The Steller's Jay (Cyanocitta stelleri) is a common bird in forests across much of western North America (from southern Alaska, British Columbia, western Wyoming, and western Colorado and New Mexico west) south through the highlands of Middle America (except Belize) to Nicaragua. These jays occur mainly in coniferous and mixed coniferous-deciduous forest, including humid coniferous forests in northwestern North America and arid pine-oak association in the Middle American highlands.

Except when nesting, Steller's Jays generally live in flocks. They are omnivorous, with a diet that is around two thirds plant material and one third animal. They consume many pine seeds and acorns, especially during fall and winter, as well as many berries and fruits. Especially in summer, many insects are consumed. Other components of the diet include spiders, bird eggs, table scraps, and sometimes small rodents or lizards. Steller's Jays forage mainly high in trees, but they will also feed low or even on the ground.

During courtship, the male feeds the female. Adults are quiet and secretive when nesting, but become noisy and aggressive if the nest is threatened. The nest is usually constructed in a coniferous tree, typically 3 to 9 m above the ground, but sometimes much higher or lower. The nest (built by both sexes) is a bulky and ragged cup of twigs, weeds, moss, and dry leaves cemented together with mud and lined with fine grass, rootlets, and pine needles. Bits of paper are often added to the nest. The 4 eggs (sometimes 3 or 5, rarely 2 or 6) are pale blue-green, finely spotted with brown or olive, and are incubated (mostly or entirely by the female) for 16 to 18 days. Nestlings are fed by both parents. Age of first flight is uncertain, but probably around 3 weeks.

The Steller's Jay is often a permanent (i.e., year-round) resident, but in some areas may move to lower elevations in winter.

(Kaufman 1996; AOU 1998; Dunn and Alderfer 2011)