In late summer and fall, when 13 of the 16 accepted Washington records have occurred, the Tennessee Warbler is a plain yellowish-green bird with a light eyebrow and a thin, dark line through the eye and can easily be confused with its close relative, the Orange-crowned Warbler—an abundant migrant and summer resident in the state. The most obvious differences are the Tennessee’s shorter tail and white or near-white undertail coverts that contrast with the grayish or greenish breast, and the absence of the Orange-crowned’s streaking on the underparts. The song, although rarely heard in Washington, is also quite different. Tennessee Warblers in breeding plumage are noticeably grayer (less greenish) than fall birds. Confusion with vireos is also possible, but note the warbler’s thin, sharply pointed bill.
The breeding range of the Tennessee Warbler extends from coast to coast in the forests of Canada, barely grazing the U.S. in Minnesota and New England. The wintering grounds extend from southern Mexico through Central America to Colombia. Although this warbler nests in British Columbia and Alberta south almost to the Montana border, its migration route lies east of the Continental Divide. Vagrant Tennessee Warblers occur with some frequency in the West, predominantly in fall. Idaho has about 30 records and the species is annual in Oregon, where it is no longer on the state review list. Ten of Washington’s records are from west of the Cascades and six from east. One long-staying bird was present into January at Satsop (Grays Harbor County).
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.
Blue-winged WarblerVermivora pinus
Golden-winged WarblerVermivora chrysoptera
Tennessee WarblerVermivora peregrina
Orange-crowned WarblerVermivora celata
Nashville WarblerVermivora ruficapilla
Northern ParulaParula americana
Yellow WarblerDendroica petechia
Chestnut-sided WarblerDendroica pensylvanica
Magnolia WarblerDendroica magnolia
Cape May WarblerDendroica tigrina
Black-throated Blue WarblerDendroica caerulescens
Yellow-rumped WarblerDendroica coronata
Black-throated Gray WarblerDendroica nigrescens
Black-throated Green WarblerDendroica virens
Townsend's WarblerDendroica townsendi
Hermit WarblerDendroica occidentalis
Blackburnian WarblerDendroica fusca
Yellow-throated WarblerDendroica dominica
Prairie WarblerDendroica discolor
Palm WarblerDendroica palmarum
Bay-breasted WarblerDendroica castanea
Blackpoll WarblerDendroica striata
Black-and-white WarblerMniotilta varia
American RedstartSetophaga ruticilla
Prothonotary WarblerProtonotaria citrea
OvenbirdSeiurus aurocapilla
Northern WaterthrushSeiurus noveboracensis
Kentucky WarblerOporornis formosus
Mourning WarblerOporornis philadelphia
MacGillivray's WarblerOporornis tolmiei
Common YellowthroatGeothlypis trichas
Hooded WarblerWilsonia citrina
Wilson's WarblerWilsonia pusilla
Yellow-breasted ChatIcteria virens