National Geographic : 1933 Jul
EAGLES, HAWKS, AND VULTURES PRAIRIE FALCON (Falco mexicanus) This pale-colored falcon has the active, graceful flight of the duck hawk. In a way, it is the arid country representative of that species, but may be distinguished from it by smaller size and paler, sandy coloration. The nest is placed on a cliff, being often in a recess or small cave, where the eggs are laid on the bare surface, with only whatever rubbish may have accumulated for nesting material. Two to five consti tute a complete set, three or four being the customary complement. The ground color of the eggs is creamy white, more or less overlaid with a suffusion of cinnamon, and blotches of reddish brown and chocolate. They are considerably paler than the eggs of the duck hawk. The prairie falcon feeds on birds of various kinds, blackbirds, horned larks, mourning doves, and others of similar size being favorites. It captures quail and prairie chickens on occasion, and also se cures domestic pigeons where flocks of these are found within its range. I have seen them harry colonies of yel low-headed blackbirds so mercilessly that these unfortunates set up a loud outcry whenever a falcon appeared in the dis tance. The prairie falcon also feeds on mammals, taking gophers, ground squir rels, and various kinds of rats and mice. In addition, it takes insects, particularly grasshoppers when these are abundant. In feeding, these hawks sometimes watch from cliffs or open perches in trees until suitable prey appears, or again fly lightly and gracefully along, traveling rather swiftly as they hunt. They have been known to harry marsh hawks and make these birds drop their prey. The falcon seizes its booty in the air as it falls. About their nesting cliffs these falcons are quite noisy, uttering shrill screams and cackling calls when disturbed. At other seasons they are mainly silent. The prairie falcon nests from southern British Columbia to Baja California and southern Mexico, extending east to the eastern border of the Great Plains. It is casual in occurrence in Manitoba, Minne sota, and Illinois. A related species is found in the South west, the aplomado falcon (Falco fusco coerulescensseptentrionalis). AUDUBON'S CARACARA (Polyboruscheriway auduboni) Although related to the falcons, this peculiar species, often called "Mexican eagle," has many of the habits and man nerisms of vultures. It is found in prairie regions where there are open groves, pre ferring open country to heavily forested sections. Its flight is straight and rapid, and it sometimes circles high in the air, especially on days of oppressive heat. In Florida these birds frequently nest in cabbage palmettos; in Texas they oc cupy mesquites and other trees, and in Arizona giant cacti are sometimes selected. The nests are bulky masses of twigs, weeds, coarse grass, leaves, and Spanish moss, usually piled together in an untidy manner. The eggs number two or three, the ground color being creamy white when it is visible. Most eggs have the entire surface obscured by a wash of cinnamon rufous and blotches of reddish brown. This bird eats lizards, snakes, frogs, and small turtles, and also takes small mam mals. It is fond of rabbits, cotton rats and other mice, and grasshoppers and other large insects. Crabs and crayfish, too, are on its bill of fare. The caracara is also partial to carrion of all kinds, and frequently comes to car casses on which vultures are feeding. The caracaras make the larger birds stand aside, as they are strong and aggressive, striking with both bill and feet. On the coast of Texas caracaras have been seen in pursuit of brown pelicans to make them disgorge fish that they had swallowed. Caracaras are active on the ground, their long legs and relatively short claws en abling them to walk and run with ease. Their voices are peculiar rattling, creak ing, screaming calls, in uttering which the birds frequently throw the head backward until it touches the back. On Guadalupe Island, Mexico, off the western coast of Baja California, there was formerly found the Guadalupe cara cara, Polyborus lutosus. The last of this species was recorded about 1905. Audubon's caracara nests from north ern Baja California, southwestern Ari zona, central and southern Florida, and Cuba south through Mexico and Central America. It has been recorded acciden tally in Ontario. An allied race occurs in northern South America.