Bird of the Week

Photo courtesy Charles Martinez

This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the Williamson’s sapsucker.

Primary cavity nesters like the Williamson’s sapsucker, who excavate a new nesting cavity every year, provide important habitat for other cavity nesting birds who raise their young in abandoned holes. Williamson’s sapsuckers nest in coniferous and mixed forests in the mountains from the Rockies westward. Northern populations may migrate as far as southern Mexico for the winter, while birds nesting further south may only move to a lower elevation.

In most woodpecker species, males and females appear similar, differing only in color on the head. Not so with the Williamson’s sapsucker. In fact, the male and female are so different in appearance that they were originally thought to be two different species. Not until a pair were observed at the same nest were they determined to be the same bird.

The male is velvety black above with vertical white wing patches, two white stripes on the face, a red throat patch and yellow belly. The equally attractive female has fine black and white barring on her back, a brown head, black chest patch and yellow patch on her belly.

Williamson’s sapsuckers drill neat, tiny holes in the trunks of conifers to draw out the sap. They don’t actually suck the sap, but lick it with their tongues, additionally eating the insects trapped in the sticky liquid. Ants are a large part of their diet, especially during nesting season. Why the sap doesn’t glue the bird’s bill shut is still a mystery, but scientists speculate that a substance in these birds’ saliva keeps the sap from making a sticky mess.

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