Buteo elegans.
In regard to its distinctive specific habits but little is as yet known, but it is probable they are not essentially different from those of the lineatus, Dr. Cooper bearing positive testimony to this fact. He found this Hawk common in the southern part of the State, especially near San Diego, but he did not meet with any in the Colorado Valley. On his approach to one of them, it would always fly off from its usual perch, circling up high into the air, and uttering short shrill screams in rapid succession in the manner of the lineatus. He noticed a pair constantly at one place near a ranch, and supposed they were about building there, but was not able to find the nest.
Among the memoranda of Mr. Xantus, made at Fort Tejon, Cal., is one dated May 9, mentioning the finding the nest of this species. It contained four eggs, was built in an old decayed tree, in a swamp, and was about fifteen feet from the ground. The nest was large and made of sticks.
Buteo borealis (Gmel.).
RED-TAILED HAWK.
Sp. Char. Form heavy and robust; wings moderate, the third to fifth quill longest; the first shorter than the seventh; outer four with inner webs cut. Feet strong, the tarsi and toes robust, and claws not very acute. Dimensions: Wing, 13.50–17.25; tail, 8.50–11.30; culmen, .90–1.15; tarsus, 2.70–3.40; middle toe, 1.60–1.95; weight, 2½ to 4 lbs. Colors: Adult: tail, deep lateritious-rufous, paler at the tip, and usually with a subterminal bar of black (sometimes without any bar, and sometimes with numerous bars to the base). Above blackish-brown, more or less variegated with whitish on the scapulars and wing-coverts; beneath white, usually with a belt of blackish spots across the abdomen; sometimes wholly dusky or blackish beneath, but the pectoral region always appreciably lighter than the abdomen; under surface of primaries plain white anterior to their emargination. Young. Tail grayish-brown, with nine or ten narrow, sharply defined bands of blackish. Pattern of other parts as in the adult, but the white purer, and the plumage generally with less rufous.
Hab. Entire continent of North America; West Indies.
The plumage varies from wholly dusky blackish, with a paler, more brownish, pectoral area, and the tail of the adult with numerous black bars, or indications of bars, to the very base (var. calurus), through various proportionate degrees of rufous and dusky, to entirely pure white beneath, without any spotting; the tail of the adult without a single black bar (vars. krideri and lucasanus).
Var. borealis, Gmelin.
EASTERN RED-TAIL.
Falco borealis, Gmel. Syst. Nat. p. 266, 1789.—Lath. Ind. Orn. p. 25, 1790; Syn. I, p. 50, 1780; Supp. II, 34, 1787; Gen. Hist. I, p. 265, 1821.—Daud. Tr. Orn. II, 157, 1800.—Shaw, Zoöl. VII, 112, 1812.—Wils. Am. Orn. pl. lii, fig. 1, 1808.—Sab. Frankl. Exp. p. 670.—Wagl. Isis, p. 517, 1831.—Bonap. Ann. N. Y. Lyc. II, pp. 32, 434; Isis, p. 1138, 1832.—Aud. Birds Am. pl. li, 1831; Orn. Biog. I, p. 265, 1831; Syn. VI.—Gray, Genera, 1840.—Rich. F. B. A. II, 50, 1831.—Nutt. Man. I, 102, 1840.—Gosse, Birds Jam. II, 1847.—Dough. Cab. I, 229, pl. xxx, 1830. Buteo borealis, Vieill. Nouv. Dict. Hist. Nat. IV, p. 478, 1819; Enc. Méth. III, p. 1222, 1823.—Vig. Zoöl. Journ. I, p. 340; Zoöl. Beech. Voy. p. 15.—Steph. Zoöl. XIII, pt. 2, p. 47, 1826.—Less. Tr. Orn. p. 79, 1831.—James. (Wils.) Am. Orn. I, pp. 82, 84, 1808.—Jard. (Wils.) Am. Orn. II, pp. 280, 282, 1808.—Brew. (Wils.) Am. Orn. p. 450; Synop. p. 684.—Bonap. Eur. & N. Am. B. p. 3, 1838; Consp. Av. p. 19.—Aud. Synop. p. 6, 1839.—Gray, Gen. B. fol. sp. 6, 1844; List B. Brit. Mus. p. 34, 1844.—Pucher. Rev. Zoöl. p. 214, 1850.—Gosse, B. Jam. p. 11, pl. ii, 1847.—Cass. B. Cal. & Tex. Syn. p. 97, 1854; Proc. Ac. Sc. Philad. p. 279, 1855.—Gamb. Journ. Ac. Nat. Sc. Phil. N. S. I, p. 26.—Nutt. Man. Orn. U. S. & Canad. p. 102, 1833.—De Kay, Zoöl. N. Y. II, p. 9, pl. viii, f. 17 (Juv.), 1844.—Peab. Bost. Journ. Nat. Hist. III, p. 80, 1837.—Thomp. Hist. Verm. App. p. 63, 1853.—Peale, U. S. Expl. Exp. p. 62, 1848.—Towns. Sit. Exp. Zuñi & Color. p. 59.—Kaup, Ueb. Falk. Mus. Senck. p. 261, 1845.—Strickl. Orn. Syn. I, 29, 1855.—Max. Cab. Journ. VI, 1858, 17.—Blakist. Ibis, III, 1861, 318.—Wood, Am. Nat. III, 1869, 393.—Gray, Hand List, I, 1869, 7. Astur borealis, Cuv. Règ. An. (ed. 2), I, 332, 1829.—Swains. Class. B. I, 316; II, 215, 1837, Pœcilopternis borealis, Kaup, Isis, Mon. Falc. Cont. Orn. 1850, p. 76. Falco leverianus, Gmel. Syst. Nat. 266, 1789.—Lath. Ind. Orn. p. 181, 1790; Syn. Supp. I, 31, 1787; Gen. Hist. I, 620, 1821.—Daud. Tr. Orn. II, 126, 1800.—Shaw, Zoöl. VII, 151, 1812.—Wils. Am. Orn. pl. lii (Juv.), 1808.—Aud. Orn. Biog. I, 265. Buteo leverianus, Vig. Zoöl. Journ. I, 340.—Steph. Zoöl. XIII, pt. 2, p. 47, 1815. Falco aquilinus, Bartr. Tran. p. 390, 1791. Accipiter ruficaudus, Vieill. Ois. Am. Sept. pl. xiv, bis. 1807. Buteo fulvus, Vieill. Ois. Am. Sept. p. 34; Nouv. Dict. Hist. IV, p. 468 (quot. F. jamaicensis), 1819. Buteo ferrugineocaudus, Vieill. Ois. Am. Sept. pl. vi, 1807.—Cuv. Règ. An. (ed. 2), I, 337. Buteo americanus, Vieill. Nouv. Dict. Nat. IV, 477 (quot.), Ois. Am. Merid. pl. vi, Enc. Méth. III, 1224, 1823. ? Buteo gallinivorus, Vieill. Ois. Buteo borealis, Brewer, N. A. Oölogy, 1857.