Forty or fifty years ago, the red-winged blackbird was a bird of ponds, swamps, and bullrushes. It was known for building its nest only among bullrushes, protected by water away from prowling predators. The males sang their territorial song from the rushes or a nearby bush. But as the swamps were drained, there were fewer bullrushes in which to build.
Most unusually, the birds shifted their nests to the bushes themselves.
This change gave them new places to live, and I saw more of them. They remained fairly aggressive, singing from the bushes even when people went by. We saw more red-wings away from the water. They inhabited bushes at the edge of fields and in the Don Valley, where they were likely to buzz runners who came too close. I’ve seen them in heavily populated parks such as near paths at Cherry Beach and Clark Beach Park in Toronto. They have become quite accustomed to people going by a few metres away.
Now, this fall, I am seeing them make one more bold move: They are coming into the city parks. I saw this one near Moss Park in downtown Toronto, foraging among starlings and sparrows. I anticipate a rise in the red-winged blackbird population. Of course, there might be another explanation: desperation – a loss of habitat elsewhere – rather than enterprise and expanding ranges. However, most birds, no matter how desperate, won’t make the switch to city living.
This map from the U.S. Geological Survey’s “North American” Breeding Bird Survey. In fact it shows only birds of the U.S. and southern Canada and completely omits Mexico. The colours indicate percent changes per year in population from 1966 to 2003.