Posted by Allan_Lang on February 05, 2004 at 04:34:19 from 202.61.171.25 user Allan_Lang.
They follow roads
By Caroline Davies
(Filed: 05/02/2004)
Researchers have cracked the puzzle of how pigeons find their way home: they just follow the main roads.
"It really has knocked our research team sideways to find that after a decade-long international study, pigeons appear to ignore their inbuilt directional instincts and follow the road system," said Prof Tim Guilford, reader in animal behaviour at Oxford University's Department of Zoology.
"For long-distance navigation and for birds doing a journey for the first time, they will use their inbuilt compasses and take sun and star bearings.
"But once homing pigeons have flown a journey more than once, they home in on a habitual route home, much as we do when we are driving or walking home from work.
"In short, it looks like it is mentally easier for a bird to fly down a road and then turn right. They are just making their journey as simple as possible".
His team carried out dozens of tests with pigeons in Oxfordshire, releasing them between 10 and 20 miles from their lofts, each with a tiny GPS tracking device attached to their backs. Matching their routes, they found most flew straight down the A34 Oxford bypass.
"It was almost comical watching one group of birds that we released near a major A road. They followed the road to the first junction where they all turned right, and a couple of junctions on, they all turned left".
Not all of the pigeons did it all of the time, but there were enough occasions when they did for the researchers to build up a pattern.
"We even had one bird flying down the road, going round the roundabout, taking one of the turnings down that to another roundabout then leaving the road.
"Up until now, we have always thought about the way that birds go in terms of the energetics of the flight efficiency, which is the most direct route home . . . as in the phrase 'as the crow flies'.