Passerina cyanea
indigo bunting

Indigo buntings (Passerina cyanea) breed throughout eastern North America from the Great Plains eastward, south of the coniferous forest region. There are also some breeding populations in the western United States, including Utah, Arizona and California. Indigo buntings winter in the coastal regions of Mexico, Central America, northern South America and the Caribbean.

Indigo buntings breed in brushy and weedy habitats along the edges of farmed land, woods, road, power lines, railways and riparian habitats. They also breed in clearings in open deciduous woodlands, in weedy or abandoned agricultural fields, and in swamps. During migration they look for open grasslands and leafy trees similar to those in their winter habitat. In winter, indigo buntings choose open habitats, such as weedy fields, citrus orchards, savannas, weedy croplands and low second growth (Payne 1992).

Adult male indigo buntings are brilliant blue during the breeding season, with a darker almost purple crown. Females and young are brown with buff wingbars and only a tinge of blue on their tail and shoulders. Indigo buntings are small birds, from 11.5 cm to13 cm long and weighing 12 to 18 g. They have short, conical beaks and black or gray legs and feet. (Payne 1992, Robbins, Bruun and Zim 1983)

Indigo buntings can live up to 10 years in the wild.

Indigo buntings are generally solitary. During the breeding season, males establish and defend a territory 0.4 to 8 ha in size. Each territory may hold one or more females. During the winter, indigo buntings roost in a flock at night, but spend the days foraging alone or in small groups. There appears to be no dominance hierarchy within these groups. (Payne 1992)

Indigo buntings are migratory, and may fly as far as 2000 miles between their wintering and breeding grounds. They leave their breeding grounds in September and October, and leave their wintering grounds to return in late April and May. They migrate largely at night. (Payne 1992, Robbins, Bruun, and Zim 1983, Scientific American 1980)

Home Range

In one study, 10% of banded fledglings returned to breed within 1 to 2 km of their natal site (Payne 1992).

Indigo buntings use vocalizations and visual cues to communicate. Only male indigo buntings sing. Each male has one complex song that it sings, during the breeding season to advertise occupancy of a territory to other males and to attract females. Males may also court females by performing displays, such as the display in which a male struts in circles in front of a female with his wings spread and his head crouched.

During the breeding season, indigo buntings eat small spiders and insects, seeds of grasses and herbs, and berries. Major food items taken include caterpillars, grasshoppers, bugs, beetles, seeds and berries. In winter, indigo buntings eat small seeds, buds, and some insects. Their main food in winter is small seeds of grasses. They also frequent feeders, and eat the seeds of rice in rice fields. Indigo buntings do not appear to drink frequently, and may obtain sufficient water from their diet. (Payne 1992)

Indigo buntings feed alone during the breeding season and in flocks during the winter. They do not appear to store food for later consumption. (Payne 1992)

Although predation of adult indigo buntings surely occurs, specific predators have not been identified. Brooding females, eggs and young are vulnerable to predation from climbing predators, including raccoons, opossum, red fox, feral cats, blue jays and blue racers.

When a predator approaches a nest, adult buntings may feign injury and make a chip-chip-chip call to distract the predator and lure them away from the nest. They do not mob predators.

Perching birds (order Passeriformes) as a group play an important role in the earth's ecosystems. They consume many varieties and amounts of food and serve as food for others and hosts for parasites (Britannica, 1986). Indigo buntings affect the populations of the insects they eat, and help distribute seeds of the plants whose berries they eat. They also host at least one parasite; hippoboscid flies (Payne 1992).

There are no known adverse affects of indigo buntings on humans.

There is apparent aesthetic importance of songbirds like the Indigo bunting to bird watchers and listeners. This brightly colored species is commonly kept as a cage bird (Britannica, 1986).

Indigo buntings appear to be increasing in geographic range and density. They are protected under the U.S. Migratory Bird Act, but not under CITES or the U.S. Endangered Species Act.

Indigo buntings are occasionally killed for sport and food. They are also a popular cage bird in Europe and Mexico. (Payne, 1992)