: Argentine Ornithology, Volume I (of 2) by P. L Sclater, W. H Hudson (books to read in your 20s female .txt) 📖

never been able to see this Sparrow feeding, or

followed by, a young _Molothrus_. Possibly, if it ever hatches the

parasitical egg at all, the voracious young Cow-bird is starved by the

delicate food supplied by its foster-parents.

92. OROSPINA PRATENSIS, Cab. (MEADOW SEED-FINCH.)

 

  +Orospina pratensis+, _Cab. Journ. f. Orn._ 1883, p. 108, tab. i.

      fig. 1.

 

    _Description._--Cap dark greenish yellow; rump yellowish green;

    remainder of upper parts dark brown, feathers of interscapulium and

    of wings and tail edged with yellowish green; inner webs of the

    outer pair of tail-feathers almost wholly white, the next pair with

    a large white spot; under surface yellow, lightest on the throat,

    middle of belly, and crissum; flanks greenish: total length 4·5

    inches, wing 2·5, tail 1·8.

 

_Hab._ Tucuman.

 

Herr Schulz discovered this little Finch, which Dr. Cabanis has referred

to a new genus allied to _Sycalis_, upon the high Sierras of Tucuman,

where it was observed sitting on the stones.

Fam. XI. (ICTERIDÆ, or TROUPIALS.)

 

The Icteridæ or Troupials constitute a large group of Passerine birds

allied to our Starlings (_Sturnidæ_), of which they take the place in

the New World. They are at once structurally distinguishable from

the Starlings by having only 9 primaries in the wing, just as the

Mniotiltidæ of the New World are in a similar manner distinguishable

from the Sylviidæ.

 

In America the Icteridæ play an important part, numbering some 130

species, and extending throughout the two continents from north to

south. Of these, 15 species occur in Argentina, and amongst them are

three species of Cow-bird (_Molothrus_), remarkable for their parasitic

habits, of which Hudson's observations have enabled him to give a full

and, for the first time, a tolerably complete account.

93. AMBLYCERCUS SOLITARIUS (Vieill.). (SOLITARY CASSIQUE.)

 

+Cassicus solitarius+, _Scl. et Salv. Nomencl._ p. 36; _Barrows,

      Bull. Nutt. Orn. Cl._ viii. p. 133 (Entrerios); _Scl. Cat. B._

326.

 

    _Description._--Uniform black; bill white; feet black: total length

    11 inches, wings 4·8, tail 4·5. _Female_ similar, but smaller.

 

_Hab._ Peru, Bolivia, Brazil, Paraguay, and Northern Argentina.

 

Mr. Barrows obtained a single specimen of this species at Concepcion,

and others were seen. It was said to be an excellent song-bird, and to

be more abundant further up the Uruguay River.

94. MOLOTHRUS BONARIENSIS (Gm.). (ARGENTINE COW-BIRD.)

 

+Molothrus bonariensis+, _Scl. et Salv. Nomencl._ p. 37; _Hudson,

Z. S._ 1872, p. 809, 1874, p. 153 (Buenos Ayres); _Durnford,

      Ibis_, 1877, pp. 33, 174 (Chupat); _White, P. Z. S._ 1882, p.

      601 (Buenos Ayres); _Döring, Exp. al Rio Negro, Zool._ p. 41

      (Carhué); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 133

      (Entrerios); _Scl. Cat. B._ xi. p. 335. +Molothrus sericeus+,

      _Burm. La-Plata Reise_, ii. p. 494.

 

    _Description._--Uniform shining purplish black; less lustrous on

    wings and tail; bill and feet black: total length 7·5 inches, wing

    4·5, tail 3·0. _Female_ dark ashy brown, beneath paler; slightly

    smaller in size.

 

_Hab._ Argentina, Paraguay, Bolivia, and Brazil.

 

This species is the _Tordo Comun_ of Azara, and is usually called

"_Tordo_" or "_Pajaro Negro_" by the Spanish, and "_Blackbird_" by

the English-speaking Argentines. A more suitable name, I think, is

the Argentine Cow-bird, which has been given to it by some writers

on ornithology, Cow-bird being the name of the closely allied

North-American species, _Molothrus pecoris_.

