The wood thrush ( Hylocichla mustelina) is a North American passerine bird in the family Turdidae. It is the only species placed in the genus Hylocichla. This reclusive bird has cinnamon brown upperparts that serve as good camouflage as it forages for leaf-litter invertebrates deep in the forest. It pops upright frequently to peer about, revealing a boldly spotted white breast. The male and female are similar in appearance. Though still numerous, its rapidly declining numbers may be due in part to cowbird nest parasitism at the edges of fragmenting habitat and to acid rain's depletion of its invertebrate prey.
Identification and Habitat
You'll likely hear the Wood Thrush before you see it. The male sings his haunting, flute-like ee-oh-lay song from the lower canopy or midstory of deciduous or mixed eastern forests. To see Wood Thrushes, look for them foraging quietly on the forest floor and digging through leaf litter.
Wood Thrushes breed throughout mature deciduous and mixed forests in eastern North America, most commonly those with American beech, sweet gum, red maple, black gum, eastern hemlock, flowering dogwood, American hornbeam, oaks, or pines. They nest somewhat less successfully in fragmented forests and even suburban parks where there are enough large trees for a territory. Ideal habitat includes trees over 50 feet tall, a moderate understory of saplings and shrubs, an open floor with moist soil and decaying leaf litter, and water nearby. Favored understory species include southern arrowwood, smooth blackhaw, spicebush, coast pepperbush, rhododendron, and blueberry. In their winter range, they are most abundant in the interior of mature, shady, broad-leaved and palm tropical forests in lowlands. As in their temperate range, they will also inhabit forest edges and the denser understory of second-growth forests.
The adult wood thrush is 18 to 21.5 cm (7.1 to 8.5 in) long, with a wingspan of 30 to 40 cm (12 to 16 in) and a body mass of 48 to 72 g (1.7 to 2.5 oz). The crown, nape, and upper back are cinnamon-brown, while the back wings, and tail are a slightly duller brown. The breast and belly are white with large dark brown spots on the breast, sides, and flanks. It has white eye rings and pink legs. The juvenile looks similar to adults, but has additional spots on the back, neck, and wing coverts.
Food Preferences and Foraging Behavior
Wood Thrushes feed mostly on leaf-litter invertebrates and fruits from shrubs. The wood thrush is an omnivore, and feeds preferentially on soil invertebrates and larvae, but will also eat fruits.
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The Wood Thrush is usually one of the first song birds to be heard in the woods in the morning and among the last in the evening. To establish a territory, the male sings his evocative song from an exposed perch in the understory or lower canopy.
Their summer diet is predominantly invertebrates, including adult beetles and flies, caterpillars, spiders, millipedes, woodlice, and ants. Insects, snails, and salamanders found in trees are occasional prey.
Fruits like spicebush, fox grape, blueberry, holly, elderberry, jack-in-the-pulpit, Virginia creeper, pokeweed, dogwood, black cherry, and black gum make up most of the rest of their diet. Parents feed chicks soft invertebrates and pre-softened fruits.
The Wood Thrush diet consists of both insects and fruits. Insects provide birds with more crude protein (31-80 %) than fruit (e.g. cherry: 2%). Thus, Wood Thrushes eat little fruit material during spring (5% of diet) and summer months (35 %), but fruits comprise 77 % of the diet during the fall when insects are less available.
In late summer and fall, after breeding season, Wood Thrushes shift their diet toward fruits (particularly fatty fruits) in preparation for the demands of migration. Fruits remain important on migration and in winter, though Wood Thrushes remain omnivorous, eating a wide variety of insects as well. After breeding and before migration, the wood thrush will switch from insects to fruits with high lipid levels.
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The wood thrush forages mainly on the forest floor, flipping leaves over with its bills to reveal insects. It can be observed hopping around in leaf litter and on semi-bare ground under the forest canopy.
Nestling Diet and Parental Care
Wood Thrush nestlings are fed largely on an insect diet and are not fed plant materials until they are well developed. The type of food and amount delivered to nestlings is determined by the energy content of the food delivered and the adults' foraging ability and time constraints. Both parents feed the nestlings.
Nesting Habits
The nest is usually in the lower branches of a sapling or shrub, where a fork provides good support and twigs or foliage provide shade and cover. The male may call attention to a spot by calling or by placing nest materials nearby, but the final decision is the female's.
The female begins nest building by laying down a platform of dead grass, leaves, stems, and sometimes paper or plastic. She weaves walls 2-6 inches high using the same materials, ending up with a cup that’s 4-6 inches across. She stamps the floor tight and uses the weight of her body to mold a 3-inch inner cup. Then she lines the cup with mud which she smoothes with her breast. She finally adds a covering of rootlets to bed the eggs. The process takes 3-6 days. A pair often raises two broods of youngsters per season, but may need 3 or 4 attempts to do so. A second nest after a successful first is often within 300 feet, but an unsuccessful nest may provoke a wider search for a new site.
Threats and Conservation Status
The 2025 State of the Birds report lists Wood Thrush as a Yellow Alert Tipping Point species, meaning that it has lost more than 50% of its population in the past 50 years but has relatively stable recent trends. According to the North American Breeding Bird Survey, this species declined by an estimated 1% per year between 1966 and 2023, resulting in a cumulative decline of 45% over that period. Partners in Flight estimates a global breeding population of 12 million individuals and rates the species 14 out of 20 on the Continental Concern Score.
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Wood Thrush is one of the most prominent examples of declining forest songbirds in North America. Some of the steepest population declines have been along the Atlantic Coast and in New England states where Wood Thrushes are most common. Habitat fragmentation on their breeding and wintering grounds is thought to be one reason for their decline. Fragmented habitats may have lower quality food choices or expose nests to predators such as raccoons, jays, crows, and domestic or feral cats, and to the Brown-headed Cowbird, which is a nest parasite. Wood Thrushes are also susceptible to the effects of acid rain, which can leach calcium from the soil, in turn robbing the birds of vital, calcium-rich invertebrate prey.
Habitat protection and restoration are key to wood thrush conservation. Efforts should focus on preserving and expanding large, contiguous tracts of mature, moist hardwood or mixed forests with a well-developed understory. Land conservation initiatives, such as conservation easements and protected areas, can help maintain critical breeding habitat. In areas where habitat fragmentation is unavoidable, targeted management strategies such as increasing native shrub cover and limiting human disturbance near nesting sites may improve reproductive success.
In regions where brown-headed cowbird parasitism is a significant issue, management may be considered. Promote responsible pet ownership that supports wildlife and pet health by keeping cats indoors and encouraging others to follow guidelines found at fishwildlife.org.
Bird collision mortalities can be minimized by making glass more visible to birds.