occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Breeding

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Breeding range extends from Alaska south through western Canada to U.S. Pacific Northwest and inland through parts of Idaho, Montana, and Wyoming (Stiles and Skutch 1989) Southern range extends west into the Cascades and interior ranges of Oregon and Washington, excluding the Central Basin (Wright et al. 1998). During the northern winter the species occurs in two distinct geographic areas: southwest British Columbia south along Pacific Coast to northern Baja California; and from southeastern Arizona and southwestern Texas through northwestern Mexico, south to highlands of Central America (Stiles and Skutch 1989, Wright et al. 1998).

Length: 13 cm

Weight: 9 grams

• Terrestrial

Comments: Tall coniferous and mixed coniferous-deciduous forest; in migration and winter, also humid forest, pine-oak association, open woodland, second growth, and scrub, primarily in montane situations (AOU 1983). Winters in higher elevation humid forests, including pine-oak and cloud forest; also in highlands in disturbed forest, edges, and clearings (Stiles and Skutch 1989). Few nests have been found. Appears to prefer conifers; may nest 2.7-4.5 m above ground, maybe higher (Terres 1980).

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Migrates through northern Mexico, including Baja California, and east to western Veracruz. Many arrive in nesting areas in Pacific Northwest in April-May (Bent 1953). Arrives in southern wintering range late September, departs by early April (Stiles and Skutch 1989).

Comments: Feeds mostly on insects (e.g. weevils, bugs, leafhoppers, caterpillars, etc.) and spiders. Winter: gleans small insects and caterpillars in foliage at all heights, occasionally hovers and plucks them from undersides of leaves; hawks flying insects (Stiles and Skutch 1989).

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: This species is represented by a large number of occurrences.

>1,000,000 individuals

Comments: Global population estimate is 12,000,000 birds (Rich et al. 2004). This species is most abundant on North American Breeding Bird Survey (BBS) routes in Washington [6.03 birds per route (bpr)], British Columbia (7.62 bpr), Idaho (7.41bpr), and Montana (5.41 bpr; Sauer et al. 2005). Less than 2 bpr were detected in Alberta and the Yukon. By physiographic strata, abundance was highest in the North Pacific Rainforest, the Cascades, and the central Rockies (Sauer et al. 2005).

Clutch size usually is 3-5.

Canada

Rounded National Status Rank: N5B - Secure

United States

Rounded National Status Rank: N5B,NNRN : N5B: Secure - Breeding, NNRN: Unranked - Nonbreeding

Rounded Global Status Rank: G5 - Secure

Reasons: Widespread in western North America, numerous, secure.

Comments: The largest and most imminent threat is habitat loss on both wintering and breeding grounds (Reed 1991). This species is considered to be one of the long-distance migrants most likely to be negatively affected by alteration of tropical forest habitats because of its predominant use of mature coniferous and pine-oak forest habitats in Mexico and Central America (Vidal-Rodriquez 1992, Petit et al. 1995). These preferred montane habitats are undergoing rapid conversion to pasture land, corn and coffee plantations, and residential development (Wright et al. 1998).

Breeding populations may be susceptible to traditional timber-harvesting practices such as clear-cut logging and even-aged management (Wright et al. 1998). These methods typically result in the loss of habitat features that Townsend's are known to select (Spindler and Kessel 1980, Mannan and Meslow 1984, BPIF 1999). Timber harvest-associated habitat fragmentation increases exposure to edge-related predators and parasites, and it could potentially reduce breeding densities (Gates and Gysel 1978, Brittingham and Temple 1983, Andren and Angelstam 1988).

Predation and brood parasitism by brown-headed cowbirds are not known to pose significant threats.

Biological Research Needs: Research needs include the following: Determine vulnerability of wintering birds to losses of mature forest in montane regions of Mexico and Central America (Wright et al. 1998). Study sensitivity of species to wintering habitat changes related to site fidelity, territoriality, and age- and sex-based dominance hierarchies (Rappole et al. 1983, Greenberg et al. 1993). Examine how increases in forest edge and reductions in contiguous forests affect this species (Wright et al. 1998). Identify the demographic transitions most important in determining population growth (Hayward and McDonald 1997). Examine the ecological relationship between Townsend's and Hermit Warblers in areas where they hybridize (Wright et al. 1998).

Global Protection: Very many (>40) occurrences appropriately protected and managed

Comments: Many occurrences are in national and state parks, wildlife refgues, wilderness areas, and other protected areas.

Comments: This species constitutes a superspecies with D. occidentalis, D. virens, and D. chrysoparia (AOU 1998). It is a sister species of D. occidentalis and hybridizes with occidentalis commonly where their ranges meet (AOU 1998, Rohwer and Wood 1998, Sibley 2001). The hybrid zone between the two species is narrow and moving, with D. townsendi replacing D. occidentalis (Rohwer and Wood 1998, Pearson and Rohwer 1998, Pearson and Manuwal 2000). Several instances of hybridization between Townsend's warbler and black-throated gray warbler (D. nigrescens) also have been reported (Wright et al. 1998).

No subspecies are currently recognized. Although considered monotypic, morphological differences suggest two distinct subspecies (Grinnell 1905, Morrison 1983). The population that winters in Oregon and California can be separated from the population wintering in Mexico and Central America by wing length; although these populations formally satisfy the designation as subspecies, they have not been formally designated as such (Morrison 1983, Pogson et al. 1997). Grinnell (1905) found that the population wintering along the Pacific Coast and breeding in Southeast Alaska and coastal British Columbia had shorter wing chords than birds wintering from northern Mexico to Costa Rica and breeding in the interior western United States. Morrison (1983) found a similar pattern, but he grouped specimens from Southeast Alaska with longer-winged birds wintering south of the United States.