This list of California birds is a comprehensive listing of all the bird species seen naturally in the U.S. state of California as determined by the California Birds Records Committee (CBRC).
There are, as of 2009, 641 species on this list. Fifteen of these species are introduced (I)–species that are non-native to California but now have established populations. Two of these species are extirpated (E)–species that are native to California but no longer have established populations there (they still do in other places). Birds marked with an asterisk (*) are currently under review by the CBRC. The CBRC states the following about birds under review:
The California Bird Records Committee solicits information on all occurrences in California of the 180 species on this Review List, as well as species unrecorded in California. In general, review species average four or fewer occurrences per year in California, and have been recorded fewer than 100 times.
This list is presented in taxonomic order and follows The Check-list of North American Birds (7th ed., 1998), published by the American Ornithologists' Union. The table of contents is grouped into passerines (the largest order of birds) and non-passerines. The family accounts at the beginning of each heading reflect this taxonomy, as do the species counts found in each family accounts.
The family Anatidae includes the ducks and most duck-like waterfowl, such as geese and swans. These are birds that are modified for an aquatic existence with webbed feet, bills which are flattened to a greater or lesser extent, and feathers that are excellent at shedding water due to special oils.Stercorariidae==Old World flycatchers== Order: Passeriformes. Family: Muscicapidae
The Phasianidae is a family of birds which consists of the pheasants and their allies, including partridges, grouse, turkeys, and Old World Quail. These are terrestrial species, variable in size but generally plump, with broad relatively short wings. Many species are gamebirds, or have been domesticated as a food source for humans.Stercorariidae==Old World flycatchers== Order: Passeriformes. Family: Muscicapidae
The New World quails are small, plump terrestrial birds only distantly related to the quails of the Old World, but named for their similar appearance and habits.Stercorariidae==Old World flycatchers== Order: Passeriformes. Family: Muscicapidae
Loons are aquatic birds size of a large duck, to which they are unrelated. Their plumage is largely grey or black, they have spear-shaped bills. Loons swim well, and fly adequately, but, because their legs are placed towards the rear of the body, are almost hopeless on land.Stercorariidae==Old World flycatchers== Order: Passeriformes. Family: Muscicapidae
Grebes are small to medium-large sized freshwater diving birds. They have lobed toes, and are excellent swimmers and divers. However, they have their feet placed far back on the body, making them quite ungainly on land.
The storm-petrels are the smallest of seabirds, relatives of the petrels, feeding on planktonic crustaceans and small fish picked from the surface, typically while hovering. The flight is fluttering and sometimes bat-like.
Cormorants are medium-to-large aquatic birds, usually with mainly dark plumage and areas of coloured skin on the face. The bill is long, thin, and sharply hooked. Their feet are four-toed and webbed, a distinguishing feature among the Pelecaniformes order.
Frigatebirds are large sea-birds usually found over tropical oceans. They are large, black or black and white, with long wings and deeply-forked tails. The males have inflatable coloured throat pouches. They do not swim or walk, and cannot take off from a flat surface. Having the largest wingspan to body weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week.
The family Ardeidae contains the herons, egrets, and bitterns. Herons and Egrets are medium to large sized wadng birds with long necks and legs. Bitterns tend to be shorter necked and more secrative. Unlike other long necked birds such as storks, ibises and spoonbills, members of Ardeidae fly with their necks retracted.
Storks are large, heavy, long-legged, long-necked wading birds with long stout bills and wide wingspans. They lack the powder down that other wading birds such as herons, spoonbills and ibises use to clean off fish slime. Storks lack a pharynx and are mute.
The New World vultures are not closely related to Old World vultures, but superficially resemble them because of convergent evolution. Like the Old World vultures, they are scavengers. However, unlike Old World vultures, which find carcasses by sight, New World vultures have a good sense of smell with which they locate carcasses.
The family Accipitridae is a family of birds of prey and include hawks, eagles, kites, harriers and Old World vultures. These birds have very large powerful hooked beaks for tearing flesh from their prey, strong legs, powerful talons, and keen eyesight.
Rallidae is a large family of small to medium-sized birds which includes the rails, crakes, coots, and gallinules. The most typical family members occupy dense vegetation in damp environments near lakes, swamps, or rivers. In general they are shy and secretive birds, difficult to observe. Most species have strong legs, and have long toes which are well adapted to soft, uneven surfaces. They tend to have short, rounded wings and be weak fliers.
Cranes are large, long-legged and long-necked birds. Unlike the similar-looking but unrelated herons, cranes fly with necks outstretched, not pulled back. Most have elaborate and noisy courting displays or "dances".
The family Charadriidae includes the plovers, dotterels, and lapwings. They are small to medium-sized birds with compact bodies, short, thick necks and long, usually pointed, wings. They are found in open country worldwide, mostly in habitats near water, although there are some exceptions.
Recurvirostridae is a family of large wading birds, which includes the avocets and the stilts. The avocets have long legs and long up-curved bills. The stilts have extremely long legs and long, thin, straight bills.
The Scolopacidae are a large diverse family of small to medium sized shorebirds including the Sandpipers, Curlews, Godwits, Shanks, Tattlers, Woodcocks, Snipes, Dowitchers and Phalaropes. The majority of species eat small invertebrates picked out of the mud or soil. Different lengths of legs and bills enable different species to feed in the same habitat, particularly on the coast, without direct competition for food.
