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.
Eastern bluebirds are very social birds. At times they gather in flocks of a hundred or more. However, they are territorial during the breeding season and may continue to defend a feeding area throughout the winter. Mating occurs in the spring and summer months. A mature female will typically raise two broods each season. Nests are constructed in trees within abandoned woodpecker holes or other cavities that provide adequate protection (usually several feet above ground).
Construction of the nest is done primarily by the female and takes approximately 10 days to complete. These nests are small, cup-like structures that are lined with grass, feathers, stems, and hairs. Each female lays 3 to 7 (average 4 to 5) light-blue or, rarely, white eggs. The female incubates the eggs, which hatch after 13 to 16 days. The young are altricial at hatching, meaning they cannot care for themselves upon hatching. The female broods the chicks for up to 7 days after hatching. Fledglings then leave the nest 15 to 20 days after hatching.