The Eastern Bluebird, Sialia sialis, is a medium-sized thrush found in open woodlands, farmlands and orchards.

Adults have a white belly. 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 (Sibley, 2000).

The population of the Eastern Bluebird declined seriously enough in the past century to reach critical status by the mid-1900s. The decline was due to:

1. Habitat destruction (loss of fields and nesting cavities in split-rail fences; clearing of dead trees)
2. Pesticide use
3. Nest predation by House Sparrows and European Starlings; both of which are non-native, introduced species.

Fortunately, the species was rescued by a network of birding enthusiasts who erected nesting boxes for Bluebirds, with close monitoring necessary to prevent House Sparrows from nesting in them. They remain thoughtful of conservation, however, with competition still prevalent from other species (for e.g. Tree Swallows, which are a native species and which also nest in cavities) and in certain states of the US they can still be difficult to spot. It is worth noting that due to the increase in their numbers in the past few decades, they are not protected under CITES or U.S. Endangered Species Act.

The Bluebird is the state bird of Missouri and New York.

The Eastern Bluebird is also found in Bermuda, where the population may constitute a sub-species. Bermuda Bluebirds have become endangered by the loss of 8 million Bermuda cedar trees in the 1940s, and by nest predation from introduced Sparrows, Starlings, and Kiskadees. Kiskadees, introduced in 1957, have also contributed to declines of other species, such as the Cardinal and the Catbird. In 1987, Hurricane Emily destroyed much of Bermuda's forest habitat, adversely affecting the Bluebird and other tree-dependent species.

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 blackberries, bayberries, fruit of honeysuckle, Virginia creeper, red cedar, 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.

Insects and other invertebrates: grasshoppers, crickets, katydids, beetles, earthworms, spiders, millipedes, centipedes, sow bugs, and snails

Plants and Fruits: dogwood, hawthorn, wild grape, sumac seeds, hackberry seeds, blackberries, bayberries, honeysuckle, red cedar, pokeberries, and Virginia creeper

These plant species may be used to enhance vegetation that already exists in and along open areas, brush and fence rows, and woodlots. Adding these species to those currently existing will enhance both food and insect availability for eastern bluebirds.