Laridae is a family of medium to large birds seabirds and includes gulls, terns, kittiwakes and skimmers. They are typically grey or white, often with black markings on the head or wings. They have stout, longish bills and webbed feet.
Alcids are superficially similar to penguins due to their black-and-white colours, their upright posture and some of their habits, however they are not related to the penguins at all, being able to fly. Auks live on the open sea, only deliberately coming ashore to nest.
Parrots are small to large birds with a characteristic curved beak shape. Their upper mandibles have slight mobility in the joint with the skull and they have a generally erect stance. All parrots are zygodactyl, having the four toes on each foot placed two at the front and two back.
The family Cuculidae includes cuckoos, roadrunners and anis. These birds are of variable size with slender bodies, long tails and strong legs. Unlike the cuckoo species of the Old World, North American cuckoos are not brood parasites.
Typical owls are small to large solitary nocturnal birds of prey. They have large forward-facing eyes and ears, a hawk-like beak, and a conspicuous circle of feathers around each eye called a facial disk.
Nightjars are medium-sized nocturnal birds with long wings, short legs and very short bills that usually nest on the ground. Most have small feet, of little use for walking, and long pointed wings. Their soft plumage is crypically coloured to resemble bark or leaves. * Lesser Nighthawk, Chordeiles acutipennis
The swifts are small aerial birds, spending the majority of their lives flying. These birds have very short legs and never settle voluntarily on the ground, perching instead only on vertical surfaces. Many swifts have long swept-back wings that resemble a crescent or a boomerang.
Woodpeckers are small to medium sized birds with chisel like beaks, short legs, stiff tails and long tongues used for capturing insects. Some species have feet with two toes pointing forward, and two backward, while several species have only three toes. Many woodpeckers have the habit of tapping noisily on tree trunks with their beaks.
Tyrant flycatchers are Passerine birds which occur throughout North and South America. They superficially resemble the Old World flycatchers, but are more robust with stronger bills. They do not have the sophisticated vocal capabilities of the songbirds. Most, but not all, are rather plain. As the name implies, most are insectivorous.
Shrikes are passerine birds known for their habit of catching other birds and small animals and impaling the uneaten portions of their bodies on thorns. A typical shrike's beak is hooked, like a bird of prey.
The Corvidae family includes crows, ravens, jays, choughs, magpies, treepies, nutcrackers, and ground jays. Corvids are above average in size for the bird order Passeriformes. Some of the larger species show levels of learned behavior of a high degree.
The Hirundinidae family is a group of passerines characterised by their adaptation to aerial feeding. Their adaptations include a slender streamlined body, long pointed wings and short bills with wide gape. The feet are designed for perching rather than walking, and the front toes are partially joined at the base.
Nuthatches are small woodland birds. They have the unusual ability to climb down trees head first, unlike other birds which can only go upwards. Nuthatches have big heads, short tails and powerful bills and feet.
Treecreepers are small woodland birds, brown above and white below. They have thin pointed down-curved bills, which they use to extricate insects from bark. They have stiff tail feathers, like woodpeckers, which they use to support themselves on vertical trees.
The Thrushes are a group of passerine birds that occur mainly but not exclusively  in the Old World. They are plump, soft plumaged, small to medium sized insectivores or sometimes omnivores, often feeding on the ground. Many have attractive songs.
The Mimids are a family of passerine birds that includes thrashers, mockingbirds, tremblers, and the New World catbirds. These birds are notable for their vocalization, especially their remarkable ability to mimic a wide variety of birds and other sounds heard outdoors. The species tend towards dull grays and browns in their appearance.
Starlings are small to medium-sized Old World passerine birds with strong feet. Their flight is strong and direct, and most are very gregarious. Their preferred habitat is fairly open country, and they eat insects and fruit. The plumage of several species is dark with a metallic sheen.
The waxwings are a group of passerine birds characterised by soft silky plumage and unique red tips to some of the wing feathers. In the Bohemian and Cedar Waxwings, these tips look like sealing wax, and give the group its name. These are arboreal birds of northern forests. They live on insects in summer and berries in winter.
The Emberizidae are a large family of passerine birds. They are seed-eating birds with a distinctively shaped bill. In Europe, most species are named as buntings. In North America, most of the species in this family are known as Sparrows, but these birds are not closely related to the Old World sparrows which are in the family Passeridae. Many emberizid species have distinctive head patterns. There are species 275 world wide, 60 North American species, and 38 Californian species.
The Icterids are a group of small to medium, often colourful passerine birds restricted to the New World and include the grackles, New World blackbirds, and New World orioles. Most species have black as a predominant plumage colour, often enlivened by yellow, orange or red.
Finches are seed-eating passerine birds, that are small to moderately large and have a strong beak, usually conical and in some species very large. All have 12 tail feathers and 9 primaries. These birds have a bouncing flight with alternating bouts of flapping and gliding on closed wings, and most sing well.
Old World sparrows are small passerine birds. In general, sparrows tend to be small plump brownish or greyish birds with short tails and short powerful beaks. Sparrows are seed-eaters, and they also consume small insects.