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The three subspecies of Aphelocoma coerulescens that are found in California are common, and in many places abundant, over almost all the State, except the desert regions and the mountains, but the subject of this sketch, A. c. californica, is confined to a comparatively narrow coastal strip along the southern half of the coast. The 1931 Check-list gives its range as “from the southern arm of San Francisco Bay to the Mexican line, east to the eastern base of the Coast ranges.” But Swarth (1918), who does not recognize A. c. obscura, extends its range into northern Lower California, as far south as the San Pedro Mártir Mountains.

Roughly speaking, the characters distinguishing the three California races are size and color.

Swarth (1918) says that californica, as compared with immanis (now superciliosa), the interior form, “is of small size and dark coloration. The blue areas are of a deeper shade, the back distinctly darker brown, and the light colored under parts have a dusky suffusion. Lower tail coverts usually tinged with blue, sometimes conspicuously so. Coloration is about the same in californica as in oocleptica [the northern coast form], from which subspecies californica is distinguished by smaller size throughout.” The other two races are larger than californica, and both about the same size, but oocleptica is dark colored and superciliosa is much paler.

The habitats of the three races and their general habits are all very similar. One life history might well do for all three. They all live mainly in the Upper Sonoran Zone, with some extension of range into the Lower Sonoran and Transition Zones. Their favorite haunts are the oak and brush-covered foothills of the mountains, the brush-covered sides of the canyons, the oak and digger-pine chaparral, thickets of Ceanothus and poison-oak bushes, and among the small trees and shrubbery along watercourses. In such places, where there is ample concealment among the thick foliage, this handsome, flat-headed, mischievous villain is quite sure to be found; if not immediately in evidence, the well-known squeaking sound, such as one uses to call small birds, will bring all the jays within hearing of it.

Nesting.—Major Bendire (1895) writes:

The nests are usually found on brush-covered hillsides or in creek bottoms, placed in low bushes and thickets, such as blackberry, poison oak, wild gooseberry, currant, hazel, hawthorn, and scrub-oak bushes, or in osage-orange hedges; occasionally in a small piñon pine or a bushy young fir, and quite frequently on a horizontal limb of an oak, varying in height from 3 to 30 feet from the ground. In the majority of cases the nests are located near water, but sometimes one may be found fully a mile distant. Externally they are composed of a platform of interlaced twigs, mixed occasionally with moss, wheat stubble, and dry grass; on this the nest proper is placed, which consists of a lining of fine roots, sometimes mixed with horsehair. No mud enters into the composition of their nests. One now before me * * * measures 9 inches in outer diameter by 3½ inches in height; the inner cup is 4 inches in diameter by 2 inches deep. Outwardly it is composed of small twigs of sagebrush, and the lining consists entirely of fine roots; it is compactly built and well constructed. The nests are usually well concealed, and the birds are close sitters, sometimes remaining on the nests until almost touched.

In addition to the trees and shrubs mentioned above, nests of the California jay have been found in live oaks, elders, willows, apple trees, pear trees, junipers, cypresses, and honeysuckles. W. L. Dawson (1923) says:

Taking the country over, nests built in oak trees probably outnumber all others combined, yet the component members of the chaparral, ceanothus, chamissal, and the rest, must do duty in turn, and all species of the riparian sylva as well. The thick-set clumps of mistletoe are very hospitable to this bird, and since this occurs on oaks, cottonwoods, and, occasionally, digger pines, it follows that jay-heim is found there also. * * *

The lining varies delightfully, but is largely dependent, it is only fair to say, upon the breed of horses or cattle affected on the nearest ranch. So we have nests with white, black, bay, and sorrel linings, not to mention dapple gray and pinto. One fastidious bird of my acquaintance, after she had constructed a dubious lining of mottled material, discovered a coal black steed overtaken by mortality. New furnishings were ordered forthwith. The old lining was pitched out bodily, and the coal black substitute installed immediately, to the bird’s vast satisfaction—and mine.

