But there are places around the world that seem to confuse these birds—areas where they repeatedly vanish in the wrong direction or scatter on random headings rather than fly straight home, said Jon Hagstrum, a geophysicist who authored a study that may help researchers understand how homing pigeons navigate.

Hagstrum's paper, published online Wednesday in the Journal of Experimental Biology, proposes an intriguing theory for homing pigeon disorientation—that the birds are following ultralow frequency sounds back towards their lofts and that disruptions in their ability to "hear" home is what screws them up.

Called infrasound, these sound waves propagate at frequencies well below the range audible to people, but pigeons can pick them up, said Hagstrum, who works at