A small bird, the indigo bunting (Passerina cyanea) weighs only about half an ounce and measures approximately 5-1/2 inches long. During the breeding season, males are brilliant blue with a darker blue crown. In winter, the male’s color fades until he appears more brown than blue. Females are drab brown, with faint wingbars. Like all finches, indigo buntings have short, conical bills.
The males’ lovely coloration is actually an optical illusion. Despite the fact that their bodies contain no blue pigment, light refraction gives their plumage an iridescent azure sheen. For this reason, the indigo bunting may appear to be different shades of blue, depending on the light. It’s commonly viewed as only as a black silhouette high in a tree.
Indigo buntings are common residents across eastern North America, from Canada to Texas and Florida. They spend the winter in Mexico, central America, northern South America and the Caribbean.
During the breeding season, indigo buntings forage for insects, seeds and berries. Their appetite for crickets, grasshoppers, cicadas, mosquitoes, wasps, ants, flies, beetles, caterpillars and aphids make these birds welcome visitors to farm fields and orchards. Their favorite seed choices include those of dandelion, goldenrod, lamb’s-quarters, smartweed, asters and thistle. They also favor small fruits like raspberries and elderberries. Their winter diet consists mainly of various grass seeds.
Largely solitary birds, indigo buntings feed alone during the breeding season. During the winter, they become more gregarious, roosting as a band at night. Even then, they spend their days hunting for food either alone or in small groups. This species has a long migratory route, flying as far as 2,000 miles between their breeding grounds and wintering spots. They migrate largely at night, using stars as a navigation guide.
Indigo buntings breed between May and September. They often raise more than one brood, and it’s not uncommon for them to switch nests and/or mates in midseason. Although the male is relatively quiet during courtship, he sings constantly once his mate begins nest construction, declaring their territory to other males. After the female chooses a site, she builds a nest of leaves, sticks, grasses and strips of bark, in which she lays one to four eggs. Nests are often located in berry bushes, barberry or wild rose thickets, or saplings of hackberry, elm or maple trees. Indigo bunting pairs separate soon after the eggs are laid, and the female raises the brood by herself. The young leave the nest 12 to 13 days after hatching, and become fully independent at about four weeks of age.
Males arrive in nesting areas several days before the females, where they begin singing in defense of territory. They look for the highest perch in the vicinity from which to announce their dominion. They produce a fast warble that sounds like “sweet-sweet, where-where, here-here, see-it see-it.” Males sing from spring arrival through mid-August or even later. Their flight song is similar to that of the goldfinch.
Attracting to Your Property
Be watchful for these birds in spring and fall, when they may pay a short visit during their long north/south migration. You have the best chance of inviting their summer-long residence if your property offers the mix of woodland and open areas they prefer for nesting. Indigo buntings can be lured to feeders with nyger, millet or even grass seed, which they relish.
Lazuli bunting (Passerina amoena):
Named for the beautiful lapis lazuli gemstone, this western counterpart of the indigo bunting is found from British Columbia to Baja. The two species overlap somewhat in the Great Plains. In summer, male lazuli buntings are turquoise blue with a rust colored breast and white belly; females are dull brown. This bird's song is similar to that of the indigo bunting, but with less repetition.
Painted bunting (Passerina ciris):
By far the most showy of the buntings, painted bunting males have a tropical appearance, with a deep blue-purple head, bright green back and bright red underside. Females are bright green, while young birds are drab green. The male has a sweet, high-pitched song. This species nests in the south central U.S. and along a strip of the southern Atlantic coast.
Cornell Lab of Ornithology: All About Birds - Indigo Bunting
National Audubon Society: Indigo Bunting
Thumbnail photo of male indigo bunting by Teddy Llovet
Female indigo bunting by chad horwedel
Goldfinch and bunting at feeder by jackanapes
Lazuli bunting by Carla Kishinami
Painted bunting by Dan Pancamo