 

This Cow-bird is widely distributed in South America, and is common

throughout the Argentine country, including Patagonia, as far south as

Chupat. In Buenos Ayres it is very numerous, especially in cultivated

districts where there are plantations of trees. The male is clothed in a

glossy plumage of deep violaceous purple, the wings and tail being dark

metallic green; but seen at a distance or in the shade the bird looks

black. The female is inferior in size and has a dull, mouse-coloured

plumage, and black beak and legs. The males are much more numerous than

the females. Azara says that nine birds in ten are males; but I am

not sure that the disparity is so great as that. It seems strange and

contrary to Nature's usual rule that the smaller, shyer, inconspicuous

individuals should be in such a minority; but the reason is perhaps that

the _male eggs_ of the Cow-bird are harder-shelled than the _female

eggs_, and escape destruction oftener, when the parent bird exercises

its disorderly and destructive habit of pecking holes in all the eggs it

finds in the nests into which it intrudes.

 

The Cow-birds are sociable to a greater degree than most species, their

companies not breaking up during the laying-season; for, as they are

parasitical, the female merely steals away to drop her egg in any nest

she can find, after which she returns to the flock. They feed on the

ground, where in their movements and in the habit the male has of

craning out its neck when disturbed, they resemble Starlings. The male

has also a curious habit of carrying his tail raised vertically while

feeding. They follow the domestic cattle about the pastures, and

frequently a dozen or more birds may be seen perched along the back of a

cow or horse. When the animal is grazing they group themselves close to

its mouth, like chickens round a hen when she scratches up the ground,

eager to snatch up the small insects exposed where the grass is cropped

close. In spring they also follow the plough to pick up worms and grubs.

 

The song of the male, particularly when making love, is accompanied with

gestures and actions somewhat like those of the domestic Pigeon. He

swells himself out, beating the ground with his wings, and uttering a

series of deep internal notes, followed by others loud and clear; and

occasionally, when uttering them, he suddenly takes wing and flies

directly away from the female to a distance of fifty yards, and performs

a wide circuit about her in the air, singing all the time. The homely

object of his short-lived passion always appears utterly indifferent

to this curious and pretty performance; yet she must be even more

impressionable than most female birds, since she continues scattering

about her parasitical and often wasted eggs during four months in every

year. Her language consists of a long note with a spluttering sound, to

express alarm or curiosity, and she occasionally chatters in a low tone

as if trying to sing. In the evening, when the birds congregate on the

trees to roost they often continue singing in concert until it is quite

dark; and when disturbed at night the males frequently utter their song

while taking flight, reminding one of the _Icterus pyrrhopterus_, which

has only its usual melody to express fear and other painful emotions.

On rainy days, when they are driven to the shelter of trees, they will

often sing together for hours without intermission, the blending of

innumerable voices producing a rushing sound as of a high wind. At the

end of summer they congregate in flocks of tens of thousands, so that

the ground where they are feeding seems carpeted with black, and the

trees when they alight appear to have a black foliage. At such times

one wonders that many small species on which they are parasites do not

become extinct by means of their pernicious habit. In Buenos Ayres,

where they are most numerous, they have a migration, which is only

partial, however. It is noticeable chiefly in the autumn, and varies

greatly in different years. In some seasons it is very marked, when

for many days in February and March the birds are seen travelling

northwards, flock succeeding flock all day long, passing by with a swift

low undulating flight, their wings producing a soft musical sound; and

this humming flight of the migrating Cow-birds is as familiar to every

one acquainted with nature in Buenos Ayres as the whistling of the wind

or the distant lowing of cattle.

 

The procreant instinct of this _Molothrus_ has always seemed so

important to me, for many reasons, that I have paid a great deal of

attention to it; and the facts, or, at all events, the most salient of

them, which I have collected during several years of observation, I

propose to append here, classified under different headings so as to

avoid confusion and to make it easy for other observers to see at a

glance just how much I have learnt.

 

Though I have been familiar with this species from childhood, when I

used to hunt every day for their wasted eggs on the broad, clean walks

of the plantation, and removed them in pity from the nests of little

birds where I found them, I have never ceased to wonder at their strange

instinct, which in its wasteful destructive character, so unlike the

parasitical habit in other species, seems to strike a discordant note in

the midst of the general harmony of nature.

 

 

_Mistakes and Imperfections of the Procreant Instinct of_ Molothrus

bonariensis.

 

The Cow-birds, as we have seen, frequently waste their eggs by

dropping them on the ground.

 

They also occasionally lay in old forsaken nests. This I have often

observed, and to make very sure I took several old nests and placed them

in trees and bushes, and found that eggs were laid in them.

 

They also frequently lay in nests where incubation has actually

begun. When this happens the Cow-bird's egg is lost if incubation is far

advanced; but if the eggs have been sat on three or four days only, then

it has a good chance of being hatched and the young bird reared along

with its foster-brothers.

 

One female often lays several eggs in the same nest, instead of

laying only one, as does, according to Wilson, the _Molothrus pecoris_

of North America. I conclude that this is so from the fact that in

cases where the eggs of a species