Argentine Ornithology - Volume Ii Part 17
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Volume Ii Part 17

They are slightly larger than those of the Turkey-Buzzard, although the latter is a bigger bird. The ground-colour is of a yellowish white, with blotches of dark reddish brown, and smaller markings of a lilac shade.

These markings are generally more numerous at the larger end."

313. SARCORHAMPHUS GRYPHUS (Linn.).

(GREAT CONDOR.)

+Sarcorhamphus gryphus+, _Darwin, Zool. Beagle_, iii. p. 1 (Rio Negro); _Scl. et Salv. Nomencl._ p. 123; _Burm. La-Plata Reise_, ii. p. 433 (Cordova); _Durnford, Ibis_, 1877, p. 40 (Chupat), et 1878, p. 398 (Central Patagonia).

_Description._--General plumage glossy black; greater wing-coverts margined with ashy; neck-ruff white; head, neck, and centre of chest bare; head, with a large caruncle, black; throat wattled; chest with a pendent wattle: whole length 380 inches, wing 290, tail 140.

_Female_ similar, but without the wattles on the head and neck.

_Hab._ Andes of South America, and adjacent ranges in La Plata.

Dr. Burmeister tells us that he has seen the Condor in the Sierras of Cordova and Aconquija, though it is more prevalent in the districts of the Western Cordillera.

In the territory of Chupat, Durnford met with it at Ninfas Point in November, and tells us that when the colonists are hunting in the neighbourhood of the sea-coast the Condor is the first of the bird-scavengers to make its appearance after game has been killed.

During his subsequent excursion to the Sengel river in the interior, the Condor was commonly observed throughout the journey wherever the rocks were high and steep. Several pairs were noticed nesting on Nov. 16th, but the nests could not be reached.

My own experience of the Condor is restricted in seeing one individual, flying above the sea-sh.o.r.e, south of the Rio Negro.

Order VIII. STEGANOPODES.

Fam. x.x.xIV. PHALACROCORACIDae, or CORMORANTS.

The only family of the Steganopodes that can at present be inserted in the Argentine list is that of the Cormorants, though doubtless other forms of this Order (_Sula_, _Phaethon_, and _Fregata_) will be hereafter found to occur on the coast with more or less frequency.

One Cormorant only has yet been positively determined as occurring within the Argentina area.

314. PHALACROCORAX BRASILIa.n.u.s (Gm.).

(BRAZILIAN CORMORANT.)

+Phalacrocorax brasilia.n.u.s+, _Scl. et Salv. Nomencl._ p. 124; _iid.

P. Z. S._ 1868, p. 146 (Buenos Ayres); _Durnford, Ibis_, 1877, p.

188 (Buenos Ayres), et 1878, p. 399 (Patagonia); _White, P. Z.

S._ 1882, p. 624 (Buenos Ayres); _Barrows, Auk_, 1884, p. 270 (Entrerios). +Haliaeus brasilia.n.u.s+, _Burm. Syst. Ueb._ iii. p.

460; _id. La-Plata Reise_, ii. p. 520 (Rio Parana).

_Description._--Black; feathers edged with metallic green; bill and naked skin of the face yellow: whole length 300 inches, wing 120, tail 60. _Female_ similar. _Young_ brown; chin and cheeks whitish; neck greyish, with the tips of the feathers black; breast white, with blackish-brown mottlings; belly black.

_Hab._ Sea-coasts and inland waters of Central and South America.

This appears to be the only Cormorant met with on the coasts and inland waters of South America north of Buenos Ayres; but two other species are found in Southern Chili and Patagonia, which may probably likewise occur in the southern provinces of the Republic[3].

[3] Namely, _P. imperialis_, King, and _P. albiventris_ (Lesson). See Zool. Chall., Birds, p. 121. It was probably one of these two species that Durnford found nesting on Tombo Point, south of Chupat (_cf._ Ibis, 1878, p. 399).

Azara tells us that this Cormorant is not uncommon in Paraguay, and Mr.

Barrows found it an "abundant resident" at Concepcion in Entrerios.

In the vicinity of Buenos Ayres several well-known authorities have met with it, and Durnford found it common and resident in Chupat.

The name of Brazilian Cormorant, which naturalists have bestowed on this species, is certainly inappropriate and misleading, since the bird is very abundant in La Plata, where the native name for it is _Vigua_; and it is also very common in the Patagonian rivers. It is always seen swimming, sinking its heavy body lower and lower down in the water when approached, until only the slanting snake-like head and neck are visible; or else sitting on the bank, or on a dead projecting branch, erect, and with raised beak, and never moving from its statuesque att.i.tude until forced to fly. It always rises reluctantly and with great labour, and has a straight rapid flight, the wings beating incessantly.

By day it is a silent bird, but when many individuals congregate to roost on the branches of a dead tree overhanging the water they keep up a concert of deep, harsh, powerful notes all night long, which would cause any person not acquainted with their language to imagine that numerous pigs or peccaries were moving about with incessant gruntings in his neighbourhood.

Order IX. HERODIONES.

Fam. x.x.xV. ARDEIDae, or HERONS.

