National Geographic : 1933 Jul
THE NATIONAL GEOGRAPHIC MAGAZINE SHARP-SHINNED HAWK (Accipiter velox velox) This small hawk, one of the most widely distributed of the group in North Amer ica, is an inhabitant of thickets and wood land. It may be readily identified by its short wings and long tail, the square end of the latter distinguishing it from the larger Cooper's hawk. Though fiercely preda tory, flying swiftly in pursuit of prey, this bird spends long periods in resting quietly in trees or bushes. As it usually perches among limbs or leaves, it is often overlooked until it flies. The sharp-shin feeds almost entirely on birds and is highly destructive. Although it preys mainly on small species, such as sparrows, warblers, and similar forms, it does not hesitate to attack birds as large as itself, regularly killing quail, mourning doves, and flickers. In southward migration in fall, these hawks often follow definite lines of flight, so that thousands may pass leisurely by certain points in the course of a few days. Sometimes during these flights stuffed owls are used as decoys to attract the hawks, so that they may be shot. The sharp-shinned hawk makes a bulky nest of twigs, sometimes without an inner lining, but often with a slight padding of soft bark or a few feathers. The nest is frequently placed in pines or spruces against the trunk of a projecting limb from 20 to 50 or more feet from the ground. SHARP-SHINNED HAWKS WILL FIGHT FIERCELY FOR THEIR NESTS Three to five eggs usually make a set, though as many as seven have been found in one nest. The ground color is pale bluish or greenish white, blotched and marbled with brown and lavender. The sharp-shin is bold in defense of its nest and I have had one strike fiercely at me, re turning with chattering calls to the attack time after time. The immature sharp-shin has the under parts longitudinally streaked with dusky. The female is much larger than the male. This species breeds throughout most of the United States and Canada from the northern limit of trees south to Florida, Texas, and south-central California. In winter it is found from British Columbia and the northern United States south to Panama. Allied races are found in the Greater Antilles. COOPER'S HAWK (Accipiter cooperi) This hawk, in appearance and habits, is a large edition of the sharp-shin. Since the sexes differ markedly in size, the fe male being much larger, a small male Cooper's hawk is about the size of a large female sharp-shin, the rounded instead of the square-ended tail offering the most evi dent character for distinguishing between the two. The Cooper's hawk is the ogre in the world of our birds. Fierce and ruthless, it attacks grouse or other species as large as itself, and destroys smaller birds without the slightest difficulty. It darts through thickets with such ease that it is difficult for its victims to find cover for safe sanctuary. Rabbits and other small mammals, reptiles, and insects are eaten occasionally. The bird is bold and fearless in pursuit of its quarry, and has been known to re turn several times to attack a chicken, even when people were present and threatening it. It is one of the hawks that merits the name of "chicken hawk" and must be con sidered entirely destructive. Indeed, it is responsible for much of the damage in the hen-yard for which its larger relatives that live more in the open get the blame. It is also a consistent enemy of ruffed grouse and quail. This species often follows the lines of fall migration frequented by the sharp shin, but is less abundant; so that it is killed by hunters along these flyways in smaller numbers. Cooper's hawks may appropriate the last year's nests of crows or other hawks, or may build a new structure. In either case the nests are composed of coarse twigs lined with finer material of the same kind, the whole frequently mixed with frag ments of bark. The eggs range from three to five in number, with the ground bluish white or greenish white, sometimes plain, but more often spotted with brown. In the nesting season the Cooper's hawk is quite noisy, uttering loud, harsh notes that are rapidly repeated. The immature bird is streaked underneath with dusty. The Cooper's hawk -nests from south ern British Columbia, southern Quebec and Nova Scotia south through the United States into northern Mexico. In winter it is found south into Costa Rica.