Western Bluebird

I thought that a good field mark for identifying Western Bluebirds was the male’s brown back. As you can see in the first photo, back color is an unreliable characteristic. Western Bluebirds have variably colored backs, from brown to all blue—like this one Erika and I found along the southern end of the Chehalis Bike Trail near Olympia on 8 July 2020. Instead you have to rely on the Western Bluebird’s blue throat and blue sides of the head. As their name implies, Western Bluebirds breed in western North America, while Easterns are found in the East. Both species are found in Mexico.

The final photos are of one of two young birds accompanying the adult pair. Sibley states that young Western and Eastern bluebirds are very similar. Western Bluebirds are socially monogamous. Both parents care for the young, but both sexes mate with other bluebirds. Young birds, therefore are not always related to both of their parents. Young birds, often males, are known to assist their parents raise subsequent offspring (Guinan et al. 2020).