The black-capped chickadee is a small passerine bird that is 12.3-14.6 cm long and weighs 10-14 grams. It builds nests 1-7 meters above the ground during its breeding season from April to June, where the female lays 6-8 white eggs with reddish-brown spots. The eggs hatch after 11-14 days of incubation. To survive cold winters, the chickadee fluffs out its feathers to stay warm instead of hibernating like other birds.