Habitat, Maldonado, La Plata, (July.)
This hawk was not uncommon on the grassy savannahs and hills in the neighbourhood of the Rio Plata. Mr. Gould remarks “that in size it fully equals the Circus æruginosus of Europe, which it doubtless represents in the countries it inhabits. This species has a remarkable specific character in the lanceolate and conspicuous stripes down its breast.”
2. Circus cinerius. Vieill.
Circus cinerius, Vieill. Ency. Meth.
Falco histrionicus, Quoy and Gaim. Voy. autour du monde, Plate 15.
Circus histrionicus, Vigors, Zoological Journal, vol. iii. p. 425, note.
My specimens were obtained at the Falkland Islands, and at Concepçion in Chile. M. D’Orbigny states that it is a wild bird; but at the Falkland Islands it was, for one of its order, very tame. The same author gives a curious account of its habits: in a different manner from other raptorial birds, when it has killed its prey, it does not fly to a neighbouring tree, but devours it on the spot. It roosts on the ground, either on the top of a sand hillock, or by the bank of a stream: it sometimes walks, instead of hopping, and when doing so, it has some resemblance in general habit to the Milvago chimango. It preys on small quadrupeds, molluscous animals, and even insects; and I find in my notes, that I saw one in the Falkland Islands, feeding on the carrion of a dead cow. Although in these respects this Circus manifests some relation in its habits with the Polyborinæ, yet it has the elegant and soaring flight, peculiar to its family; and in form it does not depart from the typical structure. Mr. Gould remarks that “we see in this elegant bird as perfect an analogue of the Circus cyaneus of Europe, as in the preceding species of the Circus æruginosus.”