Of the 198 species of woodpeckers worldwide, 13 are found in Canada. The smallest and perhaps most familiar species in Canada is the Downy Woodpecker Picoides pubescens. It is also the most common woodpecker in eastern North America.
This woodpecker is black and white with a broad white stripe down the back from the shoulders to the rump. Its wings are checkered in a black and white pattern that shows through on the wings’ undersides, and the breast and flanks are white. The crown of the head is black; the cheeks and neck are adorned with black and white lines. Male and female Downy Woodpeckers are about the same size, weighing from 21 to 28 g. The male has a small scarlet patch, like a red pompom, at the back of the crown.
The Downy Woodpecker looks much like the larger Hairy Woodpecker Picoides villosus, but there are some differences between them. The Downy’s outer tail feathers are barred with black, unlike the Hairy Woodpecker’s, which are all white. The Downy is about 6 cm smaller than the Hairy, measuring only 15 to 18 cm from the tip of its bill to the tip of its tail. And the Downy’s bill is shorter than its head, whereas the Hairy’s bill is as long as or longer than its head length. The Downy’s name refers to the soft white feathers of the white strip on the lower back, which differ from the more hairlike feathers on the Hairy Woodpecker.
Woodpeckers are a family of birds sharing several characteristics that separate them from other avian families. Most of the special features of their anatomy are associated with the ability to dig holes in wood. The straight, chisel-shaped bill is formed of strong bone overlaid with a hard covering and is quite broad at the nostrils in order to spread the force of pecking. A covering of feathers over the nostrils keeps out pieces of wood and wood powder. The pelvic bones are wide, allowing for attachment of muscles strong enough to move and hold the tail, which is important for climbing.
Another special anatomical trait of woodpeckers is the long, barbed tongue that searches crevices and cracks for food. The salivary glands produce a sticky, glue-like substance that coats the tongue and, along with the barbs, makes the tongue an efficient device for capturing insects.