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Before there were none

What was it like to witness a flock of passenger pigeons flying overhead? What did this spectacle look and sound like? Start by imagining a murmuration of starlings multiplied by a thousand times ...

starling flock
Although common starlings, Sturnus vulgaris, form large flocks (murmurations) in autumn, their flocks are hundreds, or (more likely) thousands of times smaller than the flocks created by extinct passenger pigeons, Ectopistes migratorius. Photograph: FLPA/Alamy

The passenger pigeon was driven to extinction (by people, of course) one hundred years and two days ago, when the last individual, a captive-bred individual named Martha, died at the Cincinnati Zoo on 1 September 1914.

One of the first things that astounds most people about passenger pigeons are their multitudes: we simply cannot wrap our minds around what a billion of anything might possibly look like. And estimates of passenger pigeon numbers vary from three to ten billion, with individual flocks numbering in the tens of millions to a billion or more individuals. What was it like to witness a flock of passenger pigeons flying overhead? What did this spectacle look and sound like? Even those who observed such events first-hand could not believe their eyes. But we can start by imagining a murmuration of starlings multiplied by ten thousand times ...

Since I am busily writing a review of Mark Avery’s book about passenger pigeons, I thought I’d share a few of the first-hand accounts that he quotes in his book, just to give you a vague idea of what the passenger pigeon flocks were like.

Although passenger pigeons were not noisy birds, they created quite a racket with their wings when they flew overhead in their millions, as we learn from Alexander Wilson, who wrote a series of observations about them in the early 1800s:

Happening to go ashore one charming afternoon, to purchase some milk at a house that stood near the river, and while talking with the people within doors, I was suddenly struck with astonishment at a loud rushing roar, succeeded by instant darkness, which, on the first moment I took for a tornado about to overwhelm the house and everything around in destruction. The people, observing my surprise, coolly said: ‘It is only the pigeons’”.

[as quoted by Mark Avery, A Message from Martha (2014), p. 65.]

But the massive flock was actually composed of numerous smaller (but still huge) groups of passenger pigeons. Here’s an observation written by Benedict Revoil about a flock he observed in the autumn of 1847 near Hartford, Kentucky:

...on emerging from the wood, I observed that the horizon was darkling; and that after having attentively examined what could have caused so sudden a change in the atmosphere, I discovered that the clouds -- as I had supposed them to be -- were neither more nor less than numerous flocks of pigeons. These birds flew out of range ... so I conceived the idea of counting how many troops flew over my head in the course of an hour. [...] In a short time the flocks succeeded each other with so much rapidity that the only way I could count them was by tracing manifold strokes. In the space of thirty-five minutes, two hundred and twenty bands of pigeons passed before my eyes. Soon the flocks touched each other, and were arrayed in so compact a manner that they hid from my sight the sun. The ordure of these birds covered the ground, falling thick and fast like a winter’s snow ...”

[as quoted by Mark Avery, A Message from Martha (2014), pp. 68-69.]

But how many birds might have been seen by Mr Revoil in that 35 minute observation? Here’s a mathematical assessment of a recollection of passenger pigeon flocks seen in the 1860s and 1870s in eastern Iowa, written in 1910 by W. J. McGee:

A rough estimate of the number of birds passing a given point in spring may be useful. The cross-section of an average flock was, say, a hundred yards from front to rear, and fifty yards in height, and when the birds were so close as to cast a continuous shadow there must have been fully one pigeon per cubic yard of space, or 5,000 to each linear yard of east-west extension -- i.e. 8,800,000 to the mile, or (with reasonable allowance for the occasional thinning of the flock) say 30,000,000 for a flock extending from one woodland to the other. Since such flocks passed repeatedly during the greater part of the day of chief flight at intervals of a few minutes, the aggregate number of birds must have approached 120,000,000 an hour for, say five hours, or six hundred million pigeons virtually visible from a single point in the culminating part of a single typical migration.”

[as quoted by Mark Avery, A Message from Martha (2014), pp. 70.]

This video animation by the Lost Bird Project might also give you some idea of what these flocks were like:

Passenger Pigeon Flock Overhead by Lost Bird Project.

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You may wish to read about a recently published scientific study that further explores the extinction of the passenger pigeon.

You may also wish to watch several videos that discuss Martha’s last homes.

Read my review of Joel Greenberg’s book about the history of the passenger pigeon, A Feathered River Across the Sky.

Read my review of Errol Fuller’s collection of rare photographs, art and other visual miscellany in his new book, The Passenger Pigeon.

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When she’s not got her nose in a book, GrrlScientist can also be found here: Maniraptora. She’s very active on twitter @GrrlScientist and sometimes lurks on social media: facebook, G+, LinkedIn, and Pinterest.

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