National Geographic News
Homing pigeons are released at a festival in Caldwell, Idaho.

Homing pigeons take to the air to mark the start of Idaho's annual Festival of Flight.

Photograph by Greg Kreller, Idaho Press-Tribune/AP

Jane J. Lee

National Geographic News

Published January 30, 2013

Homing pigeons (Columba livia) have been prized for their navigational abilities for thousands of years. They've served as messengers during war, as a means of long-distance communication, and as prized athletes in international races.

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 the U.S. Geological Survey in Menlo Park, California.

"They're using sound to image the terrain [surrounding] their loft," he said. "It's like us visually recognizing our house using our eyes."

Homeward Bound?

For years, scientists have struggled to explain carrier pigeons' directional challenges in certain areas, known as release-site biases.

This "map" issue, or a pigeon's ability to tell where it is in relation to where it wants to go, is different from the bird's compass system, which tells it which direction it's headed in. (Learn about how other animals navigate.)

"We know a lot about pigeon compass systems, but what has been controversial, even to this day, has been their map [system]," said Cordula Mora, an animal behavior researcher at Bowling Green State University in Ohio who was not involved in the study.

Until now, the two main theories say that pigeons rely either on their sense of smell to find their way home or that they follow the Earth's magnetic field lines, she said.

If something screwed up their sense of smell or their ability to follow those fields, the thinking has been, that could explain why pigeons got lost in certain areas.

But neither explanation made sense to Hagstrum, a geologist who grew interested in pigeons after attending an undergraduate lecture by Cornell biologist William Keeton. Keeton, who studied homing pigeons' navigation abilities, described some release-site biases in his pigeons and Hagstrum was hooked.

"I was just stunned and amazed and fascinated," said Hagstrum. "I understand we don't get dark matter or quantum mechanics, but bird [navigation]?"

So Hagstrum decided to look at Keeton's pigeon release data from three sites in upstate New York. At Castor Hill and Jersey Hill, the birds would repeatedly fly in the wrong direction or head off randomly when trying to return to their loft at Cornell University, even though they had no problems at other locations. At a third site near the town of Weedsport, young pigeons would head off in a different direction from older birds.

There were also certain days when the Cornell pigeons could find their way back home from these areas without any problems.

At the same time, homing pigeons from other lofts released at Castor Hill, Jersey Hill, and near Weedsport, would fly home just fine.

Sound Shadows

Hagstrum knew that homing pigeons could hear sounds as low as 0.05 hertz, low enough to pick up infrasounds that were down around 0.1 or 0.2 hertz. So he decided to map out what these low-frequency sound waves would have looked like on an average day, and on the days when the pigeons could home correctly from Jersey Hill.

He found that due to atmospheric conditions and local terrain, Jersey Hill normally sits in a sound shadow in relation to the Cornell loft. Little to none of the infrasounds from the area around the loft reached Jersey Hill except on one day when changing wind patterns and temperature inversions permitted.

That happened to match a day when the Cornell pigeons had no problem returning home.

"I could see how the topography was affecting the sound and how the weather was affecting the sound [transmission]," Hagstrum said. "It started to explain all these mysteries."

The terrain between the loft and Jersey Hill, combined with normal atmospheric conditions, bounced infrasounds up and over these areas.

Some infrasound would still reach Castor Hill, but due to nearby hills and valleys, the sound waves approached from the west and southwest, even though the Cornell loft is situated south-southwest of Castor Hill.

Records show that younger, inexperienced pigeons released at Castor Hill would sometimes fly west while older birds headed southwest, presumably following infrasounds from their loft.

Hagstrum's model found that infrasound normally arrived at the Weedsport site from the south. But one day of abnormal weather conditions, combined with a local river valley, resulted in infrasound that arrived at Weedsport from the Cornell loft from the southeast.

Multiple Maps

"What [Hagstrum] has found for those areas are a possible explanation for the [pigeon] behavior at these sites," said Bowling Green State's Mora. But she cautions against extrapolating these results to all homing pigeons.

Some of Mora's work supports the theory that homing pigeons use magnetic field lines to find their way home.

What homing pigeons are using as their map probably depends on where they're raised, she said. "In some places it may be infrasound, and in other places [a sense of smell] may be the way to go."

Hagstrum's next steps are to figure out how large an area the pigeons are listening to. He's also talking to the Navy and Air Force, who are interested in his work. "Right now we use GPS to navigate," he said. But if those satellites were compromised, "we'd be out of luck." Pigeons navigate from point to point without any problems, he said.

7 comments
Antonio  Nafarrate
Antonio Nafarrate

The Gyroscopes are the internal rotors in the molecule of ATPase. They spin at some 10000RPM. I have been studying this for the past 40 years. Check the website animalnav dot org.  They sense the rotation of the Earth similar to what a Foucault pendulum does by the Coriolis acceleration. If you launch a top spinning pointing to some Star after one hour the top will be pointing to a place 15 degrees East of that Star, The top remains vertical to the same place on the Earth, Bees do that in the hive while dancing because they "know" where the Sun is. I think that the Bees believe in Pre-Copernican Astronomy that the Earth is flat and the Center of the Universe (just like Joshua the Biblical character that stop the Sun, so their warriors could kill more of the others)


For aminadav, please check the website that I mentioned before you write something for the school.

Spartan King
Spartan King

MY YOUNG HOMING BIRD TOOK HER FIRST FLIGHT ALONE FOR FEW MINUTES AND RETURNED AND THE VERY NEXT DAY  SHE FLEW AWAY(31/5/2014)SOMEWHERE AND DIN RETURN STILL NOW WILL IT BE HOMED.../

aminadav berenstein
aminadav berenstein

Very interesting!

I am writing something about this matter to be used in schools,

 and  this article contains very important information. 

   Thanks   

      Aminadav   



Vince Caprice
Vince Caprice

As a racing pigeon enthusiast in the 1940's I remember a study made that indicated that the only notable difference found internally between a street pigeon and a homer was a small cavity in the head that was not in the street pigeon's skull.  

When we started racing, most birds came home the same day in the 600 mile race.  On June 8,1946, we had the only, and I think the last day bird in Philadelphia in that race until we quit in 1949. Second place came in the following morning.  The pros blamed the loss in flying time on the new electronic (radar, etc) devices fostered in WWII.

In the research, I read nothing about the cavity or the electronics.  Have these theories been abandoned?

Vince Caprice
Vince Caprice

As a racing pigeon enthusiast in the 1940's I remember a study made that indicated that the only notable difference found internally between a street pigeon and a homer was a small cavity in the head that was not in the street pigeon's skull.  

When we started racing, most birds came home the same day in the 600 mile race.  On June 8,1946, we had the only, and I think the last day bird in Philadelphia in that race until we quit in 1949. Second place came in the following morning.  The pros blamed the loss in flying time on the new electronic (radar, etc) devices fostered in WWII.

In the research, I read nothing about the cavity or the electronics.  Have these theories been abandoned?

Papa Foote
Papa Foote

Many, Explore - That's GOOD, from The Old Mountain Goat!

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