The Magnolia Warbler breeds in moist coniferous and mixed forest from Yukon and British Columbia to Newfoundland and the Maritimes, mostly in Canada but also in the upper Midwest, New England, and the Appalachians. It migrates east of the Great Plains, crossing the Gulf of Mexico to and from its wintering grounds in southeastern Mexico and Central America, but is also one of the more common vagrant “eastern” warblers seen in the western United States. Oregon and Idaho both have more than 20 records. Washington has 12 accepted records, seven east of the Cascades and five from westside coastal lowlands. Nine are from fall (September–October), while two occurred in late May at Ione (Pend Oreille County) and near Dixie (Walla Walla County). The other record was of a male singing on territory near Twisp (Okanogan County) for nearly a month, 8 June–4 July 1996.
In fall, when it is most likely to be seen in Washington, this species has greenish upperparts, a gray head with a prominent white eye-ring, two white wingbars, yellow underparts from chin to belly, streaked sides (sometimes weakly), and white undertail coverts. Key field marks are the yellow rump, white underside of the front half of the tail, and wide white band visible on the spread tail. There is considerable variation in plumage by age, sex, and season. In particular, breeding birds are much more strongly patterned: consult a good field guide for details.
Members of this diverse group make up more than half of the bird species worldwide. Most are small. However their brains are relatively large and their learning abilities are greater than those of most other birds. Passerine birds are divided into two suborders, the suboscines and the oscines. Oscines are capable of more complex song, and are considered the true songbirds. In Washington, the tyrant flycatchers are the only suboscines; the remaining 27 families are oscines.
This large group of small, brightly colored songbirds is a favorite of many birdwatchers. Wood-warblers, usually called “warblers” for short by Americans, are strictly a New World family. Most of the North American members of this group are migratory, returning in the winter to the tropics where the family originated. Warblers that nest in the understory tend to have pink legs and feet, while those that inhabit the treetops usually have black legs and feet. North American males are typically brightly colored, many with patches of yellow. Most North American warblers do not molt into a drab fall/winter plumage; the challenge posed to those trying to identify warblers in the fall results from looking at mostly juvenile birds. Their songs are generally dry, unmusical, often complex whistles (“warbles”). Warblers that live high in the treetops generally have higher-pitched songs than those that live in the understory. Warblers eat insects gleaned from foliage or captured in the air. Many supplement their insect diet with some seeds and fruit, primarily in fall and winter, and some also eat nectar. Most are monogamous. The female usually builds the nest and incubates four to five eggs for up to two weeks. Both members of the pair feed the young.