Pacific Wren

The Pacific Wren has round appearance and short wings and tail. It has brown plumage overall.
On the upperwing, the coverts are rufous-brown with darker bars. Primaries and secondaries are brown with blackish bars. The short, stubby tail is chestnut-brown with dark bars.
On the underparts, the upper breast is pale brown, but belly and flanks are warmer brown with dark barring.
On the head, the face is brown and we can see a pale supercilium. Forehead, crown and nape are brown with fine darker bars. Chin and throat are pale brown.
The thin, pointed bill is pale brownish with paler base. The eyes are dark brown, with white crescent below the eye. Legs and feet are pale brown.
Male and female are similar.

The juvenile resembles adult, but it has unmarked colour on the upperparts, darker underparts with dark edges to feathers, and less distinct barring on flanks, vent and undertail-coverts.
On the head, both supercilium and post ocular stripe are indistinct.

SUBSPECIES AND RANGE:
Depending on the authors, the Pacific Wren has 7 to 14 subspecies which differ in size, coloration and plumage pattern.
It is found in Alaska, Canada and NW USA and on several islands such as Pribilof Islands and most of Aleutian Islands. It is also present in SW Oregon to C California, and interior of W USA, NW USA and SW Canada.
The birds breeding at high elevations in mountains perform altitudinal movements after breeding.

HABITAT:
The Pacific Wren frequents the forest floor in moist coniferous forests, and favours the habitats with fallen logs, woody debris, stumps and dead wood used for nesting. It can be found in stunted vegetation in Aleutian Islands.
It also frequents mature and old-growth forests, and areas associated with bogs, swamps, streams and lakes. But it also occurs in woodland far from water.
In Sierra Nevada range, the species is present from sea-level to 3,700 metres of elevation.
During winter, it frequents more open woodlands, deciduous riparian forests and logged areas, and parks and gardens with brush piles and tangles.

CALLS AND SONGS: SOUNDS BY XENO-CANTO
The Pacific Wren is known for its beautiful song and its large repertoire of sounds. The bird uses many notes in different arrangements.
The long, complex song is a series of ringing, tinkling trills of about six seconds, with harsh, staccato quality. The female is not known to sing.
From an observation, individual males produced an average of 21 song types over two mornings. The length of the song is closely related to the ambient noise.
The calls of this species include a sharp “timp” and “chek-chek” notes.

BEHAVIOUR IN THE WILD:
The Pacific Wren feeds mainly on insects of various species such as beetles, caterpillars, true bugs, flies and others. It also eats spiders, some millipedes and snails. Berries are consumed too, depending on the season.
It often forages in low, dense vegetation, and searches for invertebrates among foliage, on twigs or trunks and on the ground.
It forages on decaying logs and among the roots of fallen trees, around the trunks of living trees and also in rock crevices.

In spring, the male sings to defend the territory and to attract a mate. While singing near the female, the male cocks the tail and moves it up and down or from side to side. The wings are half-opened and fluttering. It frequently changes of perch and may also sing while performing short flights. As the female follows it, it shows her each nest built within the territory.
When the birds are near a nest, the male sings loudly while the wings are fluttering. It sings softly at the entrance while the female remains nearby. Then, it enters and leaves the nest several times and the female also enters the nest, moving in and out like the male. The male is very excited when a female visits a nest, singing just at the entrance in crouched posture with lowered, fluttering wings. Then, the male may join her in the nest.
The copulation often occurs on top of large log but also elsewhere. The female solicits the male with quivering wings and calls like a young bird.
Like some other wren species, the Pacific Wren male builds several nests. The female chooses one and both mates complete the nest with plant material, hair and feathers.

The Pacific Wren is a permanent resident in most of the range, N to the coast and islands of Alaska.
Some populations from interior regions move south to spend the winter. Only a few reach the southwest. The movements are nocturnal. The birds breeding at high elevations in mountains perform altitudinal movements after breeding.
The species has wandered to New Mexico.

The Pacific Wren has weak fluttering flight of short duration.

REPRODUCTION OF THIS SPECIES:
The laying takes place from mid-April to May and into mid to late July, depending on the range. This species produces 2-3 broods per season.
The Pacific Wren nests in natural cavity close to the ground, such as a hole among upturned roots of downed tree, or a hole in rotten stump, a rock crevice or even an abandoned woodpecker nest. Inside the cavity, both mates build the nest with grass, moss, weeds, rootlets, and they add a soft lining made of animal hair and feathers.

The female lays 5-6 white eggs with dark dots towards the larger end. She incubates alone during 14-17 days. The young are probably fed by both parents. They leave the nest 14-19 days after hatching, and become independent 9-78 days later.

PROTECTION / THREATS / STATUS:
The Pacific Wren is affected by habitat destruction in NW of the range, involving declines. Severe winters in Alaska, St George Island and Vancouver cause numerous deaths among the populations of this species, and predation by red squirrels involves important numbers of nest failures. Logging of coniferous forests caused the loss of the breeding habitat.
However, the species is described as “common” over most of the range, and it is not globally threatened.
The Pacific Wren is currently evaluated as Least Concern.

Fr: Troglodyte de Baird
Ang: Pacific Wren
All: Pazifikzaunkönig
Esp: Chochín del Pacífico
Nd: Pacifische Winterkoning
Sd: stillahavsgärdsmyg

Photographer:

Tom Grey
Tom Grey's Bird Pictures & Tom Grey's Bird Pictures 2

Text by Nicole Bouglouan

Sources:

HANDBOOK OF THE BIRDS OF THE WORLD Vol 10 by Josep del Hoyo-Andrew Elliott-David Christie - Lynx Edicions - ISBN: 8487334725

WRENS, DIPPERS AND THRASHERS by Brewer David – illustrated by Barry Kent Mackay- Yale University Press - ISBN: 0300090595

Avibase (Denis Lepage)

Birdlife International

Birds of the World

All About Birds

Audubon