A Feathered River Across the Sky: the Passenger Pigeon’s Flight to Extinction
By Joel Greenberg
Most Canadians and Americans know that their continent was once blanketed with now-extinct passenger pigeons; some may even be aware that, unusually, we know the precise date of their final disappearance: Sept. 1, 1914, when Martha, the last of her kind, died in the Cincinnati Zoo. But few of us can be aware of the scale of the loss.When Europeans arrived here, the pigeons made up at least a quarter of the bird life north of Mexico; their passage could obscure the sun for days; a single flock that flew by Toronto in 1860 contained as many as three billion individual birds; the largest nesting site on record extended over 2,200 sq. km; their descent from flight was a riot of destruction for themselves (the first to land were often crushed by the sheer mass of latecomers) and for the site—wide swaths of forest looked to observers as though they had been visited by a guano-fuelled tornado.
They were beautiful, too. Up to half a metre in length, the more colourful males had slate-blue upper parts and a throat and breast of copper glazed with purple, making them iridescent. Passenger pigeons were a sight to behold, in every sense, and were beheld by most North Americans, since their pathways regularly crossed over the continent’s most densely populated areas.
And then they were gone. In half a century, the passenger pigeon plunged from a single flock of billions to Martha. Even before the hunting became commercialized (pigeon meat provided cheap food for the poor and even for hogs), the killing was done on a mass and indiscriminate scale: hunters used sticks to push the oil-fat squabs out of their nests or chopped down trees with 20 or more nests; sometimes they set the trees on fire, cooking as well as killing the prey; shotgun blasts could take down five dozen at a time and nets could catch 800 at once. At an 1878 nesting site in Michigan, perhaps 50,000 birds were killed daily for almost five months. Often the market became glutted, and the meat valueless—in one incident during the 1880s, several tons of unsold birds were dumped into the Wisconsin River.
Nor, as Greenberg’s exhaustive account of endless greed and blind stupidity makes clear, do we yet fully realize what the passenger pigeon meant to the ecology of North America’s eastern woodlands. The cycle of destruction and renewal they brought the forests, the food they provided for animal predators, the fertilizing effect of their droppings, even the way they probably kept a check on the population of their chief competitors for acorns, white-footed mice, who are also the main host for the organism that causes Lyme disease, made the pigeons a keystone species. What’s left of our impoverished forests is probably still adjusting.