Читать книгу Life Histories of North American Jays, Crows, and Titmice - Arthur Cleveland Bent - Страница 42
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Harry S. Swarth (1918) gave the above name to the flat-headed jays of “the coast region of northern California, west from Mount Diablo and the coast ranges. North to Humboldt Bay, south to the Golden Gate and the east side of San Francisco Bay.” Of its distinguishing characters, he says: “Of large size and dark coloration. In color closely similar to A. c. californica, but size measurably greater throughout. In measurements oocleptica is equal to the maximum of immanis, from which subspecies it is distinguished by its dark coloration. Differs from hypoleuca both in greater size and much darker color.”
Nesting.—There is not much to be said about the nesting habits of the Nicasio jay, which are practically the same as those of the other California subspecies. John W. Mailliard (1912) says that this jay is an abundant resident in Marin County and that their “nesting notes upon this species established the following sites for the eighty-three nests observed: oaks 69; bay 3; wild coffee 4; elder 2; madrona 1; gooseberry 1; toxon 1; poison oak 2. And yet in Belvedere, Marin County, where live-oaks are most plentiful, a nest has been built almost yearly, for seven or eight years, in a clematis which climbs up the side of our summer home. The nest has usually been placed within reach of, as well as observation from, the window of a constantly occupied bed room, a window opening out and frequently opened and closed daily.”
Eggs.—The eggs of the Nicasio jay are practically indistinguishable from those of the California jay and show the same interesting variations. The measurements of 40 eggs average 27.8 by 20.5 millimeters; the eggs showing the four extremes measure 30.8 by 21.8, 29.0 by 22.4, 24.4 by 19.3, and 25.4 by 18.8 millimeters.
Food.—The notes that Charles A. Allen, of Nicasio, Calif., sent to Major Bendire (1895) evidently refer to this race. He writes:
No bird is more destructive of the smaller species building open, unconcealed nests than this Jay. I have seen one alight on a limb near a nest, eat the eggs that it contained, and, not satisfied with this, give the nest a down and inward stroke with its bill, ripping it open. They are especially destructive to the nests of the Black-chinned and Anna’s Hummingbirds and the Ground Tit. They also become altogether too familiar about the poultry houses, and will eat the eggs as fast as the hens lay them. As soon as they hear a hen cackle after laying, three or four of these birds go to the spot at once. Even the chicken house affords no protection against these robbers, if they can find a way of entering it; shooting is equally ineffectual, for they are too numerous. They destroy vast quantities of fruit in apple, peach, pear, and plum orchards, as well as many smaller fruits. Shooting them by hundreds and hanging their carcasses in the fruit trees as scarecrows is of no avail; they do not know enough to be frightened at anything. I have tried to poison them, but never saw a dead one except when shot. They also destroy a great deal of young wheat when first sown, until it is 2 or 3 inches high. They pull it out of the ground and eat the soft, swelled grains; after the stalks begin to grow they will not molest it.
One cannot help feeling that the above bitter invective is somewhat overdrawn and perhaps a bit prejudiced. His statement that they “do not know enough to be frightened” is offset by the fact that he was never able to poison one; the truth of the matter probably is that they know too much to be frightened unnecessarily, and that they are crafty enough to avoid real danger. His statement that they pull up sprouting grain does not agree with Professor Beal’s (1910) statement that “the jay is not known to pull up grain after it has sprouted.”
But Professor Beal evidently overlooked Mr. Allen’s statement, as well as the following from Joseph Mailliard (1900): “I have had acres of peas * * * practically destroyed by these birds. * * * I remember one spring when a patch of about an acre and a half was sown with a mixture of peas and oats, and the peas were pulled up as fast as sprouted, by the jays, so that the crop consisted of oats alone. * * * Some years they destroy a lot of corn and other years almost none. * * * This year the Jays, in conjunction with Towhees, Juncos and a few Flickers, badly damaged some late sown oats beside the house.” He watched them through glasses and saw them pull up the sprouting grain and eat the kernels.
Professor Beal (1910) adds the following observation in the jay’s favor: “But the jays do not frequent orchards entirely for fruit. During May and June the writer many times visited an apple orchard, the leaves of which were badly infested with a small green caterpillar, locally known as the canker worm. When a branch is jarred, these insects let themselves down to the ground on a thread spun for the purpose. Many jays were seen to fly into the orchard, alight in a tree, and then almost immediately drop to the ground. Observation showed that the caterpillars, disturbed by the shock of the bird’s alighting on a branch, dropped, and that the birds immediately followed and gathered them in. These caterpillars were found in the stomachs of several jays, in one case to the extent of 90 percent of the contents.”
Voice.—Mr. Allen mentions some notes of this jay that are somewhat different from those recorded by others; he wrote to Major Bendire (1895): “One of their notes of alarm, uttered when they see something they do not like, especially an Owl asleep in a tree, sounds like ‘cǔr, cǔr, cǔr’; as soon as this is heard by others in the vicinity they will commence to gather and join in the chorus. A sort of social note of recognition sounds like ‘whǔze, whǔze’, given while moving about among the trees and shrubbery, and one of their common call notes sounds like ‘creak, creak’.”
