Part 43

This well-marked genus contains but a single species, the P. tharus, Mol., which extends its range over the whole of tropical and subtropical America, exclusive of some of the West India Islands. North and south of the Isthmus it is modified into geographical races, the southern of which is var. tharus, Mol., and the northern var. auduboni, Cass.

The closely related genera Phalcobænas, Milvago, Ibycter, and Daptrius are peculiar to South America and the southern portion of Middle America, most of them being represented by two or more species. They all form a well-marked and peculiarly American group, for which I shall retain Schlegel’s term Polybori.

Their habits are quite different in many respects from those of other Falconidæ, for they combine in many respects the habits of the gallinaceous birds and those of the Vultures. They are terrestrial, running and walking gracefully, with the exception of the species of Ibycter and Daptrius, which are more arboreal than the others, and are said also to feed chiefly upon insects, instead of carrion.

Species and Races.

=P. tharus.= Wing, 14.50–17.70; tail, 10.00–11.00; culmen, 1.20–1.48; tarsus, 3.20–4.20; middle toe, 1.75–2.30.

Adult. Forehead, crown, occiput, back, rump, abdomen, sides, and tibiæ, and terminal zone of the tail, dull black. Neck, breast, tail-coverts, and tail, dingy whitish. Interscapulars, breast, and tail with transverse dusky bars.

Young. Blackish areas replaced by dull brown; region of the transverse bars marked, instead, with longitudinal stripes.

Adult. Whole body, with middle wing-coverts, variegated with transverse bars of black and white; tail-coverts barred. Terminal zone of the tail about 2.00 wide. Young. Longitudinal stripes over the whole head and body, except throat, cheeks, and tail-coverts; tail-coverts transversely barred. Hab. South America …

var. tharus.

Adult. Transverse bars confined to the breast and interscapulars; rest of body continuous black; tail-coverts without bars; wing-coverts unvariegated. Terminal zone of tail about 2.50 wide. Young. Longitudinal stripes confined to the breast and interscapulars; rest of the body continuous brown. Tail-coverts without bars. Hab. Middle America, and southern border of United States, from Florida to Cape St. Lucas …

var. auduboni.

Polyborus tharus, var. auduboni, CASSIN.

CARACARA EAGLE; “KING BUZZARD” OF FLORIDA.

Polyborus auduboni, CASSIN, Proc. Acad. Nat. Sc. Philad. 1865, p. 2. Polyborus vulgaris (“VIEILL.”), AUD. Orn. Biog. II, 350, 1834 (not of VIEILLOT!). Polyborus brasiliensis (“GMEL.”), AUD. Birds Am. Oct. ed. I, 21, 1840 (not of GMELIN!). Polyborus tharus (“MOL.”) CASSIN, Birds of Cal. & Tex. I, 113; 1854 (not of MOLINA!); BREWER, Oölogy, 1857, p. 58, pl. xi, figs. 18 & 19; BAIRD, Birds N. Am. 1858, p. 45.—HEERM. P. R. R. Rept. VII, 31, 1857.—COUES, Prod. Orn. Ariz. p. 13, 1866.—OWEN, Ibis, III, 67.—GURNEY, Cat. Rapt. B. 1864, 17.—DRESSER, Ibis, 1865, 329 (Texas).

SP. CHAR. Adult male (12,016, Texas; Capt. McCall). Forehead, crown, occiput, and nape, wings, scapulars, rump, belly, thighs, and anal region continuous deep dull black; chin, neck, jugulum, breast, and tail-coverts (upper and lower), soiled white. Breast with numerous cordate spots of black, these growing larger posteriorly, and running in transverse series; back with transverse bars of white, which become narrower and less distinct posteriorly. Basal two-thirds of tail white, crossed by thirteen or fourteen narrow transverse bands of black, which become narrower and more faint basally; outer web of lateral feather almost entirely black; broad terminal band of the tail uniform black (2.40 inches in width); third, fourth, fifth, and sixth primaries grayish just beyond the coverts, this portion with three or four transverse bars of white. Middle portion of primaries beneath, faintly barred with white and ashy; the barred portion extending obliquely across. Third quill longest, fourth a little shorter, second shorter than fifth; first 3.60 inches shorter than longest. Wing, 16.70; tail, 9.60; tarsus, 3.40; middle toe, 2.10.

Adult female. Plumage similar; white more brownish; abdomen with indication of bars. Wing, 15.50; tail, 8.70; tarsus, 3.30; middle toe, 2.20.

