Townsend's Warbler

                                            Townsend's Warbler   [Jim Carroll Photo]

A Townsend's Warbler (Setophaga townsendi) has recently caused much excitement among New Brunswick birders with its discovery at Waterfowl Lane, Sackville in late December.  It stayed into early January allowing many interested birders to see and photograph it.  Being a western warbler species, we do not usually get to see it.  The species has been seen twice before in the province, both in 2005.  One appeared in Fundy National Park from November 4-11 and one at Quispamsis from November 27 to December 11.  I was fortunate to see the one at Fundy National Park on November 5.  It was on a steep hillside along the road just past the Welcome Centre feeding actively in bushes. 

Townsend's Warbler  [Marbeth Wilson Photo]

The Townsend's Warbler is a western North American warbler species.  It is fairly common in the coniferous forests of the Pacific Northwest.  It breeds from Washington State and Oregon north to southern Alaska and Yukon Territory and east to southern Alberta.  It is a medium-to-long distance migrant and winters normally in the extreme western parts of Washington State, Oregon and California and inland areas of central Mexico.  This species prefers coniferous forest habitats for most of the year but can be found in lowlands in summer. 

The Townsend's Warbler was first described in 1837 by John Kirk Townsend, an American naturalist.  It was first called Sylvia townsendi but due to changes in taxonomy it was renamed, Setophaga.  It is from John Townsend that it gets its name.  

The Townsend's Warbler much prefers the tops of the large conifers of the west.  For that reason it can be difficult to see.  It finds lots of its usual diet of insects and spiders there.  As described by Taylor and Shaw (1927):  "On entering the great forest of the Pacific Northwest with its solitude, the deep-shaded grandeur of its brown-barked pillars and its stillness, one can almost imagine himself in a different world.  Incessantly repeated apparently from the very crowns of the trees, comes the song of the Townsend (sic) warbler, denizen of upper foliage strata."

                                        Townsend's Warbler  [Rosemonde Duguay Photo]

The Townsend's Warbler is a boldly patterned warbler.  It is closely related to the Black-throated Green Warbler which is common in New Brunswick.  It is the same size as this warbler (13 cm)  but differs in pattern.  In general, the Townsend's Warbler has dark cheek patches (auriculars)  surrounded by yellow, yellow on the breast, extensive white on the outer tail feathers, and two bold white wing bars.  The male shows a black cheek patch surrounded by yellow with a yellow crescent below the eye.  It has a black crown and an olive-green streaked back.  It shows a bold black chin and throat and broad stripes on its sides.  The belly and undertail coverts are white.  The adult female is more subdued with an olive-green crown and cheek patches, a yellow chin and throat with a bit of black showing, and the side streaks are narrow.  The plumages fade somewhat in winter plumage.  Immature birds are similar to females.  

The Townsend's Warbler will hybridize with the Hermit Warbler and the Black-throated Green Warbler where their ranges overlap.  Although there is some regularity in the plumage of these hybrids it would be left to the experts to identify these individuals.

                                            Townsend's Warbler  [Jim Carroll Photo]

The photos above show the olive green auricular, yellow breast, side streaking, yellow crescent under the eye, white vent and outer tail feathers.  The side streaking is fairly bold so this may be a winter-plumaged adult male.

Here in New Brunswick the Townsend's Warbler must be differentiated from the Black-throated Green Warbler.  The Black-throated Green Warbler does not have the dark auriculars nor the yellow throat and breast.  It also has a yellow vent and not the white vent of the Townsend's Warbler.  The immature female Blackburnian Warbler is also similar but shows less green and more streaking on the back.  It shows no black or streaking on the throat.   In the west the Townsend's Warbler must be separated from the Hermit Warbler where the Townsend's Warbler has streaked flanks and well defined cheek patches.

The Townsend's Warbler places its nest on top of a branch of a conifer tree in a well concealed location.  It is a shallow nest, made of grass and lined with moss.  Four to 5 brown-speckled white eggs are laid and incubated for 12 days by the female.

The Townsend's Warbler begins to sing before it leaves its winter range.  It must love to sing because it has been described as 'singing to itself' as it moves around gleaning insects from the foliage.  The voice has been described as variable and buzzy and is represented as weazy weazy weazy dzee.  Its call note is a sharp tsik. I imagine the call of this species is very familiar to the people of the west who enjoy hiking in the forest.  The voice changes somewhat later in the season.  In the west one would have to distinguish its voice from that of the Black-throated Gray Warbler.

We are blessed to have rare avian species show up periodically in New Brunswick.  It is interesting and broadens the knowledge of our naturalists.

                                                Townsend's Warbler  [Jim Carroll Photo]