

Visualize a pigeon in its home loft. The smell of pine trees comes from one direction while the smell of an onion farm comes from another. If the bird moves closer to the pine trees, the odor of pine will presumably grow stronger while the odor of onions grows weaker. In theory, a gradient map of odors could be created that would provide some directional information, even if the pigeon was suddenly dropped into a new location. 

Using Multiple Cues at Once

Migration takes a long time, covers vast parts of the globe, and happens in all kinds of weather. So it makes sense that birds can’t use a single source of information to navigate.

Birds may migrate in the day, at night, in cloudy weather, through or around storms, etc. Instead of relying on one main type of compass, birds likely use multiple methods and calibrate them against each other. Some species use one type of compass as the primary navigational aid while others rely on a different primary system. The complexity of migration and the skill with which it is accomplished is one of the many marvels that make birds so interesting to study.