The Indigo Bunting is a small songbird native to North America. Its scientific name is Passerina cyanea. This brightly colored bird is known for the beautiful indigo blue color of the male’s feathers during breeding season. The females and juveniles have brown plumage. Indigo Buntings breed in the eastern and central United States and spend the winter in southern Florida, Central America, and the Caribbean. Their breeding habitat extends as far west as Texas, Oklahoma, Kansas, Nebraska, and South Dakota. This article will examine whether Indigo Buntings can be found in the state of Ohio.
Physical Description
The Indigo Bunting is a small-sized songbird, measuring 11.5–13 cm (4.5–5.1 in) long with a wingspan of 18–23 cm (7.1–9.1 in). The male has a conical bill and a long tail. During the breeding season, the adult male has spectacular, deep blue plumage on its head, back, wings, and tail. Only the underparts are brownish-white. This brilliant blue color comes from discrete melanin pigment granules suspended in the hairlike keratin structure of the feathers. When exposed to sunlight, these granules scatter blue light, leading to the perception of blue coloration.
Outside of the breeding season, the male’s blue plumage becomes obscured by brown feather tips. The adult female is mostly brown, like the non-breeding male, but with some darker streaking on the underparts. The female can be distinguished from the male by her brownish olive upperparts and buffy underparts. Both sexes have two pale wing-bars visible while flying. Juvenile birds resemble the adult female in coloration. The eyes of Indigo Buntings are brown.
Size and Shape
Indigo Buntings are stocky songbirds with short, thick, conical bills. They have relatively large heads and short tails. Their wings are short, rounded, and broad compared to other songbirds. When perched, Indigo Buntings often flick their tails open and closed.
Color Pattern
During the breeding season, the male’s brilliant blue coloration is unmistakable. The underparts are white on the chin, throat, and belly, with some faint brown streaking on the sides. The female is mostly nondescript brown, though she may show some faint blue on the wings and tail. Juveniles resemble the female, with brown upperparts and light underparts with streaking.
Range and Habitat
The Indigo Bunting has a breeding range that extends across much of the eastern and central United States. Its breeding habitat spans west to North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, and Texas. The species winters in Florida, Mexico, Central America, and the Caribbean islands.
Indigo Buntings prefer open scrubby habitat with scattered trees and shrubs across much of their range. They are often found along forest edges, power line cuts, overgrown fencerows, and roadside thickets. During migration, they may stop in wooded suburban yards that provide trees and open sunny spots. On the wintering grounds, they occur in open and semi-open areas with some trees or shrubs and grassy areas.
Breeding Range and Habitat
The Indigo Bunting’s breeding range covers most of the eastern United States from southern Maine west to Minnesota, and south to northern Florida and the Gulf Coast. In the west, the breeding range extends through Kansas, Oklahoma, and Texas.
Preferred breeding habitats include successional scrublands, forest edges, power line corridors, overgrown fields, and roadside thickets. They look for habitats with a mix of grasses, shrubs, and scattered trees. These buntings often breed in suburban yards, parks, and gardens if there is an area of native shrubs and unmowed grass.
Winter Range and Habitat
Indigo Buntings migrate out of most of the United States to spend the winter in Florida, Mexico, Central America, and the Caribbean islands. Their winter range centers around southern Mexico and Guatemala.
On the wintering grounds, Indigo Buntings use more open habitats than during breeding. They are found in agricultural areas, grasslands, coastal scrub, woodland edges, and open forests. They may gather in large foraging flocks in weedy fields or around feeders.
Migration Through Ohio
Ohio lies within the migration route of the Indigo Bunting. Large numbers pass through the state in May on their way to breeding territories farther north. The southbound migration occurs in August and September as they return to their wintering range. During migration, Indigo Buntings can turn up in a wide variety of semi-open and suburban habitats across Ohio.
Spring Migration
Indigo Buntings generally arrive in Ohio in mid to late April as they migrate north to their breeding grounds. The males usually precede the females by 1-2 weeks during spring migration.
Peak spring passage through Ohio occurs during May, with sightings frequent early in the month. Migrating Indigo Buntings forage in weedy fields, forest edges, scrubby areas, and suburban yards with native vegetation. Good birding sites during May include Magee Marsh, Oak Openings, Killdeer Plains, and Shawnee State Forest.
Fall Migration
Fall migration starts relatively early for Indigo Buntings. Southbound migrants begin passing through Ohio by late July and early August, with numbers increasing through the month. Like in spring, peak fall passage occurs in September.
Productive areas to find migrating Indigo Buntings in autumn include dense shrubby areas, weedy fields, and overgrown clearings. Cedar Point National Wildlife Refuge and Maumee Bay State Park are good sites to spot southbound migrants. By late September, most Indigo Buntings have left Ohio for their winter grounds.
