Bird GuideWood WarblersMourning Warbler

At a Glance

Often elusive and hard to see well, the Mourning Warbler sings a repetitious chant from thickets and raspberry tangles in the north woods. This bird lives near the ground at all seasons, foraging in low brush and in the forest understory even during migration; it tends to be solitary, not readily joining flocks of other warblers. It got its name because the extensive black throat patch of the male suggested to pioneer naturalists that the bird was dressed in mourning.
Category
Perching Birds, Wood Warblers
IUCN Status
Least Concern
Habitat
Forests and Woodlands, Shrublands, Savannas, and Thickets
Region
California, Eastern Canada, Florida, Great Lakes, Mid Atlantic, New England, Plains, Southeast, Texas, Western Canada
Behavior
Direct Flight, Flitter
Population
14.000.000

Range & Identification

Migration & Range Maps

In spring, apparently moves north overland through Mexico and Texas, rather than crossing the Gulf of Mexico like many other migrants; evidently retraces same route in fall. Migrates relatively late in spring and early in fall.

Description

5 1/2" (14 cm). Olive above, yellow below, with gray hood. Adult male has veiled black on throat; female paler, may show narrow eye-ring. Some fall immatures suggest female Common Yellowthroat, but show hint of hood, more evenly yellow belly.
Size
About the size of a Sparrow
Color
Black, Gray, Green, Yellow
Wing Shape
Rounded
Tail Shape
Rounded, Square-tipped

Songs and Calls

Loud, ringing, musical song, teedle-teedle, turtle-turtle, the last pair of notes lower.
Call Pattern
Falling, Flat
Call Type
Chirp/Chip, Trill

Habitat

Clearings, thickets, slashings, undergrowth. Breeds in brushy northern habitats, including dense shrubbery in old deciduous woods clearings, brushy cut-over lands, lowland thickets of raspberry and blackberry tangles, or bog and marsh edges; often in temporary habitats, growing up after fires or clearcuts. In winter in the tropics, lives in low, dense thickets and overgrown fields in lowlands and foothills.

Behavior

Eggs

3-4, sometimes 5. Creamy white with brown spots or blotches. Incubated by female only, about 12 days. Male feeds female on nest during incubation.

Young

Both parents feed nestlings. Young leave the nest after 7-9 days. Care of fledglings may continue for another 4 weeks or more.

Feeding Behavior

During the breeding season, forages primarily in shrubs within a few feet of the ground; hops while feeding on ground. Sometimes makes short flights to catch flying insects. Generally feeds alone rather than joining flocks.

Diet

Probably mostly insects. Details of the diet are poorly known, but has been seen foraging for caterpillars, beetles, and other insects; also eats spiders. In winter in the tropics, sometimes feeds on the protein bodies from the leaf-bases of young cecropia trees.

Nesting

Details of the breeding behavior are not well known. Male sings to defend nesting territory; during territorial boundary encounters with rival males, he may bob violently, flip wings outward, and fan his tail. Nest: Usually placed on ground next to shrub at base of weeds in raspberry or blackberry briars, or among fern, goldenrod, or grass tussocks. Also sometimes in bush within a couple of feet of the ground. Nest (probably built by both sexes) is an open, bulky cup made of leaves, with a core of weeds and coarse grasses, lined with fine grass and hair.

Climate Vulnerability

Conservation Status

Current numbers probably stable. Because it inhabits shrubby second growth in both summer and winter, not as vulnerable as some warblers to loss of habitat.

Climate Map

Audubon’s scientists have used 140 million bird observations and sophisticated climate models to project how climate change will affect the range of the Mourning Warbler. Learn even more in our Audubon’s Survival By Degrees project.

Climate Threats Facing the Mourning Warbler

Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.