Eggs.—Four to six eggs generally constitute a complete set for the California jay; as few as two and as many as seven have been recorded. The eggs are usually ovate in shape, rarely elongate-ovate. They are very beautifully colored and show a wide range of variation, seldom, if ever, equaled and never exceeded among North American birds’ eggs. In any series of these colorful eggs there are apparent two quite distinct types of coloration, the green and the red. Lawrence Stevens, of Santa Barbara, writes to me that about half of the sets that he takes are of the green type and half of the red type. He finds eggs of the green type mostly in the creek bottoms in willows, usually in sets of four, and finds eggs of the red type mostly on the hillsides, in sets of five. As several other collectors do not agree with him on these points, there is probably no correlation of color with the locality or the size of the set. He mentions one set that has a cream-colored background with red spots, that one would hardly believe to be jays’ eggs.

James B. Dixon tells me that only about two sets in ten are of the red type. Dawson (1923) describes the colors very well as follows:

The red type is much the rarer. In this the ground color varies from clear grayish white to the normal green of the prevailing type; while the markings—fine dots or spots or, rarely, confluent blotches—are of a warm sepia, bister, verona brown, or Rood’s brown. The ground color of the green type varies from pale sulphate green to lichen green, and the markings from deep olive to Lincoln green. In the Museum of Comparative Zoology we have a set kindly furnished by Mr. H. W. Carriger, whose markings are reduced to the palest subdued freckling of pea-green. In another set of the red type, fine Mars brown markings of absolute uniformity cover the egg; while the eggs of another set are covered as to their larger ends with an olive-green cloud cap, which leaves the remainder of the specimen almost free of markings.

Bendire (1895) describes the eggs somewhat differently as follows: “The ground color of the egg of the California Jay is very variable, ranging from deep sea green to pea and sage green, and again to dull olive and vinaceous buff. The eggs with the greenish ground color usually have markings of a dark bottle-green tint, mixed sometimes with different shades of sage green. The eggs having a buffy ground color are spotted, blotched, and speckled with different shades of ferruginous, cinnamon, rufous, and occasionally lavender. The markings are generally scattered over the entire surface of the egg, and are usually heavier about the larger end, but nowhere so profuse as to hide the ground color.”

The measurements of 50 eggs average 27.6 by 20.5 millimeters; the eggs showing the four extremes measure 30.6 by 21.8, 30.2 by 22.4, 24.4 by 19.3, and 25.4 by 18.8 millimeters.

Young.—Bendire (1895) says that the male assists “to some extent in incubation, which lasts about sixteen days. The young are able to leave the nest in about eighteen days, and follow the parents for some time.” Mrs. Wheelock (1904) says that “the male assists in the nest-building, but not in the incubation. The latter requires fourteen days. * * * One of the first lessons the young Jays learn is to love the water. It requires some coaxing for the first splash, but they seem to take to their bath as do little ducks, and to find it just as necessary as food.”

Plumages.—The young jay is hatched naked and blind; probably some form of natal down appears in advance of the Juvenal plumage, though I have not seen it. Ridgway (1904) gives the following detailed description of the juvenal plumage: “Pileum, hind neck, auricular and suborbital regions, sides of chest, rump, and upper tail-coverts uniform mouse gray, the pileum slightly more bluish gray; back, scapulars, and lesser wing-coverts deep drab-gray; lores dusky; a broad postocular and supra-auricular space, narrowly streaked with dusky gray; anterior portion of malar region, chin, throat, median portion of chest and under parts generally white, faintly tinged across upper breast and on anterior portion of sides with very pale brownish gray; wings (except smaller coverts) and tail as in adults.”

The postjuvenal molt begins early in July, and I have seen a young bird beginning to molt on the throat and upper breast as early as June 29. This molt involves all the contour plumage and the lesser wing coverts, but not the rest of the wings and tail. I have seen no specimens showing the latter part of this molt, but it is apparently completed before September, when young birds become practically adult.

Adults have a complete postnuptial molt, which seems to be accomplished mainly in August; the plumage becomes much worn and faded during late spring and early summer, the blue wearing off on the head, exposing the dusky bases of the feathers, the brown of the back fading, and the under parts becoming soiled and browner; I have seen birds molting in August and others in full fresh plumage as early as September 24.

