“During the present year, the writer came upon his first example of sapsucker work on so-called second-growth redwood. * * * The sapsuckers attacked every tree in two groups, or families, of sprouts.”
W. L. Dawson (1923) writes:
The red-breasted sapsucker does puncture trees and drink sap both in summer and winter. In summer it attacks in this fashion not only pine, fir, aspen, alder, cottonwood and willow trees, but such orchard trees as apple, pear, prune and the like, as may lie within Transition areas. In winter at lower levels it gives attention to evergreen trees, white birch, mountain ash, peach, plum, apricot, English walnut, elder, and pepper trees. * * * Instead of gleaning at random, as we might expect, the Sapsucker makes careful selection, like a prudent forester, of a single tree, and confines his attentions henceforth, even though it be through succeeding seasons, to that one tree. Starting well toward the top of an evergreen, or well up on the major branches of an orchard tree, the bird works successively downward in perpendicular rows, whose borings are sometimes confluent. In this way the bird secures an ever-fresh flow of sap, from below. If carried on too extensively, or persisted in for successive seasons, these operations will sometimes cause a tree to bleed fatally, or at least to fall easy victim to insect pests. I have myself seen limbs of mountain ash trees, pear trees, and English walnut, done to death in this fashion. Yet it is only fair to say that but one or two trees in an orchard may be attacked, and there is scarcely more danger of the trouble spreading than there would be from successive strokes of lightning. * * *
For the rest, Sphyrapicus ruber is a large consumer of ants, and does some good in the destruction of leaf-eating beetles. Berries of the pepper trees (Schinus molle) are eaten to some extent, in winter, as are also, regrettably, seeds of the poison oak.
W. Otto Emerson (1893) says: “One I watched every morning from my tent fly to the top of a tall burnt tree and rap its roll-call as a kind of warning may be to the flying insects. It would then sail out like a flycatcher, catch an insect, and return to the burnt tree-top. Its movements were very graceful and regular. As it dipped or circled around for this or that insect the sunlight catching on the red breast lit it up like a patch of flame.” He says elsewhere (1899): “One I found in a willow tree trying to get the best of a yellow jacket’s nest, dodging back and forth either to get a mouthful of their stored sweets or the jackets themselves.”
Junius Henderson (1927) gives, in his table, the percentages of animal and vegetable food, exclusive of sap, taken by this sapsucker. Based on a study of 34 stomachs the total animal food made up 69 percent and the total vegetable food 31 percent of the whole; 42 percent consisted of ants and 12 percent of fruits, mostly wild; insects accounted for 11 percent and seeds for 5 percent.
Behavior.—Grinnell and Storer (1924) write:
The Sierra red-breasted sapsucker is in our experience well-nigh voiceless and its work is done in such a quiet manner that it does not ordinarily attract attention, as do the woodpeckers that are wont to pound noisily. The most vigorous drilling of the sapsucker will scarcely be heard more than a hundred feet away. The bird moves its head through a short arc, an inch or two at the most, giving but slight momentum to the blows. The chips cut away are correspondingly small, mere sawdust as compared with the splinters or slabs chiseled off by other woodpeckers. The strokes are delivered in intermittent series, four or five within a second, then a pause of equal duration, then another short series, and so on. From time to time a longer pause ensues, when the sapsucker withdraws its bill and gazes monocularly at the work.
Mr. Skinner says, in his notes: “Although methodical, these birds seem quite nervous, moving from stem to stem. Generally they perch lengthwise of a limb when working or feeding but are apt to perch crosswise when hopping from limb to limb. After a sapsucker has its wells established, it finds it necessary to stay near to guard them from other birds attracted by the sap, or by the insects drawn there. Preening is often done while guarding the wells. The hairy woodpeckers chase these sapsuckers from tree to tree. The Audubon and lutescent warblers literally swarm to the sap-wells in the willows whenever the sapsuckers cease to guard them, but I do not know that there is active antagonism between the species. On one occasion, I saw a young sapsucker chase off a chipmunk that came too near.”
Voice.—Ralph Hoffmann (1927) says that “the ordinary cry is a nasal squeal, chée-arr, somewhat suggesting the note of a red-bellied hawk.” But it is apparently not a noisy bird, as Grinnell and Storer (1924) say that it is “well-nigh voiceless”.