Townsend's Warbler

Dendroica townsendi

By Andy McCormick

  • Length          5 in
  • Wingspan      8 in 
  • Weight           0.31 oz
  • AOU Band code    TOWA

This boldly patterned warbler is a Pacific Northwest specialty that inhabits our coniferous forests. Townsend’s Warblers are a bright spot in the northwest’s gray winters and welcome visitors to the lowlands. They can occasionally be seen at suet feeders to the delight of backyard birders. This bird is part of a super-species known as the “virens (green) group” which is also comprised of Black-throated Green, Black-Throated Gray, Golden-cheeked, and Hermit Warblers.  All have a distinctive black throat and all but the Golden-cheeked have a green back for which the group is named. Townsend’s Warbler is characterized by a black cheek patch at the auriculars surrounded by yellow, yellow on the chest with black streaks on the sides, and white wing bars. Its closest relative the Hermit Warbler Dendroica occidentalis, with which it often hybridizes near the Oregon-Washington border, has no black on the face and a white chest.  

Dendroica ,tree dwelling, is the largest of the warbler genera and is from the Greek, dendron, tree, and oikos, house or dwelling.  The species townsendi is for John Kirk Townsend (1809-1851), an ornithologist from Philadelphia who studied birds in the west. Warbler is for the trills and quavers of the song (Holloway). 

In the breeding season Townsend’s Warbler prefers denser forests of grand fir, Douglas fir and Engelmann spruce.  It forages at the tops of conifers for caterpillars, beetles and leafhoppers and will also sally out for flying insects. Its nest is a shallow cup made of grass stems, mosses and cedar bark and is constructed on the end of a high branch. Because of the height of the nests the breeding habits of Townsend’s Warbler have been difficult to study. Typically 4-5 eggs are deposited in the nest by early June. It is estimated that incubation lasts about 12 days and the birds leave the nest in another 10 days (Kaufman). 

In spring Townsend’s Warblers begin arriving at higher altitudes in the northwest during April and settle on the breeding grounds in May. In fall Townsend’s Warblers migrate to lower altitudes and many winter in mixed woodlands close to Puget Sound and along the Pacific coast from British Columbia through California.  The majority migrate to Mexico and Central America. In the north it appears that the birds are expanding their breeding range northward into Alaska, which may be similar to other bird species as a result of generalized warming trends. Because of its preference for dense forests Townsend’s Warblers are vulnerable to forest fragmentation. International conservation efforts are needed to protect dense old-growth forests in the north and higher altitude forests in the wintering range (Wright). 

Many warblers are identified by sound and Townsend’s Warbler is no exception.  Its song is a buzzy weazy weazy weazy dzeee or alternatively a buzzy zi-zi-zi-zi-zi-zi, zwee, zwee. 

Photo by Mick Thompson

Photo by Mick Thompson

Wilson's Warbler

Cardellina pusilla

By Andy McCormick

  • Length          4.75 in
  • Wingspan      7 in 
  • Weight           0.27 oz
  • AOU Band code    WIWA

Wilson’s Warbler is often found along wooded streams, in low shrubs, willows and alders (Kaufman). It sings loudly and regularly and can lead a birder trying to see it on a frustrating chase through dense underbrush, but persistence will pay off with a view of this lovely bird. Its song is more of a descending chatter chi chi chi chi chi chet chet, than a song. 

The Wilson’s is bright yellow on the forehead, face, throat, chest, belly and undertail coverts. However, its tail is dark on both the upper and lower sides. Its back and wings are a yellowish olive separating it from other yellow warblers. A definitive field mark is the black cap on the male and grayer cap of the female, which also has more muted yellow plumage. Its beady black eye is prominent. 

Wilson’s Warbler is an early migrant in the west with northward movement beginning in March and peaking in Western Washington by mid-May (Ammon and Gilbert). Fall migration begins in August and most of these warblers winter south of the United States usually in forest edge habitat, riparian areas and thorn brush areas, habitat that is similar to its northern breeding areas (Ammon and Gilbert). Pacific Coast Wilson’s Warblers typically migrate around the western coast of Central America.

As a result of recent genetic research Wilson’s Warbler has been placed in the genus Cardellina, diminutive for the Latin carduelis, goldfinch, or a kind of finch. The species name pusilla is Latin for very small or tiny (Holloway). It is formerly in the genus Wilsonia, named after the famed ornithologist Alexander Wilson, who first named this bird the Green Black-capt Flycatcher (Mearns and Mearns). It moves sprightly; flipping its tail as it forages in low shrubs showing great agility as it forages for insects of all kinds. 