About thirty different species of the fish-eating family Ardeidae occur within the limits of the Neotropical Region. Of these, eight or nine are found in greater or less abundance in the provinces of the Argentine Republic. Five of these species are widely distributed in North and South America; the others are restricted to the southern portions of the New World.

315. ARDEA COCOI, Linn.

(COCOI HERON.)

+Ardea cocoi+, _Burm. La-Plata Reise_, ii. p. 508 (Parana, Tuc.u.man, Cordova); _Scl. et Salv. Nomencl._ p. 125; _Hudson, P. Z. S._ 1875, p. 625 (Buenos Ayres); _Durnford, Ibis_, 1877, p. 189 (Buenos Ayres), et 1878, p. 399 (Patagonia); _Gibson, Ibis_, 1880, p. 158 (Buenos Ayres); _White, P. Z. S._ 1883, p. 41 (Cordova); _Barrows, Auk_, 1884, p. 271 (Entrerios).

_Description._--Above grey; head above, wings, and tail plumbeous black; beneath white, neck and sides of belly striped with black: whole length 360 inches, wing 180, tail 70. _Female_ similar.

_Hab._ North and South America.

In size, form, and colour the Cocoi closely resembles the Common Heron of Europe; in flight, language, and feeding-habits the two species are identical, albeit inhabiting regions so widely separated. In the southern part of South America it is not seen a.s.sociating with its fellows, nor does it breed in heronries; but this may be owing to the circ.u.mstance that in the temperature countries it is very thinly distributed, and it is highly probable, I think, that in the hotter regions, where it is more abundant, its habits may not appear so unsocial. Though they are always seen fishing singly, they pair for life, and male and female are never found far apart, but haunt the same stream or marsh all the year round. Azara says that in Paraguay, where it is very scarce, it goes in pairs and breeds on trees. On the pampas it makes its solitary nest amongst the rushes, and lays three blue eggs.

The following general remarks on the Heron apply chiefly to the _Ardea cocoi_, and to some extent also to other species of the Heron family.

I have observed Herons a great deal, and think that there is much to be said in support of Buffon's opinion that they are wretched, indigent birds, condemned by the imperfection of their organs for a perpetual struggle with misery and want.

Much as the different species vary in size, from the _Ardea cocoi_ to the diminutive Variegated Heron of Azara (_Ardetta involucris_), no bigger than a Snipe, there is yet much sameness in their conformation, language, flight, nesting and other habits. They possess a snake-like head and neck, and a sharp taper beak, with which they transfix their prey as with a dart--also the serrate claw, about which so much has been said, and which has been regarded as an instance of pure adaptation. A curious circ.u.mstance has come under my observation regarding Herons.

Birds in poor condition are very much infested with vermin; whether the vermin are the cause or effect of the poor condition, I do not know; but such is the fact. Now in this region (the Argentine Republic) Herons are generally very poor, a good-conditioned bird being a very rare exception; a majority of individuals are much emaciated and infested with intestinal worms; yet I have never found a bird infested with lice, though the Heron would seem a fit subject for them, and in the course of my rambles I have picked up many individuals apparently perishing from inanition. I do not wish to insinuate a belief that this immunity from vermin is due to the pectinated claw; for though the bird does scratch and clean itself with the claw, it could never rid the entire plumage from vermin by this organ, which is as ill adapted for such a purpose as for "giving a firmer hold on its slippery prey."

The Spoonbill has also the serration, and is, unlike the Heron, an active vigorous bird and usually fat; yet it is much troubled with parasites, and I have found birds too weak to fly and literally swarming with them.

I merely wish to call the attention of ornithologists to the fact that in the region where I have observed Herons they are exempt in a remarkable degree from external parasites.

Much has also been said about certain patches of dense, clammy, yellowish down under the loose plumage of Herons. These curious appendages may be just as useless to the bird as the tuft of hair on its breast is to the Turkey-c.o.c.k; but there are more probabilities the other way, and it may yet be discovered that they are very necessary to its well-being. Perhaps these clammy feathers contain a secretion fatal to the vermin by which birds of sedentary habits are so much afflicted, and from which Herons appear to be so strangely free. They may even be the seat of that mysterious phosph.o.r.escent light which some one has affirmed emanates from the Heron's breast when it fishes in the dark, and which serves to attract the fish, or to render them visible to the bird.

Naturalists have, I believe, dismissed the subject of this light as a mere fable without any foundation of fact; but real facts regarding habits of animals have not unfrequently been so treated. Mr. Bartlett's interesting observations on the Flamingoes in the Society's Gardens show that the ancient story of the Pelican feeding its young on its own blood is perhaps only a slightly embellished account of a common habit of the bird.

I have not observed Herons fishing by night very closely, but there is one fact which inclines me to believe it probable that some species might possess the light-emitting power in question. I am convinced that the _Ardea cocoi_ sees as well by day as other diurnal species; the streams on the level pampas are so muddy that a fish two inches below the surface is invisible to the human eye, yet in these thick waters the Herons fish by night and by day. If the eye is adapted to see well with the bright sun shining, how can it see at night and in such unfavourable circ.u.mstances without some such extraneous aid to vision as the attributed luminosity?