Food.—Prof. F. E. L. Beal (1910) examined 326 stomachs of the California jay, and found that 27 percent of the food consisted of animal matter and 73 percent vegetable, though the animal matter amounted to 70 percent in April. Among the insect food, he lists predaceous ground beetles, mostly beneficial species, 2.5 percent for the year and as much as 10 percent in April; other beetles, mostly harmful, 8 percent for the year and 31 percent in April; wasps, bees, and ants amounted to less than 5 percent; honey bees were found in 9 stomachs, and all, 20 in number, were workers; Lepidoptera, mainly in the caterpillar stage, amounted to 2.5 percent; this item included 12 pupae of the coddling moth, an unexpected service that would cover a multitude of sins in other directions; grasshoppers and crickets were eaten to the extent of 4.5 percent. Of other animal food, he says: “A few miscellaneous creatures, such as raphidians, spiders, snails, etc., form less than one-half of 1 percent of the food. * * * Besides the insects and other invertebrates already discussed, the jay eats some vertebrates. The remains consisted of bones or feathers of birds in 8 stomachs, eggshells in 38, bones of small mammals (mice and shrews) in 11, and bones of reptiles and batrachians in 13 stomachs.” In destroying small mammals the jay does good service, as most of them are injurious, but the same cannot be said about its appetite for the useful reptiles and batrachians. The damage to the eggs and young of small birds is a serious matter. Some 95 stomachs were collected between the middle of May and the middle of July, the height of the nesting season, “of which 17, or 18 percent, contained eggs or remains of young birds. If we may infer, as seems reasonable, that 18 percent of the California jays rob birds’ nests every day during the nesting season, then we must admit that the jays are a tremendous factor in preventing the increase of our common birds. Mr. Joseph Grinnell, of Pasadena, after careful observation, estimates the number of this species in California at about 126,000. This is probably a low estimate. If 18 percent of this number, or 22,680 jays, each robs a nest of eggs or young daily for a period of sixty days from the middle of May to the middle of July, the total number of nests destroyed in California by this one species every year is 1,360,800.”

Mr. Dawson (1923) draws a still blacker picture; he figures, on the basis of suitable acreage and average population per acre, that there are 499,136 pairs of California jays in the State and says: “If we allow only one set of eggs or nest of birds to each pair of jays per diem for a period of two months, we shall be well within the mark of actuality. Yet that will give us in a season a total destruction of 29,948,160 nests, or, say, 100,000,000 eggs.” These figures look appalling, but, in considering them, we must not lose sight of three important facts: First, jays and small birds have existed together for untold ages without any serious reduction in the number of the latter; second, the increase in small birds is limited by the amount of suitable area that will support them, and such area is probably kept filled to capacity; and third, it is a well-known fact that if a pair of birds is robbed of its eggs a second or third set will be laid; this is less likely to happen, however, if the young are taken.

But wild birds are not the only sufferers from the depredations of this jay; the eggs and young of domestic poultry are preyed upon. Professor Beal (1910) writes:

He is a persistent spy upon domestic fowls and well knows the meaning of the cackle of a hen. A woman whose home is at the mouth of a small ravine told the writer that one of her hens had a nest under a bush a short distance up the ravine from the cottage. A jay had found this out, and every day when the hen went on her nest the jay would perch on a near-by tree. As soon as the cackle of the hen was heard, both woman and bird rushed to get the egg, but many times the jay reached the nest first and secured the prize. * * *

A still worse trait of the jay was described by a young man engaged in raising poultry on a ranch far up a canyon near wooded hills. When his white leghorn chicks were small, the jays would attack and kill them by a few blows of the beak, and then peck open the skull and eat the brains. In spite of all endeavors to protect the chicks and to shoot the jays, his losses were serious.

Of the vegetable food, mast, mainly acorns, is the largest item, and during the late fall and winter months made up one-half to three-quarters of the entire food; October showed the largest amount, 88.57 percent. Acorns and nuts are carried off and stored wherever they can be hidden in cracks and crevices, but since many are dropped on the way, or hidden on the ground, the jay may be considered useful as a tree planter.

Grain constitutes an important item; in March, when grain was being sown, it amounted to 45.50 percent; and again, during the harvesting season in September, it made up 24.26 percent of the food. “Grain was found in 95 stomachs, of which 56 contained oats; 34, corn; 2, wheat; 2, barley; and 1, grain not further identified. Many of the oats were of the wild variety.

