In this Finch the plumage is alike in both sexes. Above it is dusky olive-green, beneath grey; the beak is of a fine bright red. In Argentina this bird is most common in the littoral forests along the Plata, but ranges as far south as the Rio Negro in Patagonia. It does not migrate, nor associates in flocks; but the sexes are faithful, and the male and female are invariably together, and appear to be very fond of each other’s society. They have a loud, sharp alarm chirp or cry, which bursts from the bird with the startling suddenness of a sneeze from a human being; also a confused unmelodious song, which always reminds me, in its hurry, vehemence, and peculiar sound, of the gobbling of a turkey-cock. They are not shy, but when approached sit jerking their tails about, and uttering loud chirps as if greatly excited. The flight is very curious; the bird springs up with great suddenness, and with tail erect, and the long legs dangling down like a Rail’s, proceeds by a series of irregular jerks, violently shutting and opening its wings. They breed on the ground under the grass, and conceal their nest so well that I doubt whether the parasitical Molothrus ever finds it. I have, at all events, never seen them followed by the young of Molothrus demanding food.
As a rule, small seed-eating birds are beneficially affected by the presence of man; thus our common Zonotrichia and other sparrows and finches have become excessively numerous in the most thickly-settled districts. With the Red-billed Finch, however, just the contrary has happened; and since I have known this species it has disappeared from many localities where it was once quite common. Azara’s name for this species, Habia de bañado, signifies that it is a marsh bird; but though now found chiefly in marshy situations, it was once common enough over the entire pampas region, before the great plains were settled on by Europeans. The bird is very badly protected by nature against raptorial species, owing to its very conspicuous red beak, its habit of perching on the summit of tall plants and other elevated positions, its loud impetuous voice, which invites attention, and the weak eccentric flight, which challenges pursuit. It is essential to its safety that it should have, in the open country it frequents, a dense grass cover into which it can plunge on the slightest alarm. Where cattle are introduced, the original pampas-grass, which afforded the suitable conditions, disappears, giving place to the soft, perishable grasses, clovers, and thistles of Europe. Where these changes take place, the bird cannot escape from its enemies and quickly disappears; while many Dendrocolaptine species inhabiting the same situations are saved by their inconspicuous protective colouring, sharp wedge-like bodies, and swift mouse-like motions on the ground. In marshy places on the pampas, abounding with long aquatic grasses and reed-beds, the Red-bill still maintains its existence, but from its old habitat on the open grassy plains, where it was once the dominant Finch, it has utterly vanished.
[84.] EMBERNAGRA OLIVASCENS (d’Orb. et Lafr.).
(OLIVE GROUND-FINCH.)
Embernagra olivascens, d’Orb. Voy., Ois. p. 285; Burm. La-Plata Reise, ii. p. 485 (Mendoza); Scl. et Salv. Nomencl. p. 32; Salvin, Ibis, 1880, p. 355; Döring, Exp. al Rio Negro, Zool. p. 40 (R. Colorado).
Description.—Similar to Embernagra platensis, but the back unstriped, and the olive hue somewhat purer; also the abdomen of a paler buff: total length 8·1 inches, wing 3·7, tail 4·0. Female similar.
Hab. Bolivia, Western Argentina, and Patagonia.
This species, which was met with by Dr. Burmeister near Mendoza, was found by Dr. Döring as far south as the Rio Colorado, on the pampas.