Nesting sites are located in dense shrub or a low tree, generally 0.3–1 m (0.98–3.28 ft) above the ground, but rarely up to 9 m (30 ft). In the western part of their range, they often hybridize with the lazuli bunting. These birds are generally monogamous but not always faithful to their partner. In captivity, since it cannot migrate, it experiences disorientation in April and May and in September and October if it cannot see the stars from its enclosure. The indigo bunting often migrates during the night, using the stars to navigate. Migration takes place in April and May and then again in September and October. In areas where the ranges of the lazuli bunting and the indigo bunting overlap, the males defend territories from each another. Each male has a single complex song, which he sings while perched on elevated objects, such as posts, wires, and bush-tops. The song of the male bird is a high-pitched buzzed sweet-sweet chew-chew sweet-sweet, lasting two to four seconds, sung to mark his territory to other males and to attract females. A high-pitched, buzzed zeeep is used as a contact call when the indigo bunting is in flight. A sharp chip! call is used by both sexes, and is used as an alarm call if a nest or chick is threatened. The indigo bunting communicates through vocalizations and visual cues. It has occurred as a vagrant in Antigua and Barbuda, Barbados, Denmark, Ecuador, Germany, Iceland, Ireland, Netherlands, the Netherlands Antilles, Saint Pierre and Miquelon, Serbia and the United Kingdom. The winter range begins in southern Florida and central Mexico and stretches south through the West Indies and Central America to northern South America. The breeding range stretches from southern Canada to Maine, south to northern Florida and eastern Texas, and westward to southern Nevada. The habitat of the indigo bunting is brushy forest edges, open deciduous woods, second growth woodland, and farmland. In the adult female, the beak is light brown tinged with blue, and in the adult male the upper half is brownish-black while the lower is light blue. The immature bird resembles the female in coloring, although a male may have hints of blue on the tail and shoulders and have darker streaks on the underside. It has indistinct wing bars and is faintly streaked with darker markings underneath. The adult female is brown on the upperparts and lighter brown on the underparts. In fall and winter plumage, the male has brown edges to the blue body and head feathers, which overlap to make the bird appear mostly brown. The wings and tail are black with cerulean blue edges. During the breeding season, the adult male appears mostly a vibrant cerulean blue. The indigo bunting is a smallish songbird, around the size of a small sparrow. Evolving to reduce size may have allowed buntings to exploit grass seeds as a food source. This timing, which is consistent with fossil evidence, coincides with a late- Miocene cooling, which caused the evolution of a variety of western grassland habitats. This genetic study shows these species diverged between 4.1 and 7.3 million years ago. The indigo bunting is the sister of two sister groups, a “blue” ( lazuli bunting and blue grosbeak) and a “painted” ( Rosita's bunting, orange-breasted bunting, varied bunting, and painted bunting) clade. However, according to sequencing of the mitochondrial cytochrome-b gene of members of the genus Passerina, it was determined that the indigo bunting and lazuli bunting are not, in fact, sister taxa. They were declared to form a superspecies by the American Ornithologists' Union in 1983. The indigo bunting is closely related to the lazuli bunting and interbreeds with the species where their ranges overlap, in the Great Plains. The current genus name, Passerina, is derived from the Latin term passer for true sparrows and similar small birds, while the species name, cyanea, is from the Latin word meaning dark or sea blue. It was originally described as Tanagra cyanea by Linnaeus in his 18th-century work, Systema Naturae. The indigo bunting is included in the family Cardinalidae, which is made up of passerine birds found in North and South America, and is one of seven birds in the genus Passerina.
0 kommentar(er)