Occurrence in Ohio
While Indigo Buntings are migratory songbirds that breed in more northern locations, a small number of pairs nest in Ohio each summer. The breeding population is scattered and localized, with highest densities found in some counties of southeastern Ohio. But sightings of territorial males confirm nesting in many other parts of the state.
Breeding Range in Ohio
Within Ohio, Indigo Buntings are most likely to breed in the southeastern part of the state. They have been documented nesting in Adams, Athens, Gallia, Jackson, Lawrence, Meigs, Scioto, and Vinton counties.
Elsewhere in Ohio, breeding territory mapping has detected scattered nesting by Indigo Buntings in Erie County of northern Ohio, Geauga County of northeastern Ohio, and Greene County in west-central Ohio. Small numbers likely nest sporadically in suitable habitat in other parts of the state.
Habitats Used for Breeding
During summer, male Indigo Buntings set up breeding territories in successional habitats with a mix of grasses, shrubs, and trees. Overgrown fields, power line cuts, forest openings, and edges are used. In Ohio, thickets along riparian corridors provide nesting habitat. Unmowed areas along roads or trails, or the edges of parks may also support breeding.
Timing of Breeding Season
Indigo Buntings arrive on their Ohio breeding grounds by late April or early May. Nest-building and egg-laying occurs from mid-May through late June. The female alone builds the nest and incubates the eggs. The young hatch after 11-14 days and fledge from the nest about 9-12 days later. Indigo Buntings generally raise two broods per season in Ohio, with the second brood fledging by late July or early August.
| Breeding Timeline for Indigo Buntings in Ohio | |
|---|---|
| Late April to Early May | Arrival on breeding grounds |
| Mid May to Late June | Nest building and egg-laying |
| May to July | First broods fledge |
| June to August | Second broods fledge |
Population Trends in Ohio
Breeding Bird Survey (BBS) data suggest Indigo Bunting populations have increased within Ohio since the route surveys began in 1966. The estimated population growth is about 2.1% per year between 1966-2015. However, population densities remain relatively low across most of the state.
Breeding Bird Survey Data
According to the Breeding Bird Survey, Indigo Buntings showed a significant positive population trend in Ohio between 1966 and 2015. The estimated rate of increase was 2.09% annually during that period.
The average number of Indigo Buntings detected per BBS route in Ohio increased from 0.5 birds/route in 1966 to 1.9 birds/route in 2015. This indicates higher abundance in recent years compared to when surveys began in the 1960s.
Current Population Estimate
Using data from the 2nd Ohio Breeding Bird Atlas conducted during 2006-2011, Indigo Bunting populations were estimated at approximately 82,000 breeding adults statewide. However, the atlas data showed densities remain below 1 bird/km2 across most of Ohio, indicating a localized and diffuse distribution.
Range Expansion
The observed population increase has been accompanied by a slow range expansion in Ohio. Comparison of the 1st and 2nd breeding bird atlases shows Indigo Buntings expanded their range northward and westward in the state over the past few decades. This growth corresponds with trends in other parts of the Midwest.
| Indigo Bunting Population Trends in Ohio | |
|---|---|
| 1966 | 0.5 birds/route on BBS surveys |
| 2015 | 1.9 birds/route on BBS surveys |
| 1966-2015 | Estimated 2.09% annual increase |
| 2006-2011 | ~82,000 adults estimated in 2nd Breeding Bird Atlas |
Behavior and Ecology
The Indigo Bunting is well-adapted to exist in early successional habitats. Despite their brilliant blue plumage, males use their song more than visual displays to defend breeding territories. These birds feed mainly on insects supplemented with seeds. Nesting occurs on or near the ground in dense shrubs or small trees. Indigo Buntings migrate at night and may orient by the stars.
Foraging
Indigo Buntings forage mainly in the lower parts of trees and shrubs or right on the ground. They eat small insects, especially caterpillars, grasshoppers, beetles, and flies. Spiders and snails are also eaten. In late summer and fall, Indigo Buntings shift to eating more seeds of grasses and weeds. At feeders, they may eat millet, unhulled sunflower seeds, and cracked corn.
Mortality and Threats
The bright blue males are vulnerable to predation from birds of prey when migrating. Collisions with buildings, towers, and vehicles also take a toll. Brown-headed cowbirds sometimes lay eggs in Indigo Bunting nests, though buntings often bury or remove the foreign eggs. In Ohio, major threats include habitat loss of early successional areas and forest fragmentation.
Territorial Behavior
Males establish breeding territories as soon as they arrive in spring. Although visually striking, males do not use elaborate visual displays. Instead, persistent singing from high perches advertises territory ownership. Males may counter-sing in boundary disputes but outright fights are rare. Females settle on a male’s territory to breed. The female alone builds the nest while the male perches nearby singing.
