Now is a great time to look for one of the most colorful songbirds in North America: the Painted Bunting. This small passerine bird, related to cardinals, is a familiar sight in some portions of the southern United States during the spring and summer. The adult male has a blue-violet head, a grass-green back, green wings, and red underparts, and the adult females and immature birds are distinctive in being an overall leaf-green shade. Male Painted Buntings display delayed plumage maturation, which means that they molt into full adult plumage in their second year. In their first year, they are often indistinguishable from females.
The two main breeding populations are the eastern Atlantic Coastal Plain population, from southern North Carolina to northeastern Florida, west to Georgia, and the western population, from east-central Mississippi to New Mexico, northward to Kansas and southern Missouri. Smaller numbers of breeding birds occur in the Black Belt Ecoregion of northeastern Mississippi and northwestern Alabama.
This species favors largely open habitats with cover in the form of either woodland edges or scattered groves of trees. Larger trees within the nesting territory are important; a recent study in Louisiana demonstrated that a higher percentage of tree canopy cover led to more nestlings successfully fledging. Tall trees also provide perches from which male Painted Buntings can sing their warbling songs and defend their territories against rivals and predators.
Painted Buntings are usually monogamous, although polygyny (or multiple females mated to one male) sometimes occurs. After breeding Painted Buntings select a nesting site, the female constructs the nest in vegetation, usually only a few feet above the ground. The nest-building process takes a few days, and the female bunting incubates her three to four eggs for around 11 days. She tends the nestlings by herself, feeding them caterpillars, grasshoppers, damselflies, and walking sticks, among other insects.
The nestlings fledge after about eight to nine days. At this stage, if the female starts a second brood, which is common but not universal, the male bunting may take over the parental duties for the first brood. In a study on St. Catherines Island, Georgia, 22% of fledged broods were fed by males.
Painted Buntings are vulnerable to the habitat fragmentation that usually results from land development. As patches of bunting habitat shrink and become more isolated, the birds become more exposed to predators, human activity, and even parasites—like the Brown-headed Cowbird, a widespread brood parasite. Cowbirds lay their eggs in other songbirds’ nests, leaving the hosts to raise the large, fast-growing young alongside their own nestlings. To further stack the odds in her offspring’s favor, a female cowbird will also generally remove an egg or a nestling of the host species before laying an egg of her own.
Although cowbirds were once restricted to short-grass plains in western North America, habitat fragmentation has opened more territory to them, allowing them to expand their range and parasitize species with which they never previously interacted. In a study in southern Oklahoma nearly 70 years ago, about a quarter of the Painted Bunting nests in the research sites contained cowbird eggs. However, in the affected nests, bunting young fledged at the same time or earlier than the cowbird young, which suggests that some populations may have adapted to cope with cowbird parasitism—an encouraging development. Eastern populations of Painted Buntings have been exposed to cowbirds for less time than western populations, but possibly they, too, will eventually evolve coping strategies.
Although Painted Buntings spend their springs and summers in temperature zones, they are Neotropical migrants, wintering in Mexico, Central America, southern Florida, the Bahamas, and Cuba. For birds in the western parts of the breeding range, fall migration begins in late July, but eastern birds generally migrate later, in September. In either case, there’s still plenty of time this summer to observe this colorful and fascinating species!
