Chestnut-backed Chickadee (Poecile rufescens)

Distribution

Year-round range: Extreme western portions of central California north through Oregon, Washington, Canada, British Columbia, to Alaska. A population also exists in northeastern Oregon, eastern Washington, northern Idaho, northwestern Montana, and southeastern British Columbia.

Breeding habitat

Mature conifers, especially low-elevation, coastal, mesic coniferous forests of pines, cedar, tamarack, and hemlock. Typically found in edge habitat, along streams, and in adjacent deciduous woodlands.

Conservation status

This species is of high conservation importance, primarily because of its limited overall range and its association with mature coniferous forests of the Pacific Northwest. Populations appear to be declining in the southern portion of its range (California, Oregon), whereas those in the north are stable, and the interior Rocky Mountain population is showing an increase. Understanding precise habitat requirements, especially sensitivity to fragmentation and various silvicultural practices will be important for maintaining healthy populations of chickadee.

Description

Male: Upperparts are dull chestnut, contrasting sharply with the dark gray tail and flight feathers; crown is dark brown and extends to the upper mantle. Face is white from the cheeks to the sides of the nape, the bib is dark brown and sharply defined. Bright chestnut flanks contrast sharply with the white belly, except in the coastal California race, which have less chestnut on the flanks

Female: Same as adult male.

Juvenile: Same as adults.

Vocalizations

Songs: Lacks a whistled song; but an accelerated series of chips may function as song.

Calls: Calls are generally higher than other chickadees. Typical calls are high, buzzy notes with lower nasal, husky notes: tsidi-tsidi-tsidi-cheer-cheer or a weaker tsity ti jee jee. Some buzzy notes are similar to Dendroica warbler flight calls.

Foraging strategy

Foraging high in trees, gleaning prey from tree bark and foliage. Also gleans prey from tree trunks, as well as rotting logs on the ground.

Diet

A variety of insects and invertebrates, including wasps, beetles, flies, caterpillars, and spiders; also seeds from the cones of coniferous trees, and some fruit pulp.

Behavior and displays

• When disturbed at the nest, the incubating bird hisses and flutters its wings.

Courtship

• No information.

Nesting

Nest Site: Excavate their own nest sites, but will use an existing tree cavity, exceptionally in an artificial nest box. Available tree cavities, particularly in pine, oak, or Douglas fir, or rotted snags suitable for nest excavation are a requirement.

Height: Usually low, up to 10 feet (3 meters) above the ground, can be much higher when in dead trees.

Nest: Not known which sex builds the nest; a cup of moss, bark, grass, ferns fur, hair, and feathers, is placed on a base of thick moss, cup lined with milkweed down, fur, and hair.

Eggs: 6–7 (ranges from 3–9) non-glossy, white or cream eggs are sometimes unmarked, sometimes red, reddish brown, and brown specks are distributed all over the egg or wreathed at the large end of the egg.

Incubation period: Very little information. Incubations appears to be by female only, lasting for 11–12 days.

Nestling period: Very little information. Young are tended to by both parents, and leave the nest at 21 days.

Fledgling period: Very little known, the family may remain on territory, or may move to more optimal habitat.

Broods: No information.

Cowbird Parasitism: Not known to occur.

Notes

• The species is currently undergoing a range expansion to the south and to the east.

• Territorial during the breeding period, although sometimes nest in loose colonies.