Measurements
Both Sexes
- Length
- 7.5–8.3 in
19–21 cm - Wingspan
- 11.8–13.4 in
30–34 cm - Weight
- 1.4–1.8 oz
40–50 g
Other Names
- Grive des bois (French)
- Zorzal del Bosque, Zorzal maculado, Zorzal pechimanchado, Tordo maculado (Spanish)
Cool Facts
- Declines in Wood Thrush populations have been linked to acid rain and forest fragmentation by studies conducted by the Cornell Lab of Ornithology's Bird Population Studies, using data from the Birds in Forested Landscapes project. For more information about the study and its findings, go here.
- The Brown-headed Cowbird frequently parasitizes the nests of Wood Thrushes. In some parts of the Midwest all of the Wood Thrush nests contain at least one cowbird egg, and some may contain up to eight
- Thrushes have a complicated syrinx (song box) that allows them to sing two notes at the same time and harmonize with their own voice.
- Wood Thrushes may raise more than one brood each season. When the first brood fledges, both parents feed all the young, but when the last brood fledges, they divide the work, each one caring for half the brood.
- A Wood Thrush often returns to the same breeding territory in successive years. It also may return to the same wintering area each year.
- Has been observed "anting." Anting occurs when a bird picks up a single ant or group of ants and rubs them on its feathers. The purpose of this behavior is not well understood. It is thought that birds may be able to acquire defensive secretions from the ants possibly used for some medicinal purpose. Also may be a supplement to the bird's own preen oil.
Habitat
Forest
Breeds in the interior and edges of deciduous and mixed forests, generally in cool, moist sites, often near water.Requires moderate to dense understory and shrub density with a lot of shade, moist soil, and decaying leaf litter. Shows much variation in habitat use, from mature deciduous forests in the Southeast, to shrubby second-growth forests and suburban parks in the Northeast to riparian habitats in the Great Plains. Winters in lowland tropical forests. Most numerous in interior understory of tropical primary, closed-canopy, semi-evergreen, broad-leaved, and mixed palm forests at 50-1000 m elevation.
Food
Insects
Eats beetles, ants, moths, caterpillars, millipedes, and isopods. In the late summer and fall eats more fruit: spicebush, foxgrape, blueberry, holly, elderberry, Virginia creeper, pokeweed, dogwood, black cherry, and black gum.
Nesting
Nesting Facts
- Clutch Size
- 3–4 eggs
- Egg Description
- Smooth, blue-green, with no markings.
- Condition at Hatching
- Naked with small patches of down.
Nest Description
Open cup of leaves and grasses lined with mud, placed on lower limbs of tree or shrub.Nest site: On the lower limbs of a tree or shrub, hidden among leaves in a shady area. Generally near or against the trunk. Also found in a crotch or fork supported by small branches. May be anchored to a branch with mud.
Height: Usually 10-13 ft (3-4 m) above ground; 2-70 ft (0.5-21 m) possible.
Nest: Nest is made of dead leaves, dried grasses, bark, and moss, with a middle layer of mud. Often contains pieces of white paper or cloth. The cup is molded by the female as she packs the base and sides with her body during the building process. The cup is lined with fine rootlets. Female builds the nest in approximately three to six days.
Nest Placement
Tree
Behavior
Ground Forager
The male arrives and establishes a territory several days before the female arrives on the breeding ground. The female leads silent circular flights about 3-6 ft (1-1.8 m) from the ground, with the male chasing the female. Generally six or more flights take place in succession. In between each flight the pair perches together and may feed one another.Sings from an exposed perch, usually in the lower canopy or mid-story. Often flushes from the forest floor. When performing an agonistic display (a behavior used to threaten another bird), there may be brief physical contact between males with feet or bill if defending a territory or nest. Other aggressive displays are fairly passive: wing and tail flicks, raised crests, and puffing up of breast feathers. Observed to be aggressive toward robins, Veeries, Blue Jays, and other species.Forages by gleaning and probing in the leaf litter on the forest floor. Always forages under the forest canopy, hops and then pauses to scatter leaves to find prey. Sometimes hawks or hovers to glean insects or fruit from vegetation above the ground. Young are fed small insects and some fruit.
Conservation
Least Concern
Even though it is one of the most common species of Eastern forests, the Wood Thrush is of high conservation concern because of steady, long-term population declines, nearly throughout its range. This species has declined 43% overall since 1966. This species seems to be dependent on large tracts of mature forest in some parts of its range, but is tolerant of disturbance in other areas. In winter, it is highly vulnerable to tropical deforestation in the lowlands of Central America. Understanding the precise breeding habitat requirements of this species, and how they vary geographically, will be important for reversing population declines and maintaining future populations. Listed on the Audubon Watchlist
Credits
- Roth, R. R., M. S. Johnson, and T. J. Underwood. 1996. Wood Thrush (Hylocichla mustelina). In The Birds of North America, No. 246 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
- Evans, W. E., and M. O'Brian. Flight Calls of the Birds of Eastern North America. CD, self-published.