All 3 of these birds are the same kind: Williamson's Sapsuckers. The two on the left are males and the one on the right is a female. Their coloring is very different, making it appear at first glance they are not the same kind of bird. However, if you compare other characteristics, it becomes evident that all three birds are much more alike than different. Dramatic differences in coloration between the different genders of birds of the same species is called plumage dimorphism.
Sapsuckers are woodpeckers with long straight strong bills for drilling into the bark of trees and long tongues for licking the woodboring insects out of an infected tree, making for a nice meal. They rarely perch upright but are usually seen clinging to the side of a tree or limb or climbing up and rarely down the trunks of trees. Very few other types of birds are capable of this type of action.
Sapsuckers use that same strong beak to drill large holes into trees and build nests within the cavity created. Once the woodpecker moves on to create new nests, these abandoned holes are used as nesting sites by other birds with weaker bills who couldn't create these safe openings. Birds using such nesting sites, like the Mountain Bluebird discussed earlier, are referred to as cavity nesters.
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Last updated: November 22, 2020