The Eastern Bluebird (Sialia sialis) is a small thrush found in open woodlands, farmlands and orchards, and most recently can be spotted in suburban areas. It is the state bird of Missouri and New York. This species measures 16–21 cm (6.3–8.3 in) long, span 25–32 cm (9.8–13 in) across the wings and weigh 27–34 g (0.95–1.2 oz). Adult males are bright blue on top and have a reddish brown throat and breast. Adult females have lighter blue wings and tail, a brownish throat and breast and a grey crown and back. Eastern Bluebirds are found east of the Rockies, southern Canada to the Gulf States and southeastern Arizona to Nicaragua. The bright blue breeding plumage of the male, easily observed on a wire or open perch, fluttering down to the mowed grass to capture a grasshopper, cricket or beetle makes this species a favorite of birders. The male’s call includes sometimes soft warbles of jeew or chir-wi or the melodious song chiti WEEW wewidoo. Approximately two-thirds of the diet of an adult eastern bluebird consists of insects and other invertebrates. The remainder of the bird’s diet is made up of wild fruits. Favored insect foods include grasshoppers, crickets, katydids, and beetles. Other food items include earthworms, spiders, millipedes, centipedes, sow bugs and snails. Fruits are especially important when insects are scarce in the winter months. Some preferred winter food sources include dogwood, hawthorn, wild grape, and sumac, and hackberry seeds. Supplemental fruits eaten include black raspberries, bayberries, fruit of honeysuckle, Virginia creeper, Eastern Juniper, and pokeberries. Bluebirds feed by perching on a high point, such as a branch or fence post, and swooping down to catch insects on or near the ground. The availability of a winter food source will often determine whether or not a bird will migrate. If bluebirds do remain in a region for the winter, they will group and seek cover in heavy thickets, orchards, or other areas in which adequate food and cover resources are available.
