Indigo Bunting (Passerina cyanea) Robert B. Payne
Kensington Metropark, MI. 5/22/2009 © Jim Ridley (Click to view a comparison of Atlas I to II)
In late spring and through the summer, the survey blocks account for this decrease in birds in these survey areas. songs of Indigo Buntings are heard throughout
Michigan. The bright blue males are Breeding Biology conspicuous as they sing high on their perch in Males sing and set up breeding territories in trees. The brown females remain out of sight in Michigan when they return from their wintering the bushes and weeds where they nest. The area from early May to June. They breed shortly buntings migrate in spring across the Gulf of after their arrival and continue to breed through Mexico and along the Caribbean lowlands of early summer and into late July and August in Mexico, and in autumn and winter they return to the more humid habitats (Payne 2006). Females Mexico, Central America and the West Indies. build the nests within a day or two of their During the breeding season in Michigan they eat arrival in spring, or they wait a couple of weeks mainly insects and they also take seeds, buds after their arrival (Carey 1982). The latest and berries (Payne 2006). seasonal reports of breeding in Michigan are
fledglings in parental care into early September Distribution (Payne 2006). In the northern part of their range, Indigo Buntings are widespread throughout buntings may have time to nest only once in a Michigan. They live in shrubby habitats and season (Binford 2006). Territory size is 0.3 to often choose a site where blackberries and eight hectares and is larger in swampy habitats. dogwood provide a place to nest. They also nest Although the birds live in pairs in the breeding in rank forbs with branched stems that support a season, females often mate outside the pair nest, and where several vertical stems are bound bond, as both genetic markers and morphology together to support the nest, as in goldenrods. show about 30% of nestlings had a genetic Their distribution remained stable from MBBA father who was not their mother's social mate I through MBBA II in most townships in the (Westneat 1987, 1988, 1990; Payne and Payne state, with an 11% increase in occurrence in 1989). Females rear their brood until the young townships in the UP. The decrease in fledge; some older males help the female care distribution in survey blocks in the NLP and for the young after they leave the nest. About SLP appears to be a matter of scale; the survey 15% of the males attract more than one female blocks are more fine-grained than townships. to nest on their territory in a season. A female Perhaps the more local changes in habitat in nests repeatedly in a season either with the same
© 2010 Kalamazoo Nature Center Indigo Bunting (Passerina cyanea) Robert B. Payne male or with a change of male and territory. Abundance and Population Trends Occasionally even a first year female succeeds (Click to view trends from the BBS) in raising three broods (Payne 1989, 2006). Indigo Buntings have been widespread and common in Michigan for many years. Barrows Most buntings do not return to the nest site (1912) noted them in nearly every part of the where they were born, they usually settle at least state except Isle Royale. Breeding density in several kilometers from that site. Nevertheless, southern Michigan has been estimated at as many buntings return to breed in their natal many as 35 breeding pairs per 100 hectares in area, within 2-4 kilometers of the nest site Cass County and 15 breeding pairs per hectare where they were born (Payne 1991). These in Livingston County (Payne 2006). During first-year males sing songs unlike their fathers' MBBA I they were found in 94% of the songs, and they learn their songs from an adult surveyed townships in the SLP, 91% in the NLP male on the territory next to their own first and 67% in the UP. During MBBA II they were breeding territory. Females usually mate with a recorded in 94%, 92% and 77% of surveyed male whose song is unlike their father's song, townships respectively, suggesting an increase although a few mate with their father; only in the UP. Breeding Bird Survey (BBS) routes about 1% mate with a close family relative. show higher densities (more than 20 birds per Older returning males usually settle on their route) in the northwestern LP from Kalkaska territory of the previous year, while females and Crawford north to Charlevoix and often settle on a new territory rather than re- Cheboygan Counties and in the southwestern LP pairing with their old mate even when he returns from Allegan, Barry and Calhoun to Cass and to his old territory (Payne and Payne 1993, St. Joseph Counties. In this region the deciduous 1996). In the first half of the breeding season woodlands and shrubby vegetation are mixed about a third of bunting nests are brood- with small farms and provide nesting areas parasitized by Brown-headed Cowbirds; their along roadsides. Densities are lower (fewer than later nests are free of cowbird parasitism (Payne 10 birds per BBS route) in the more wooded and Payne 1998). Overall, about half the nests NLP and the boreal coniferous forests of the fledge at least one bunting, most other nests are UP. In neighboring Wisconsin the proportion of lost to a predator (Payne 1989, 2006). Although survey blocks (88.8%) with Indigo Buntings they avoid predation of their eggs and young by (Cutright et al. 2006) is similar to that in concealing their nests, females themselves may Michigan (88.1%). Densities in Ontario, like flush from a nest more quickly when their nests those in Michigan, decrease with latitude, with are less well concealed and they see a predator 7.2 buntings per route in the southern Carolinian approaching the nest (Burhans and Thompson Region, 4.6 in the Lake Simcoe-Rideau Region 2001). Adult survival is 55% for males and 40% and 0.1 in the Southern Shield Region (Cadman for females; the oldest known male was banded et al. 2007). In Michigan, no significant changes as a one-year bird and returned to the same in numbers were detected in BBS routes from territory for the next ten years (Payne and Payne 1966 through 2006; while throughout the 1989, 1990, 1996). bunting's range a small but significant decrease of 0.6% was noted from 12.4 birds per route in 1966 to 11 birds in 2004 (Sauer et al. 2008).
Indigo Buntings are scarce or absent in urban areas, in intensively cultivated lands, and in heavily forested habitats. They settle in abandoned farm fields and roadside edge within
© 2010 Kalamazoo Nature Center Indigo Bunting (Passerina cyanea) Robert B. Payne a few years after the land is abandoned by Payne, R.B. 1991. Natal dispersal and humans. Where swamps and abandoned fields population structure in a migratory songbird, remain as shrubby habitat due to browsing by the Indigo Bunting. Evolution 45: 49-62. white-tailed deer, the buntings may appear over Payne, R.B. 2006. Indigo Bunting (Passerina more than 60 years (Sutton 1959, Payne 2006). cyanea). The Birds of North America Online They disappear where areas are turned into (A. Poole, Ed.), 66 pp. Ithaca: The Birds of cities and residential development, where farms North America 4:
© 2010 Kalamazoo Nature Center Indigo Bunting (Passerina cyanea) Robert B. Payne
Westneat, D.F. 1988. Male parental care and extra-pair copulations in the Indigo Bunting. Auk 105: 149-160. Westneat, D.F. 1990. Genetic parentage in the Indigo Bunting: a study using DNA fingerprinting. Behavioral Ecology and Sociobiology 27: 67-76.
Suggested Citation
Payne, R.B. 2010. Indigo Bunting (Passerina cyanea). In Chartier, A.T., J.J. Baldy, and J.M. Brenneman (eds.). 2010. The Second Michigan Breeding Bird Atlas. Kalamazoo Nature Center. Kalamazoo, MI. Accessed online at:
© 2010 Kalamazoo Nature Center