Grace's Warbler

Grace's Warbler (Setophaga graciae) is a small, attractive songbird native to the montane pine forests of the southwestern United States and Mexico. First described in 1865 by naturalist Spencer Fullerton Baird, he named this elegant warbler after his sister, Grace Darling Baird. Unlike many other wood-warblers that forage close to the forest floor or in low brush, Grace's Warbler is a high-canopy specialist, making it a thrilling and sometimes challenging find for birdwatchers. Its soft gray, bright yellow, and clean white nesting plumage provides excellent camouflage among the needles of mature ponderosa pines, where it spends the majority of its life.

Identifying a Grace's Warbler requires looking toward the treetops. Key field marks include:

• Throat and Breast: A brilliant, solid yellow throat and upper breast that contrasts sharply with white underparts.
• Face Pattern: A distinct yellow supraloral stripe (the line in front of the eye), which transitions to white behind the eye to form a broken eyebrow. The rest of the face and ear patch (auriculars) are soft gray.
• Upperparts: The back, nape, and crown are a uniform blue-gray, with fine black streaking on the crown and back.
• Wings and Tail: Blue-gray wings featuring two prominent white wing bars. Outer tail feathers show conspicuous white patches when fanned.
• Flanks: The flanks are clean white with bold, black streaks running down the sides.

Similar Species

• Yellow-throated Warbler (Setophaga dominica): Though plumage is superficially similar, the Yellow-throated Warbler has a bold black-and-white face pattern, a classic black "whisker" mark, a fully white eyebrow, and is larger. Its range is also primarily eastern, whereas Grace's is southwestern.
• Hermit Warbler (Setophaga occidentalis): Possesses a completely yellow face and head, a black throat (on males), and lacks the clean gray back and restricted yellow throat-patch of Grace's.
• Audubon's (Yellow-rumped) Warbler (Setophaga coronata auduboni): Shares a yellow throat but features a yellow rump, yellow side patches, a dark chest band, and lacks the clean white-and-gray facial coloration of Grace's.

Grace's Warblers are high-altitude pine specialists. Their distribution is closely tied to mature pine forests, particularly those dominated by Ponderosa Pine (Pinus ponderosa), Jeffrey Pine, and mixed pine-oak woodlands, typically at elevations between 5,000 and 9,000 feet (1,500 to 2,700 meters).

Range and Migration

During the breeding season (May to August), Grace's Warbler can be found in the southwestern United States, covering parts of Arizona, New Mexico, southern Utah, southwestern Colorado, Nevada, and extreme western Texas. They are migratory, traveling south to spend the winter in the pine-oak forests of western and southern Mexico, Guatemala, Honduras, and Nicaragua. Resident populations exist year-round in portions of southern Mexico and Central America.

Feeding

Grace's Warbler is almost entirely insectivorous, feeding on caterpillars, beetles, spiders, and leaf-hoppers. They are active, acrobatic foragers that creep along horizontal branches and needle clusters high in the canopy to glean prey. On occasion, they will perform short aerial sallies to catch insects mid-air.

Voice & Call

Because they dwell so high in the trees, they are often heard before they are seen. The male's song is a rapid, accelerating, and ascending series of dry, musical chips (chi-chi-chi-chi-chichichi-chrrr), lasting about 1 to 2 seconds. It bears a passing resemblance to the song of a Chipping Sparrow or a Yellow-rumped Warbler but is sweeter, louder, and faster at the finish. The call is an unremarkable, soft, flat tsip.

Nesting

Nest building occurs high in the canopy, usually 20 to 60 feet (6 to 18 meters) above the ground, making nests extremely difficult to locate. The cup-shaped nest is constructed primarily by the female using pine needles, oak catkins, bark fibers, and spiderwebs, lined inside with fine grass, animal hair, and feathers. A typical clutch consists of 3 to 4 creamy-white eggs decorated with fine brown spots. Both parents assist in feeding the nestlings.