By Rebecca Morelle
Science reporter, BBC World Service
The mystery of the "Bermuda Triangle" of the homing pigeon world may have been solved.
For years, scientists have been baffled as to why the usually excellent navigators get lost when released from a particular site in New York State.
But new research suggests the birds are using low frequency sounds to find their way around - and they cannot hear the rumble at this US location.
The study is published in the Journal of Experimental Biology.
The lead author of the paper, Dr Jonathan Hagstrum, from the US Geological Survey, said that the birds were creating "acoustic maps" of their surroundings.
But some other researchers said the theory was controversial and there was much debate over how homing pigeons navigate so efficiently.