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Jon Explaining a Chart of Pigeon Vanishing Bearings

The earth is ringing; an ultra-low frequency bell. The reverberation of ocean water in motion is the most consistent clapper, although there are many other sources. Jon Hagstrum has shown that these ultra long sound waves, (infrasound) modulated by atmospheric conditions and topography, create the sonic map used by pigeons (and perhaps many other animals) to navigate.

A few weeks ago I met Doug and Beth for dinner and an evening listening to Jon present a updated summary of findings in his 30 year long quest to understand avian navigation

The research has moved to a new level with Jon's discovery and updating of HARPA, a powerful, if somewhat antique program written by Mike Jones in the 1980s (in FORTRAN !) that allows the user to enter atmospheric information like wind speed, temperature, barometric pressure, altitude and topography and to then model the propagation of acoustic waves –including infrasound. After much work to enable the program to run more reliably on today’s computers, Jon is able to input atmospheric and geophysical data from specific days and locations, model infrasound propagation under those conditions and to then search for correlations with changes in the homing behavior of pigeons.

Speed Of Sound by Temperature and Elevation

(Including angles of reflection from various surface sources angels)

What I find striking in hearing Jon’s research is not only his key finding of the role of infra sound as the map pigeons use in navigation, but also the building process of science in which one advance is made possible only by many others. The work of Mike Jones provides an essential tool, but more important is the work of William Keeton, a great biology professor, researcher and member of the Neurobiology and Behavior Department at Cornell, whose research and passion for the subject provided the spark and much of the data to make Jon’s work possible.

As an undergraduate at Cornell in the 1970s, Jon heard a lecture by Dr. Keeton .

William Keeton & friend

Having kept homing pigeons as a boy, Keeton was a pioneer in avian navigation studies and he founded a research pigeon loft. At its peak over 2000 pigeons were kept at the Cornell loft. Students and researchers compiled detailed data on the homing behavior of pigeons released in the area. Many experiments were conducted on the variables that seemed to influence the ability to home. My personal favorite: pigeons released with small bar magnets attached to their bodies to test the role of magnetic fields in navigation. (Result – the bird’s ability to orient quickly was affected, but not their ability to home.) Keeton’s research revealed that there are multiple cues used by homing pigeons and that when one failed, another was used. For example, the sun clearly played a role in orientation, but trained pigeons could orient and home quite well on overcast days too. And adding to the mystery of avian navigation and the value of Keeton’s data was the presence of two locations in the research area where homing ability was predictably disrupted. What was going on? He spent his life as a researcher trying to tease out the mechanism for pigeon homing. From the efforts of Keeton, his colleagues and students, much was learned and a huge data base was amassed documenting pigeon homing behavior on an almost daily basis over many years in the Cornell area. But key problems remained unsolved.

Essentially the ability of the birds to use a variety of cues as a compass became fairly well understood. But you can't navigate with a compass alone. For a compass to be useful you must have a map. What do pigeons use for their map?

Although Jon heard only that single lecture, William Keeton’s quest to crack the mystery of pigeon navigation – and by extension other long range animal navigators- permanently and powerfully aroused his own curiosity. The possibility of infrasound playing a role seemed plausible to him and remained in the back of his mind- a thought to be re awakened, more than 20 years later, after reading of disrupted pigeon races in Pennsylvania. Jon knew that if he could identify a source of infrasound that could have caused the disruption that he would have an important confirmation of the role of infrasound. And he did find the link – the infrasonic shockwave of the Concorde landing at JFK. Hagstrum.

Armed with the HARPA software, NOAA's detailed records of amospheric conditions and Keetons data, Jon will now be able to run analysis for correlations between pigeon navigation patterns and infrasound propagation under the the wind, temprature, pressure, humidity of that day, location and time. And of course be able to run new experiments. I'd say the role of infrasound in navigation is about to be irrefutably nailed down!

Next research frontier: How do tiny little pigeons heads have room for a mechanism able detect wave lenghts in the 100s of meters? Could it somehow be akin to the fractal antennae used in cell phones?

Can't wait for Jon's work on infrasound to be applied to other long distance animal navigator mysteries.