The Western Bluebird (Sialia mexicana) is a small North American thrush, 5.9 to 7.1 inches in length. Adult males are bright blue on top and on the throat with an orange breast and sides, a brownish patch on back, and a gray belly and undertail coverts. Adult females have a duller blue body, wings, and tail than the male, a gray throat, a dull orange breast, and a gray belly and undertail coverts. Immature western bluebirds have duller colors than the adults, they also have spots on their chest and back, and a white eye ring.
They are sometimes confused with other bluebirds, but they can be distinguished without difficulty. The western bluebird has a blue (male) or gray (female) throat, the eastern bluebird has an orange throat, and the mountain bluebird lacks orange color anywhere on its body. It has a stocky build, and a thin straight beak with a fairly short tail.
The western bluebird pounces on the ground when looking for food, such as worms and berries. It also flies to catch aerial prey, like insects, when available.
The western bluebird has adapted to coniferous forests, farmlands, semi-open terrain, and desert to survive. The year-round range includes California, the southern Rocky Mountains, Arizona, and New Mexico in the United States, and as far south as the states of Oaxaca and Veracruz in Mexico. The summer breeding range extends as far north as the Pacific Northwest, British Columbia, and Montana. Northern birds can migrate to the southern parts of the range; southern birds are often permanent residents.
They nest in cavities or in nest boxes, competing with tree swallows, house sparrows, and European starlings for natural nesting locations. Because of the high level of competition, house sparrows often attack western bluebirds for their nests. The attacks are made both in groups or alone. Attacks by starlings can be reduced if the nesting box opening is kept to 1.5 in (38 mm) diameter to avoid takeover.
These photos were taken at or near our next box in Costa Mesa. We feed them daily with meal worms from Rainbow Worms in Compton, CA. They are fed every afternoon at 3:30. They begin to congregate near the nest a 3:15. Their watches are almost better than ours.
For more photos of these Western Bluebirds see www.Comingsbirds.com/2017Birds