No. 41,759 (immature), Merida, Yucatan (Dr. Schott), is remarkably light colored, or, rather, is unusually variegated with whitish above; the tail, also, is almost white; the bands, however, very conspicuous. The lower parts are as thickly spotted as in specimens from Washington Territory.
The young bird of this western style is as different from that of the eastern as is the adult, and the essential differences are about the same,—i.e. darker colors, or a predominance, or, rather, increase in size, of the dark markings. The numerous heavy transverse spots on the tibia constitute a persistent feature of the young of the var. calurus, as compared with the almost, or perfectly, immaculate white of those in var. borealis.
It being certain that the Buteo montanus of Nuttall is really the B. swainsoni, and not the variety of borealis so called by Mr. Cassin, it becomes necessary to drop this name in connection with the present bird, and transfer it as a synonyme to swainsoni. In its place, Mr. Cassin’s name calurus must be substituted, under which was described the melanistic condition of the present variety of borealis.
In describing his B. montanus, Nuttall cites Audubon’s plate of “Falco buteo,” which, of course, is a name by which the B. swainsoni was first designated before it was distinguished from the B. vulgaris of Europe. Audubon’s plate represents, unmistakably, the adult female of the Buteo swainsoni.
Habits. The well-known Red-tailed Hawk is widely distributed throughout North America from the West Indies and Central America to the Arctic regions, and from the Atlantic to the Pacific.
According to Sir John Richardson, it is common in the fur countries, which it visits in summer, and where a few are known to breed. Specimens were taken by his party on the Rocky Mountains, the plains of the Saskatchewan, and at the York factory. These were all between the 53d and the 57th parallels of latitude.
Buteo borealis (adult).
Mr. Salvin cites it as generally and plentifully distributed throughout Guatemala, from whence numerous examples in all stages of plumage, from the young to the adult, were transmitted by Mr. Skinner. It was also found at Dueñas by him. Mr. Swainson states that this Hawk was taken on the plains of Mexico by Mr. Taylor. A single specimen was received by Mr. Lawrence from Panama. Mr. Gosse states that it is the most common bird of this family in Jamaica, where it is a resident, and where it breeds. Mr. Lembeye and Dr. Gundlach both include it in their lists of the birds of Cuba, and the latter marks it as breeding in that island. It has been observed in Florida by Mr. Allen, and is not uncommon in all the New England States, where it is resident throughout the year. In the Southern States it is most abundant in the winter months.