In memoriam, September 1, 100 years ago
Once so numerous that “the light of noon-day was obscured as by an eclipse.” Audubon
One of the most successful species. In 1866, a flock later estimated to contain 3.7 billion pigeons passed through Ontario over several days. In 1895, the last wild passenger pigeon was shot.

Martha was 29 years old and had never lived in the wild.
Passenger Pigeon, 1824, Pittsburgh, A cream background, the female from a higher branch leans down feeding (billing) the male – blue head lifted, spotted blue coverlets, rose neck and breast.”
I take a bird neatly killed, put him up with wires, and when satisfied with the truth of the position, I take my palette and finish off the bird at one sitting.” Audubon
Extinction is part of evolution, but we have greatly speeded it up. Jarred Diamond suggests 25% of all higher life forms are in danger of becoming within the next 50 years unless there is a dramatic change in human behaviour.
The extinction has made Lyme disease a huge problem. When passenger pigeons were abundant, acorns, their specialised food, would have been too scarce to support large populations of deer mice, the main reservoir of Lyme disease today.
Threatened Species Day is a national day held each year on 7 September to commemorate the death of the last remaining Tasmanian tiger (thylacine) at Hobart Zoo in 1936. Not many will take a moment to think about what we have lost and what we are in the process of losing.
See Elizabeth Kolbert, The Sixth Extinction: An Unnatural History, Bloomsbury, 2014