Wilson’s Warblers are m ore numerous in the West, and some of the highest breeding densities of the Wilson’s occur in Western Washington. This warbler most often nests on the ground or up to three feet above ground in forest edge habitat. It does not like to be under forest canopy. The female builds an open-cup nest of dried leaves, grasses and moss. Along the Pacific coast the subspecies C. p. chryseola usually deposits two to four eggs in the nest. At higher elevations of the Rocky Mountains the subspecies C. p. pileolata deposits more eggs, sometimes as many as six or seven. Incubation takes less than two weeks. The young are fed by both parents and leave the nest within two more weeks (Kaufman). Some pairs will have a second brood.

The population of Wilson’s Warblers remains strong although there have been declines throughout Western North America. “Degradation and loss of primary breeding habitat, western riparian woodlands, are likely among the leading causes of declines… Protecting and restoring native riparian habitat within the breeding range will likely play a key role in long-term conservation of this species” (Ammon and Gilbert). 

Photo by Mick Thompson

Photo by Mick Thompson

Hermit Warbler

Setophaga occidentalis

By Andy McCormick

  • Length          5 in
  • Wingspan      8 in 
  • Weight           0.32 oz
  • AOU Band code    HEWA

The Hermit Warbler is considered a specialist in living in the canopy of 200 foot tall conifers. In western Washington it populates Douglas firs, western hemlocks, and western red cedars. It winters in pine-oak forests in Mexico and in California it enjoys Jeffrey, pondersosa, and lodgepole pines. It forages so high that it is often heard long before it is seen. 
High Wire Specialist

The Hermit is not really solitary. It is just difficult to find high in the canopy. It begins foraging near the trunk and works its way toward the end of a branch, and then flies into a trunk to start on another branch, but not always in the same tree. It uses a variety of techniques employed by other canopy birds. It sometimes hover-gleans as Golden-crowned Kinglets do, as they pick insects from leaves and twigs while staying steady in flight. It will also hang onto branches as chickadees do. Using a third method similar to flycatchers, but less often than other means, it will sally out to hawk insects in the air. The Hermit Warbler’s diet consists almost entirely of insects. 

The Hermit Warbler migrates strictly along the Pacific Flyway. It is an early migrant arriving on the breeding grounds in early May. In the fall it leaves the breeding area earlier than other warblers, typically heading south in early August or even late July. It follows the forests until some birds settle in California and others winter in the forests of western Mexico.
Warbler Sisters

The Hermit Warbler is a sister species of Townsend’s Warbler (S. townsendi) and both are part of the virens superspecies which also includes the Black-throated Gray, Golden-cheeked, and Black-throated Green Warblers (Dunn and Garrett). The Hermit and Townsend’s Warblers enjoy similar habitat and hybridize regularly in areas where they overlap in Southwest Washington and on the east side of the Olympic Peninsula. Recent studies find that the range of the hybridization zone is moving south, which may indicate that Townsend’s Warbler is competitively superior to the Hermit Warbler (Pearson). Hybrids will generally keep the yellow face of the Hermit Warbler, and show yellow on the breast similar to Townsend’s Warbler. 

The Hermit is in the genus Setophaga, moth eater, from the Greek setos, moth, and phagein, eat, with the species name occidentalis, of the west, based on its habitat in western Washington, Oregon, and California. Difficulty in finding this bird led to the name Hermit. However, this species is not solitary in its habits (Holloway), and it will be found in mixed flocks in the early spring. 

Made in Washington
The Hermit Warbler breeds in Pacific Northwest coniferous forests. The female builds the nest on a horizontal branch out from the trunk. The nest is constructed as a deep cup built of weed stalks, pine needles, twigs, lichen, and moss and lined with softer materials such as soft bark and cobwebs. Usually four eggs are deposited. The timing of incubation and first flight are not well-documented. The young may leave the nest about 10 days after hatching (Kaufman). 

The Hermit Warbler is vulnerable to changes in forests in both its breeding and wintering areas. It is considered “a habitat specialist, has a narrow geographic distribution, and does not have a large population” (Reed in Pearson). Forest practices that include longer rotations between harvests on private land, reduced forest edge by keeping forest stands intact, and high canopy closure “…would likely benefit breeding, wintering, and migrating populations” (Pearson).

Photo by Ollie Oliver

Photo by Ollie Oliver

Yellow-rumped Warbler

Setophaga coronata

By Andy McCormick

  • Length          5.5 in
  • Wingspan      9.25 in 
  • Weight           0.43 oz
  • AOU Band code    YRWA