The Ruby-crowned Kinglet is a very small bird, being 9 to 11 cm (3.5 to 4.3 in) long, with a wingspan of 16 to 18 cm (6.3 to 7.1 in), and weighing 5 to 10 g. It has gray-green upperparts and olive-buff( buff is a pale yellow, brown color) underparts. It has two white wingbars and a broken white eye ring. The face and head are plain, the male having a scarlet red crown patch. Female birds are identical to the males (without the crown patch), and young birds are similar to the female.

Habitat and Distribution

Their breeding habitat is coniferous forests across Canada, Alaska, northern New England and the western United States. These birds migrate to the southern United States and Mexico. Some birds are permanent residents in the west.


These birds forage actively in trees or shrubs, mainly eating small insects and spiders, some berries and tree sap. They may hover over a branch while feeding.


The Ruby-crowned Kinglet builds a cup-shaped nest, which may be pensile or placed on a tree branch and is often hidden. It lays up to 12 eggs, and has the largest clutch of any North American passerine for its size.

Calls and Songs

Its song can be divided into three main parts: a series of high pitched notes (zee-zee-zee or tee-tee-tee), two to five low trills (turr or tu), and a repeated three note galloping phrase (tee-da-leet, tee-da-leet).