I was camping in a pine forest not many miles from Reserve, N. Mex., accompanied by a small English terrier. In front of my tent stood a large dead pine, near the top of which there were a number of holes, evidently the homes of four pairs of Ant-eating Woodpeckers (Balanosphyra formicivora aculeata). A gray tassel-eared squirrel came scampering along, and was at once spied by the dog, which gave chase. The squirrel ran up the dead tree mentioned above, to be instantly assailed by the woodpeckers. Their constant cries and their sharp bills made things so uncomfortable for the squirrel that it ran down the tree to within a few feet of the dog, who sent him scampering to the top again with his eight antagonists constantly flaying him.
About this time there was a swish of wings, and a sharp-shinned hawk (Accipiter velow) darted like a streak among the woodpeckers. For an instant it seemed that one of them was doomed, but by a small margin it managed to escape, and in an instant they had all darted to cover among the green boughs of surrounding trees. All was quiet for a few brief seconds, when the woodpeckers returned to the attack, except one which perched on the topmost bough of a near-by tree, as guard or lookout, watching for the hawk. The other seven took up the fight with the squirrel.
In a few minutes the hawk again appeared on the scene, the guard gave a shrill call of warning, and all the woodpeckers were under cover before their enemy could reach them. The hawk, then, finding the birds on their guard, left and did not return. The terrier soon abandoned the tree, and the squirrel hurried down and scampered away; the woodpeckers quickly quieted down and went peacefully about their home affairs. I believe that the birds recognized in the squirrel a danger to their eggs or young.
BALANOSPHYRA FORMICIVORA MARTIRENSIS Grinnell and Swarth
SAN PEDRO WOODPECKER
HABITS
The acorn-storing woodpecker of the Sierra San Pedro Martir, northwestern Baja California, has been separated and described by Grinnell and Swarth (1926) under the above name, to which they have added the long common name “San Pedro Martir acorn-storing woodpecker.” Its distinguishing characters are given as follows:
Most nearly like B. f. bairdi. Distinguished from that species primarily by shorter wing, and by slightly shorter and notably weaker, more slender bill; also by average differences in head markings as set forth below. * * *
The relatively feeble bill of this bird, as compared with that of the upper California bairdi, is the most conspicuous character of this subspecies. In bill structure it is closely similar to B. f. aculeata, of Arizona.
The character of the head markings in the female is suggestive again of aculeata, the red area being usually more nearly square, as in that form, rather than shorter than wide, as in bairdi. The white frontal band averages slightly narrower than in bairdi, an approach toward the condition in angustifrons, of the Cape San Lucas region. The yellowish white (more dilutely yellow than in bairdi) U-mark on the lower throat in both sexes averages very much narrower in our specimens of martirensis than in a large series of bairdi usually only about half the width of the former as in the latter. This we are not quite confident of as a real character, in that there is a chance that “make” of specimen (whether or not the skin of the throat was stretched) affects the width of the white band. * * *