Boreal chickadee

The boreal chickadee (Poecile hudsonicus) is a small passerine songbird in the tit family Paridae. It is found in the boreal forests of Alaska, Canada and the northern United States and remains within this range all year.<ref name=Weisman2010/> This bird is known for its high pitched trill patterns used in communication with other birds and food storage habits in preparation for winter months.

Description

Adults are Template:Convert long with a weight of Template:Convert. They have grey-brown upperparts with a brown cap and greyish wings and tail; their face is mainly grey with white on the sides. Their underparts are white with brown on the flanks and a black throat. They have a short dark bill, short wings and a long notched tail. Their flight consists of brief gliding patterns followed by fast and bouncy wing beats as they travel through the air.<ref name=Bird/>

Standard Measurements<ref name=BOC /><ref name=Sibley />
length	Template:Convert
weight	Template:Convert
wingspan	Template:Convert
wing	Template:Convert
tail	Template:Convert
culmen	Template:Convert
tarsus	Template:Convert

Vocal communications

The call is a husky tsee-day-day, as well as a high pitched trill sound, dididididididi a variant on the call which gives chickadees their name.<ref name=Bird/> This call is composed of five distinct note-type categories consisting of A, B, C, D and D-hybrid with the beginning and end note both displaying a high frequency pitch.<ref name=Moscicki2011/> Boreal chickadees use specialized notes within their vocal range to communicate with each other and convey information.<ref name=Moscicki2011/> Certain notes/calls can be used as a mating tactic or to indicate a bird's rank to neighbouring fertile females in the area.<ref name=Trout-Haney/> Females have also been known to be more attracted to a male chickadee if he portrays complex and larger song repertoires.<ref name=Trout-Haney/> Calls can also be used in territory defence or to warn others of an invader that come to close to a nesting female.<ref name=Trout-Haney/> Cross species comparisons can be made by comparing the vocal similarities between other species of chickadee's.<ref name=Moscicki2011/>

Breeding/nesting behaviour

Their breeding habitat is coniferous woods in Canada, Alaska, and the northernmost portions of the contiguous United States. They generally breed from early May to the end of August and remain within their breeding range throughout the year, but sometimes move south in winter.<ref name=Trout-Haney/> When a female chickadee finds a high quality male to mate with this provides direct and indirect benefits such as exceptional parental care and high quality genes.<ref name=Trout-Haney/> The pair remains together year round and may mate for life. Winter movements south of their range, however, appear to have become increasingly rare. Large bodies of water and mountain ranges may restrict dispersal of the boreal chickadee into places such as the Vancouver Islands and Haida Gwaii.<ref name=Lait2013/> They nest in a hole in a tree; the pair excavates the nest, using a natural cavity or sometimes an old woodpecker nest. This nest can be made of hair, fur or dead plants.<ref name=Bird/> Five to seven eggs are laid, white with fine reddish-brown spotting.<ref name=BOC/> Eggs are laid between May and July and hatch within 13–16 days.<ref name=Trout-Haney/> After the eggs have hatched it takes another 16–18 days for the birds to fully develop wings large enough to attempt flight.<ref name=Trout-Haney/>

Foraging behaviour

These birds forage on conifer branches or probe into the bark, gleaning insects and foraging for conifer seeds, which may be stored in preparation for winter months.<ref name=Bird/> Boreal chickadees are known to store large amounts of food in different trees, each location containing several food items.<ref name=Haftorn1974/> Food is usually stored in the mid-region of trees at a lower level than at which they foraged.<ref name=Haftorn1974/> They generally forage in black spruce, white spruce and tamarack trees which minimizes competition with black-capped chickadees who forage in more deciduous and mixed forests.<ref name=Gayk2012/> Boreal chickadees often forage in small flocks including other small birds, especially in winter.

Predators

With the advantage of being a winged bird, the boreal chickadee has few predators. These consist of larger birds such as small owls, hawks and shrikes.<ref name=Bird/> Predators of eggs and baby boreal chickadees generally consist of tree climbing animals such as squirrels, chipmunks, mice, bears and rats.<ref name=Mahon2006/>

Threats

The largest threat that is placed on boreal chickadees is clearcutting and logging that occurs in the boreal forest regions.<ref name=Hadley2008/> These practices are causing dramatic reductions in mature forests and rapidly modifying the habitat of boreal chickadees.<ref name=Hadley2008/>

Taxonomy

The species was formerly placed in the genus Parus with most other tits, but mtDNA cytochrome b sequence data and morphology suggest that separating Poecile more adequately expresses these birds' relationships.<ref name=Gill2005/> Molecular phylogenetic studies have shown that the boreal chickadee is sister to the chestnut-backed chickadee (Poecile rufescens).<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref>

External links

• Boreal chickadee Species Account – Cornell Lab of Ornithology
• Template:Usurped at Template:Usurped
• Template:VIREO
• Article on "Maine's Boreal Species" at the Maine Birding Trail
• Template:BirdLife
• Template:Avibase
• Template:InternetBirdCollection
• Template:IUCN Map
• Template:Xeno-canto species
• Template:Field guide birds of the world
• Template:ARKive