How Do Homing Pigeons Find Home?
Homing pigeons seem to have a compass built right into their heads. They can be taken hundreds of miles from their homes. When they are let go to fly again, they find their way home.
Scientists don’t know exactly how the pigeon’s “compass” works, but they have found tiny pieces of a special kind of iron, called magnetite, in homing pigeons’ heads.
These little pieces are natural magnets, and could enable the pigeon to sense direction from the Earth’s magnetic field. Homing pigeons can also tell direction accurately from the sun’s position.
Various experiments suggest that different breeds of homing pigeons rely on different cues to different extents.
Charles Walcott at Cornell University was able to demonstrate that while pigeons from one loft were confused by a magnetic anomaly in the Earth it had no effect on birds from another loft 1.6 km (1 mile) away.
Other experiments have shown that altering the perceived time of day with artificial lighting or using air conditioning to eliminate odors in the pigeons’ home roost affected the pigeons’ ability to return home.
Some research also indicates that homing pigeons navigate by following roads and other man-made features, making 90 degree turns and following habitual routes, much the same way that humans navigate.
Recent research by Jon Hagstrum of the US Geological Survey suggests that homing pigeons use low frequency infrasound to navigate.