The family Corvidae includes 20 species found in North America.

The corvines are mostly medium to large in size, ranging from 25 cm to 66 cm. The bill is stout, moderately long, often with a small hook. Many species of crows and ravens are black, some with white, gray or brown areas. Jays and magpies are usually brightly colored with blues and greens, some with long tails and some jays are crested. Sexes are alike. They tend to be omnivorous and to build open, cup-shaped nests of twigs lined with fine plant material.

Crow and raven species are omnivorous, with insects and other invertebrates composing most of their diet, plus fruits, small vertebrates, nestlings and eggs, etc. The Raven and other large species often take birds and small mammals. Carrion is eaten by many or all species. Most, perhaps all, species store food. Nests are built by both sexes; bulky structures of twigs, often with mud, mammal dung or earth included, lined with finer materials, placed in a tree, on a cliff, building or on the ground. Eggs usually 3-5, range 2-9; color variable but commonly greenish to whitish with brown and gray markings. Incubation by female; 16-18 days in small species, up to 18-20 days in Raven; fledging 30-35 days in smaller species, 6 weeks in Raven. Male feeds female during incubation, but female also leaves nest to feed; both sexes feed the young. Asynchronous hatching in large broods, smaller young often die. Young fed for varying periods after fledging. Age at first breeding usually 2 years in smaller species, probably 2-3 years in largest species. 

The Jays are omnivorous, taking a range of nuts, seeds, fruits and small animals, including insects, bird's eggs, nestling birds and mice. Nest of twigs, bark, grass, etc., usually bound together with mud; lined with fine plant fibers; both sexes build; usually in a tree or bush, rarely in a tree cavity. Eggs 2-6, usually 4-5, variable in color. Incubation mainly by female, rarely by male; female fed on and off the nest by the male; incubation 16-18 days, young fledge at 17-21 days; young fed by both parents, only female broods; young fed for 1-2 months after fledging. No evidence of communal breeding. Age at first breeding usually 2 years, rarely 1 year.

In the Florida Scrub-Jay about half of the territories are occupied by a single pair, the other half by a monogamous adult pair with 1-3, rarely up to 8, helpers, usually offspring of previous 1 or 2 years. Mated pairs remain together for life; longest known surviving pair bred together for 8 years. Age at first breeding 2 years for about half, 3 years for most; females earlier than males The Western Scrub-Jay in California seems to be a monogamous breeder.