“Fruit was found in 270 stomachs. Of these, cherries were identified in 37, prunes in 25, apples in 5, grapes in 2, pears in 2, peaches in 1, gooseberries in 2, figs in 1, blackberries or raspberries in 71, elderberries in 42, manzanita in 4, cascara in 1, mistletoe in 1, and fruit pulp not further identified in 76.” He remarks, further, that “it is safe to say that half of the fruit eaten was of wild varieties and of no economic value.” His table shows that fruit formed 22.05 percent of the total food for the year but averaged nearly half of it during the summer months and 61.41 percent in May. In addition to what fruit the jay eats, much more is damaged and left on the trees to rot and more falls to the ground.

Robert S. Woods writes to me: “The California jay is very destructive to almonds and finds no difficulty in cracking the harder-shelled varieties. Its raids begin before the nuts are ripe enough for human consumption and continue as long as any of the crop remains. The almond is held against a branch with the foot and vigorously pounded with the bill until an opening is made large enough to permit the kernel to be extracted piecemeal. English walnuts are broken into while still on the tree. However, the Eureka variety, at least, seems to be immune after the shell has thoroughly hardened, though some of the thinner-shelled strains or varieties could doubtless be successfully attacked even after maturity.

“Jays will often eat dry bread crumbs but greatly prefer food of a more fatty nature. When coarsely chopped suet is placed on a feeding table, it is ignored by most of the local dooryard birds, but the jays will diligently carry away and hide the pieces until all are gone.”

From the foregoing evidence it may be seen that the California jay has more faults than virtues. It has few redeeming traits, and economically it does more harm than good. Its beauty and its lively manners make it an attractive feature in the landscape, but it may be that there are too many jays in California.

Behavior.—There is much in the actions of the California jay that reminds one of our familiar eastern blue jay; it is a handsome villain, but one misses the jaunty crest. It is far less shy, much bolder, more impertinent, and more mischievous. Its flight is just as slow and apparently laborious, accomplished by vigorous, heavy flappings of its wings on its usually short flights; it lives mostly at the lower levels among the trees and shrubbery and may often be seen sailing down over a brush-covered hillside with its blue wings and tail widely spread; as it glides upward to its perch it greets the observer with its harsh cries. It is quick and agile in all its movements, as it darts about through the underbrush, where it searches diligently for small birds’ nests, or follows the little birds about to learn their secrets. It is not above picking a quarrel with the California woodpecker, whose stores it probably wants to steal, but, like most thieves, it is a cowardly bird and often needs the support of its fellow brigands. It is cordially disliked and dreaded by all the smaller birds. It is a nuisance, too, to the sportsman or the bird student, as its curiosity leads it to follow a human being about and proclaim his presence in such a loud voice that every creature within hearing is warned to disappear.

This jay seems to have a sense of humor or a fondness for play. Joseph Mailliard (1904) gives an amusing account of the behavior of California jays with his cats, stealing their food and teasing them. While a jay is attempting to steal food from a cat, “each has the measure of the other, and while a cat is watching, it is rarely that a jay approaches within reach of its business end, though it will do all it can to make the cat jump at it, or at least turn away. Grimalkin has learned to keep her tail well curled up when feeding, as a favorite trick of the jay is to give a vigorous peck at any extended tail and, when the cat turns to retaliate, to jump for the prize and make off with shrieks of exultation. * * * To find a cat napping, with its tail partially extended is absolute joy to one of these birds, which will approach cautiously from the rear, cock its head on one side and eye that tail until it can no longer resist the temptation, and, finally after hopping about a few times most carefully and noiselessly, Mr. (or Mrs.) Jay will give the poor tail a vicious peck and then fly, screeching with joy, to the nearest bush.”

One day, after one of the cats had hidden her newly born kittens in the garden, “a faint mewing outside the window attracted the attention of someone in the kitchen when lo and behold there was a jay hauling a very young kitten out from under a young artichoke plant in the garden. The jay lugged the poor kitten along for a little way, seeming to enjoy its feeble wails, and then stopped and screeched in exultation over the find, only to repeat the process again and again. Needless to say the old cat was not present at the moment or things would have been made more lively. The bird certainly did not want to eat the kitten, and the affair seems to have been nothing else than a matter of pure mischief.”

