Prehistoric Passenger Pigeons - A Mystery

Over the weekend I picked up a copy of 1491 by Charles Mann. This is a fascinating book for those interested in New World archaeology and natural history. Its basic message is that the environment encountered by Europeans at initial contact was not an edenic natural paradise but was an anthropogenic construct. In other words, the environment was "manufactured" by the Native Americans to suit their needs using a wide variety of practices. This is not a new concept, but Mann does us all a service by collecting information from a wide variety of individual research projects by archaeologists and biologists into an accessible compendium. Portions of this book first appeared in the Atlantic in 2002, an article many of us read and enjoyed. This book is dense with information and speculation and I'm sure will provide fodder for future posts by Steve and me.

One interesting topic addressed in 1491 is the mystery of the passenger pigeon. The natural history of the passenger pigeon is a particular interest of Steve's (page down to A Feathered Tempest) and discussion on this topic first put us in communication. Steve's treatment gives detailed data, but the condensed version is that in the Eighteenth and Nineteenth centuries in eastern North America, passenger pigeons flew in flocks of tens of millions, darkening the sun, crushing tree limbs, and wreaking havoc in the environment wherever they ventured. According to one expert estimate, in the first quarter of the Nineteenth century, one out of every four birds alive on this continent was a passenger pigeon.

The sad but well-known story is that these birds were relatively quickly hunted to extinction. The last passenger pigeon died in captivity in the Cincinnati Zoo in 1914.

Projecting these tremendous passenger pigeon populations backward into prehistory, one would assume that they would have provided a ready food source for Native Americans in their range - whereupon comes our mystery.

I attended a presentation at the Society for American Archaeology annual meeting last spring by Dr. Ed Jackson of U. of Southern Mississippi on passenger pigeon remains in prehistoric archeological sites in the eastern US. Jackson's conclusion was that there were actually quite few such remains, a surprising development. In this case it is not a matter of preservation, as these sites had plenty of other bird bones.

In 1491, Mann presents the same conclusions with data from different researchers who used a smaller sample size than Jackson. Mann believes that the Indians would have eaten pigeons if they were available in any quantity, and concludes that their populations in this period were small or more would be seen in archaeological deposits. Mann theorizes that as humans, deer, passenger pigeons, and other animals were all competitive consumers of mast (acorns & nuts) from eastern forests, when human populations fell due to introduced European diseases, the equation of mast consumers fell out of balance and pigeon populations boomed. Therefore, massive passenger pigeon flocks are a post-European settlement phenomenon.

I have seen enough examples in the archaeological record where plentiful food resources were completely ignored by prehistoric Indians (subject of a future post) to immediately leap to the conclusion that prehistoric pigeon populations were small. But it is a genuine mystery and a fascinating subject for future discussion and research.