Woodland Trails: The passenger pigeon story
The passenger pigeon has always fascinated me. Larger than a mourning dove, the passenger pigeon was thick in 1800s. So much so that it did actually blacken the sky for miles and miles and miles. How much so? Here is an account of John James Audubon.
"I dismounted, seated myself on an eminence and began to mark with my pencil, making a dot for every flock that passed. In a short time, finding the task which I had undertaken impracticable, as the birds poured in in countless multitudes, I rose, and counting the dots then put down, found that 163 had been made in twenty-one minutes. I traveled on, and still met more the farther I proceeded. The air was literally filled with pigeons; the light of noonday was obscured as by an eclipse, the dung fell in spots, not unlike melting flakes of snow; and the continued buzz of wings had a tendency to lull my senses to repose. ...Before sunset I reached Louisville, distance from Hardensburgh fifty-five miles. The Pigeons were still passing in undiminished numbers, and continued to do so for three days in succession."
Hard to believe so many birds in the sky at one time. Harder yet to believe that they are no longer present in our landscape. How could so many disappear? Where did they go and why did they become extinct? And more was disappearing at this time than the passenger pigeon. American bison were being eradicated and so were the Eskimo curlew, the sandhill crane and whooping cranes. The bison, sandhill, curlew and whoopers are still around, but the pigeon is long gone.
Audubon also mentioned: "Their great power of flight enables them to survey and pass over an astonishing extent of country in a very short time. This is proved by facts well known. Thus, pigeons have been killed in the neighborhood of New York, with their crops full of rice, which they must have collected in the fields of Georgia and Carolina, these districts being the nearest in which they could possibly have procured a supply of that kind of food. As their power of digestion is so great that they will decompose food entirely in twelve hours, they must in this case have traveled between three and four hundred miles in six hours, which shows their speed to be at an average of about one mile in a minute. A velocity such as this would enable one of these birds, were it so inclined, to visit the European continent in less than three days."
I read of this report from a resident in St. Paul in 1884. "On June 2 a great flock of pigeons flew over St. Paul at dawn. The birds were so low that many were killed with clubs and stones. The ordinance against the use of firearms within the city limits was discarded. Several people killed three dozen birds on their own premises. Those who got to the bluffs got 50 or 60 in an hour. All agreed that 'much exciting sport had never been seen in the city before.'"
Passenger pigeons were for sale on the market and hunted by market hunters as well. But many people took advantage of robbing the young birds from their nests as squabs that were a much preferred food as this account from an old hand written journal would indicate.
"Hundreds were taken by large crowds of men, women and children who 'made the forests ring with their merry shouts. Strong men shook the saplings, little boys climbed the trees and women filled their aprons with young birds. All infant birds that could not fly made their way into the pot. Pigeons were cooked in every style with divers and sundry nightcaps. It was also reported that, "Stewed squab in whisky sauce was not bad if you know when you had eaten enough."
Even though state laws prohibited the taking of nestlings for many species it seems that the laws were ignored for the passenger pigeon across the nation!
Pigeons were sold at the wharf in New York City for a penny apiece. One man in Pennsylvania caught 500 dozen in a net. In all probability the passenger pigeon was probably the most abundant bird on the planet. Some flocks were estimated at around 2 million birds! In Audubon's report it is estimated that 300 million birds flew over his head in those three days. Their droppings were thick enough to kill everything growing on a forest's floor. But when numbers dropped too low, market hunting became an unprofitable adventure and there should have been enough of them left to survive but they didn't.
"Why, then, did the birds go extinct? No one knows for sure, but it appears that to survive they needed to nest in vast colonies. Perhaps this permitted them to "swamp" predators with their enormous numbers, so that the relatively few predators in the area of a roost were unable to make a significant dent in the huge breeding colonies. And since these colonies dispersed as soon as breeding was over, predators were prevented from building up their populations on the basis of such an ephemeral resource. In any case, the fate of the passenger pigeon illustrates a very important principle of conservation biology: It is not always necessary to kill the last pair of a species to force it to extinction."