Young (42,130, ♀, Mirador, Mexico; Dr. C. Sartorius). Black of adult replaced by dingy dark brown, this darkest in the hood; white and dusky regions gradually blended, the feathers of the breast being whitish, edged (longitudinally) with brown. No trace of the transverse bars, except on the tail, which is like that of the adult.

HAB. Middle America north of Darien; southern border of United States from Florida to Lower California; Cuba.

Localities: Guatemala (SCL. Ibis, I, 214); Cuba (CAB. Journ. II, lxxix; GUNDL. Rept. 1865, 221, resident); ? Trinidad (TAYLOR, Ibis, 1864, 79); Texas (DRESSER, Ibis, 1865, 329, breeds); Arizona (COUES); Costa Rica (LAWR. IX, 132); Yucatan (LAWR. 16, 207.)

LIST OF SPECIMENS EXAMINED.

National Museum, 16; Boston Society, 2; Philadelphia Academy, 4; Museum Comp. Zoöl., 1; R. Ridgway, 2. Total, 25.

Measurements.

+----+-----------+-----------+---------+---------+-----------+----------+ |Sex.| Wing. | Tail. | Culmen. | Tarsus. |Middle Toe.|Specimens.| +----+-----------+-----------+---------+---------+-----------+----------+ | ♂ |14.60–16.50| 9.00–10.00|1.20–1.48|3.20–3.60| 1.90–2.00| 6 | +----+-----------+-----------+---------+---------+-----------+----------+ | ♀ |14.75–16.00| 8.80–10.00|1.20–1.45|3.55–3.75| 2.00–2.10| 8 | +----+-----------+-----------+---------+---------+-----------+----------+

HABITS. The Caracara Eagle, as this bird is called, though it seems to possess, to a large degree, the characteristics of a Vulture, and hardly any of the true aquiline nature, is found in all the extreme southern portions of the country, in Florida, Texas, Southern Arizona, and California. Audubon met with it abundantly in Florida in the winter of 1831. Mr. Boardman has seen it quite common at Enterprise, associating with the Vultures. Dr. Woodhouse, while encamped on the Rio Saltado, near San Antonio, in Texas, frequently saw the Caracaras, and always in company with the Vultures, which he says they greatly resemble in their habits, excepting that they were much more shy. He could, however, readily approach them when on horseback. Mr. Dresser also frequently encountered it in Texas in the vicinity of San Antonio, and speaks of it as abundant from the Rio Grande to the Guadaloupe, but never noticed any farther east. In Arizona, Dr. Coues says, it is not a rare bird in the southern and western portions of that Territory. Lieutenant Couch likewise describes them as exceedingly abundant from the Rio Grande to the Sierra Madre. He speaks of killing a male bird on the nest, which was in a low tree and composed of sticks. He adds that this bird destroys the Texas field-rats (Sigmodon berlandieri) in large numbers.

Dr. Heermann met with this species on the Colorado River, near Fort Yuma, in company with the Cathartes aura. He found it so shy that it was impossible to procure a specimen. He found it along the Gila River, and again met with it in Texas wherever there were settlements. At San Antonio, wherever there were slaughter-houses, he met with them in great numbers, twenty or thirty being often seen at a time.

Grayson gives the Caracara as quite abundant in the Tres Marias. Although it subsists mainly on dead animals and other offal, it is said to sometimes capture young birds, lizards, snakes, and land-crabs. It generally carries its prey in its beak; but Colonel Grayson states that he has seen it also bear off its food in its claws, as Hawks do. It walks with facility on the ground, and was often met with in the thick woods, walking about in search of snakes. Mr. Xantus found it nesting at Cape San Lucas, placing its nest on the top of the Cereus giganteus. It occurs also in the West Indies, especially in the island of Cuba, where it is known to breed. Eggs were obtained and identified by the late Dr. Berlandier, of Matamoras, in Northern Mexico, on the Rio Grande, in considerable numbers.

Mr. Salvin (Ibis, I, 214) says the Caracara is universal in its distribution in Central America, appearing equally abundant everywhere. At Duenas it was a constant resident, breeding on the surrounding hills. Its food seemed to consist largely of the ticks that infested the animals. In Honduras Mr. G. C. Taylor found them very common, quite tame, and easily shot. They feed on carrion and offal, were often seen scratching among the half-dry cow-dung, and are “a very low caste bird.” Mr. E. C. Taylor (Ibis, VI, 79) frequently saw this bird on the shores of the Orinoco. It was very tame, and generally allowed a near approach, and when disturbed did not fly far. He did not meet with it in Trinidad.

On the Rio Grande the popular name of this species is Totache, while in Chile the P. tharus is called Traro, but its more common name throughout South America is Carrancha.