brown cap and mostly gray nape; rusty flanks (Alaska, USA; 2009-05-07)

Boreal Chickadee
Poecile hudsonica

Native Range: North America

Notes: a denizen of dense coniferous forests across much of Canada and Alaska; issues a very wheezy call that helps separate it from the equally widespread but much more common Black-capped Chickadee.

brownish-gray upperparts (Alaska, USA; 2009-05-07)