Homing pigeons and their posse
We have all heard how homing pigeons were used throughout history to send and receive messages because of their uncanny ability for navigation. They were used by the Greeks, Genghis Khan and some of them have even been awarded medals after World War I for their crucial delivery of messages on the war front.
But recent scientific research has proven that these avian navigational skills are much more complex and even mimic human dynamics of leadership and compromise when it comes to locating places.
Earlier avian orientation studies have already shown that pigeons have route memories developed from consecutive flights and that once enough experience is gathered, these memorised routes can guide birds back along this fixed flight path. While pigeons often fly with their posse, a group of scientists from the University of Oxford and University College London wondered if one homing pigeons’ memorised route influences the routes of another when they fly in pairs and in quadruples.
To test this, the researchers trained 16 adult homing pigeons (Columba livia) from the Oxford University Field Station. These birds had homing experience but had not yet navigated the sites used for the research. The pigeons were fitted with miniature GPS logging devices at their backs using small Velcro strips that were glued to their feathers. Forming eight pairs, they were released at Church Hanborough and College Farm, and trained to home in as individuals, then by pairs and then in quadruples until all possible combinations were performed.
The study found that pair pigeons do indeed develop peculiar routes together over consecutive homing flights. The paired pigeons will use an intermediate route if ever there is a need to compromise, and then separate only when a threshold distance is reached. What’s more interesting, the scientists found that the pigeons’ navigational learning mechanisms are similar whether developed solo or in pairs.
Furthermore, the peculiar routes developed with their pair pigeons were maintained when they flew in quadruples, with pigeons staying closer to their partners than the unfamiliar birds. But how do these birds resolve navigational differences when flying in fours? Pairs carry their stable routes to their small flock, so ultimately the direction of the quadruple is determined by a pair emerging as leader. Scientists also found that pigeon pairs who prefer routes based on landmarks emerge as the quadruple’s leader and followed on their way home.