Migration
Indigo Buntings are nocturnal migrants that navigate using celestial cues. They migrate in flocks, occasionally making long non-stop flights over barriers like the Gulf of Mexico. Spring migration is more prolonged with frequent stopping to replenish fat reserves. Successful migration requires good energetic condition and suitable weather conditions.
Status as a Species of Conservation Concern in Ohio
Despite increasing population trends, Indigo Buntings remain listed as a Species of Conservation Concern in Ohio. Their localized distribution and reliance on disturbed habitats make them vulnerable to declines if land use changes reduce habitat availability. Indigo Buntings may benefit from habitat management focused on creating suitable successional areas.
Conservation Status
The Indigo Bunting is currently categorized as a Species of Conservation Concern in Ohio. It was also listed as a Species of Concern from 2002-2013 while awaiting review of its status.
Despite increasing numbers, conservation concerns remain due to the Indigo Bunting’s limited breeding distribution and reliance on ephemeral successional habitats within Ohio. Ongoing habitat management is important for maintaining suitable breeding areas.
Threats and Recommendations
Indigo Buntings are threatened by loss and degradation of scrubby successional areas in Ohio. Maintaining breeding habitat will require active vegetation management through techniques like mowing, grazing, prescribed fire, and brush clearing. Retaining patches of successional growth along fence lines, trails, ditches, and other marginal areas can provide habitat. Cluster house lots in new developments rather than spreading out over the landscape to retain open space.
Actions to Help
Concerned citizens can aid Indigo Buntings by:
- Keeping parts of your property unmowed or clearing overgrown areas
- Allowing natural regrowth of shrubs and small trees along edges
- Installing native shrubs and grasses in gardens
- Avoiding pesticide use which reduces insect prey
Land stewards should integrate periodic disturbance through mowing, grazing, or fire to maintain the vegetative density and height preferred by Indigo Buntings.
| Conservation Status and Recommendations for Indigo Buntings in Ohio | |
|---|---|
| Conservation Status | Species of Conservation Concern |
| Threats | Habitat loss of successional areas |
| Recommended Actions | Active vegetation management for disturbance; Retain overgrown patches in marginal areas |
Where to See Indigo Buntings in Ohio
Some locations where birders can look for Indigo Buntings in Ohio include Shawnee State Forest, Edge of Appalachia Preserve, Killbuck Wildlife Area, Oak Openings Preserve Metropark, and Magee Marsh Wildlife Area. Checking overgrown fields, powerline corridors, forest clearings, and scrubby thickets may reveal territorial males in summer. During spring and fall migration, migrant Indigo Buntings use a wider variety of semi-open habitats across the state.
Shawnee State Forest
The Shawnee State Forest encompasses over 59,000 acres across Scioto and Adams counties in south-central Ohio. This state forest provides extensive breeding habitat for Indigo Buntings, including reverting agricultural fields, recent timber harvest areas, and overgrown utility right-of-ways crisscrossing the forest. Birders may spot males singing from their territories along Forest Road #5 or the Turkey Ridge Trail.
Edge of Appalachia Preserve
The Nature Conservancy’s Edge of Appalachia Preserve hosts breeding Indigo Buntings in several of its units. The Banta-Davis unit near West Union and McDonald Bluegrass unit near Felicity offer shrubby powerline right-of-ways where birders can listen for singing males during summer. Regrowth clearings at the Brightman Ridge and Stonehouse units also provide habitat.
Oak Openings Preserve Metropark
This unique park northwest of Toledo has savanna and sand prairie habitats. Indigo Buntings breed in the shrub thickets, planted hedgerows, and edges between open and wooded areas. The Girdham Road area may have territorial males. Large numbers of migrants pass through the park in May and September.
Killbuck Wildlife Area
This state wildlife area encompassing over 11,000 acres attracts breeding Indigo Buntings to the disturbed scrubby areas of former strip mines. The dikes between wetlands offer dense nesting cover. Old fields and grasslands provide feeding and nesting habitat. Take the Zuercher Road south from Route 250 to reach the interior of the wildlife area.
Magee Marsh Wildlife Area
Though better known as a top migratory hotspot, Magee Marsh also has suitable breeding habitat for Indigo Buntings. Patches of shrubby regrowth, dike edges, and wetland-upland transition zones may harbor territorial males. Bird the Estuary Trail or Sportsmans Trail in summer to try for breeding Indigo Buntings. Large numbers also pass through during spring and fall migration.
Conclusion
In summary, the migratory Indigo Bunting does occur in Ohio, especially during spring and fall migration. Small populations nest sporadically across the state, mostly in regrowing clearings in the southeast. But the brilliant blue males can turn up in any scrubby, semi-open habitat during migration. Careful management of succession is needed to maintain breeding habitat given this species’ conservation status. Birders can find migrating and breeding Indigo Buntings by exploring overgrown areas like reverting fields, forest edges, power cuts, and thickets along dikes and trails.
