How do birds navigate while migrating and how do homing pigeons navigate?
Magnetic hypothesis[]
Some research has been performed with the intention of discovering how birds can find their way back from distant places they have never visited before. Some researchers believe that pigeons navigate by Earth's magnetic field. Near their home lofts, in areas they have previously visited, pigeons probably are guided by natural and artificial landmarks.
Olfactory hypothesis[]
Research by Floriano Papi (Italy, early 1970s) and newer research published in the February, 2004 issue of Animal Behaviour suggest that pigeons also orient themselves by odors and/or combinations of odors. (See the August 20, 2005 issue of Science News.)
Various experiments suggest that different breeds of homing pigeons rely on different cues to different extents. Charles Walcott at Cornell was able to demonstrate that one strain of pigeons was confused by a magnetic anomaly in the Earth that had no effect on another strain of birds. 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 [1].