Voice.—Mrs. Bailey (1902) describes this jay’s voice very well as follows: “The Aphelocoma voice differs strikingly from that of frontalis, having a flat tone and being uttered with unseemly haste. Its notes vary greatly in expression and are so emphatic and often peremptory that one cannot doubt that something important is being said. A favorite cry, used apparently to rouse attention, is quick ‘quay-quay-quay-quay-quay-quay-quay.’ Another still more emphatic one is boy’ee boy’-ee while an inquiring quay-kee? is often heard. Sometimes when a jay flies down to a companion it gives its quay-quay-quay-quay-quay and is answered by a high-keyed queep-queep-queep-queep—however that may be interpreted.”

Ralph Hoffmann (1927) says that “the California Jay utters a succession of harsh cries like the syllable tschek, tschek, slightly higher pitched than those of the Steller Jay. Another note commonly uttered when the bird is perched is a very harsh ker-wheek.” James B. Dixon tells me that “the male has a very pleasing ventriloquial song, which he sings during the mating season and which can be heard only a very short distance.”

Field marks.—A flat, crestless, blue head, a pale brown back, blue wings and tail, and a white-streaked throat will serve to distinguish this species from the much darker crested jays of the stelleri group. Its jay-like behavior and its loud voice make it conspicuously different from other birds.

Enemies.—Jays are probably sometimes attacked by predatory birds and animals, but they are fairly well able to take care of themselves and defend their eggs and young. Man seems to be their bitter enemy. Large numbers are shot every year by farmers and fruit growers where the jays are damaging their crops. Organized jay shoots are popular in some parts of California, under the pretext of reducing the numbers of a destructive bird, but largely, too, as a pleasant recreation and an interesting competition for the shooters; dealers in ammunition also find it profitable. Dr. Mary M. Erickson (1937) witnessed one of these shoots and has published an interesting article on it. She says:

Jay shoots have been held in Calaveras County for many years. Two persons reported that hunts have taken place about once a year during the eleven and fourteen years they had lived in the vicinity. Two old-time residents said that occasional shoots had been held thirty or forty years previously. Recently, one or two shoots a year have been held, usually in the fall, sometimes in the spring, but the time of year and the number are irregular. The last shoot had been held on October 20, 1935, when, according to a local newspaper, 1368 jays were killed. The shoots, at least in recent years, have been conducted as contests between two teams, and after the count there has been a dinner, or as this year, a barbecue in which wives and friends shared, at the expense of the losing side.

In the shoot that she witnessed, 398 California jays, 214 Steller’s jays, 1 red-tailed hawk, 1 Cooper’s hawk, and 3 sparrow hawks were brought in. She estimated that an area of approximately 200 square miles was covered in the hunt, but probably not with systematic thoroughness. “On the day before the shoot, fifteen hours were spent by Mr. Hooper and me in taking a census in three sample areas of typical jay habitat, and every effort was made to get an accurate count. On this meagre basis, the population is estimated as one jay, either California or Steller, for every 5½ acres of suitable habitat, or 118 jays per square mile of such habitat. * * * In comparison with these figures, an estimate for Calaveras County of one jay for every 5½ acres, in an acre of equally good or better habitat, does not seem excessive. Assuming that only half of the total area is suitable for occupancy by jays, the jay population of the 200 square miles in which the hunting was most concentrated, would be 11,636. On this basis, the shooting of 612 jays resulted in destruction of about 5 per cent of the jay population.”

The shoot in which these 612 jays were killed was at the beginning of the nesting season, when it would have the maximum effect on the breeding population. She reasons that “the shoot held in the fall of 1935 when the population was near its maximum, probably did not eliminate more than 5 per cent of the next breeding population [italics mine], even though twice as many were killed, for part of the kill was composed of birds which in time would have been destroyed by natural forces.”

Probably this 5 percent reduction in numbers, even if accomplished every year, would have no appreciable effect on the year to year population of jays. For it is a well-known fact that every suitable habitat is filled up to its capacity to support the species; and that the removal of a few individuals makes it just so much easier for others to survive, or to drift in from outside. Natural causes probably eliminate much more than 5 percent of the species each year, but any release of pressure enables the species to expand and fill in the gap. Any attempt at a wholesale and systematic elimination of the California jays, that would be effective, would prove very expensive and would probably not succeed.