Ovenbirds breed in large, mature broadleaf or mixed forests from the Mid-Atlantic states to northeastern British Columbia. They set up summer territories where the leaf canopy overhead inhibits underbrush and provides deep leaf litter hosting plenty of invertebrates. Extensive, uninterrupted forests with relatively closed canopies 50 to 70 feet above the ground seem ideal. Even fairly large forest patches of 250 to 2,000 acres may not be able to support Ovenbird populations unless larger forests are close by. Ovenbirds are less picky about their winter habitats. They avoid open fields and cultivated areas, but where mature forests are unavailable, they can live and feed among shade coffee trees or mangroves, on dry scrubland or regenerating agricultural land, and in moist upland or dry lowland forests. They still favor leaf litter for hunting invertebrates, but they can forage in grasses or on rocks or mud near water. Back to top
Ovenbirds eat mainly forest insects and other invertebrates: a range of adult beetles and larvae, ants, caterpillars, flies, and other insects. Most of these are hunted in leaf litter, some on leaves, and a few on bark or in the air. Parents feed ground beetles and larvae to nestlings. Ovenbirds can alter their feeding habits to forage in trees and shrubs in response to a novel food source, like an outbreak of spruce budworms. In winter habitats, Ovenbirds' food flexibility matches their habitat flexibility. They may add seeds to their diets and specialize in locally abundant prey like ants. They may also hunt insects and grubs in short grasslands or on rocks and mud near water. Back to top
The female Ovenbird builds a nest in thick leaf litter on the open forest floor at least 60 or 70 feet from the forest edge. She chooses a spot under or near a small break in the canopy, often near where a tree has fallen or near regrowth from some other disturbance
The female clears a circular spot in forest floor litter and over the next 5 days weaves a domed nest of dead leaves, grasses, stems, bark, and hair. The nest’s squat oval side entrance is hidden from above and generally faces downhill if the nest is built on a slope. The inner cup is just 3 inches across and 2 inches deep, lined with deer or horse hair. The outer dome, camouflaged with leaves and small sticks, may be up to 9 inches across and 5 inches high. Its resemblance to an outdoor bread oven with a side opening gives the Ovenbird its name.
|Clutch Size:||3-6 eggs|
|Number of Broods:||1-2 broods|
|Egg Length:||0.8-0.9 in (1.9-2.2 cm)|
|Egg Width:||0.6-0.6 in (1.4-1.6 cm)|
|Incubation Period:||11-14 days|
|Nestling Period:||7-10 days|
|Egg Description:||White with reddish-brown spots and speckles.|
|Condition at Hatching:||Helpless, covered in dark gray to pale brown down, with eyes closed but mouths opening in response to noise.|
Male Ovenbirds establish late-spring territories in vigorous, prolonged encounters with other males. They vocalize loudly and chase competitors, but rarely make physical contact. Males defend established territories primarily by singing from perches in the low canopy. A pair bond between a male and female starts on the breeding ground and ends when the young fledge. Only the female sits on the eggs and broods the chicks, but both male and female feed them. They walk through forest floor leaf litter, gleaning and probing for invertebrate food. When predators approach a territory, both males and females may utter alarm calls and give chase. If a predator approaches a female on the nest, she sits tight until the last moment, then tries to lead the predator away by feigning injury. By day 8, the chicks leave the nest one at a time, with several hours between the first and last. As they run and hop away from the nest, the parents split the brood. The male keeps his young within the territory, and the female leads hers to an adjacent area. Females feeding young in neighboring territories are not harassed. The chicks need several more days to begin to fly, and don't become independent until around day 30. Immature Ovenbirds spend time feeding and "playfully chasing" other immature birds, who may or may not be from the same brood. They remain on the breeding grounds until after adult males and females have started their separate migrations in the fall, then they too set off. Ovenbirds seem largely solitary on the winter grounds.Back to top
Ovenbirds are numerous and their populations were stable or slightly increased overall between 1966 and 2014, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 22 million with 66% spending some part of the year in the U.S., 48% in Mexico, and 66% breeding in Canada. The species rates a 9 out of 20 on the Continental Concern Score. Ovenbird is not on the 2014 State of the Birds Watch List. These birds are sensitive to forest fragmentation and to disruption by industrial noise, forest road-building, and logging. Their ability to establish territories and breed successfully depends on the continued existence of large, undisturbed mature broadleaf and mixed forests. When Dutch elm disease spread through Minnesota forests, dying trees let more light filter to the forest floor and increased vegetation there; Ovenbird numbers declined. Forest fragmentation also increases Ovenbirds’ vulnerability to nest parasitism by Brown-headed Cowbirds. Ovenbirds do not recognize cowbirds or their eggs as intruders. Ovenbird eggs are eaten by snakes, Blue Jays, and Brown-headed Cowbirds. Red squirrels, eastern gray squirrels, raccoons, skunks, and weasels all take Ovenbird eggs and young. At least one study points to chipmunks as prime predators of the young. Barred Owls and Broad-winged Hawks prey on young and adult Ovenbirds alike. Ovenbirds migrate with storm fronts on their spring and fall migration routes. Large numbers are sometimes killed as they collide with towers and tall buildings along the paths of these fronts.Back to top
Lutmerding, J. A. and A. S. Love. Longevity records of North American birds. Version 2015.2. Patuxent Wildlife Research Center, Bird Banding Laboratory 2015.
North American Bird Conservation Initiative. (2014). The State of the Birds 2014 Report. US Department of Interior, Washington, DC, USA.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Porneluzi, Paul, M. A. Van Horn and Therese M. Donovan. (2011). Ovenbird (Seiurus aurocapilla), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Sauer, J. R., J. E. Hines, J. E. Fallon, K. L. Pardieck, Jr. Ziolkowski, D. J. and W. A. Link. The North American Breeding Bird Survey, results and analysis 1966-2013 (Version 1.30.15). USGS Patuxtent Wildlife Research Center (2014b). Available from http://www.mbr-pwrc.usgs.gov/bbs/.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, USA.
Stephenson, T. and S. Whittle (2013). The Warbler Guide. Princeton University Press, New Jersey, USA.