A History of North American Birds, Land Birds. Volume 1. Robert Ridgway

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      The careful observations of Mr. Robert Ridgway have led him to the conviction that the name bestowed upon this species of “Mountain Mocking-Bird” is doubly a misnomer. It is not at all imitative in its notes, and it is almost exclusively a resident of the artemisia plains. It seems to be chiefly confined to the great central plateau of North America, from Mexico almost to Washington Territory. Specimens have been procured from Cape St. Lucas, the Lower Colorado, Mexico, and Texas, on the south, and Nuttall met with it nearly as far north as Walla-Walla. It probably occupies the whole extent of the Great Basin.

      Dr. Kennerly, who met with it while crossing the arid mesas west of the Rio Grande, says that while singing it was usually perched upon some bush or low tree. It was frequently seen seeking its food upon the ground, and when approached, instead of flying away, it ran very rapidly, and disappeared among the low bushes.

      During the winter months it was observed near San Antonio, Texas, by Mr. Dresser; and was also found by him to be common about Eagle Pass. He noticed the same peculiarity of their running instead of their flying away when disturbed. They preferred the flat, bush-covered plains. A few remained to breed, as he obtained the eggs there, although he did not himself meet with one of the birds in summer.

      It is generally represented as keeping chiefly on the ground, and obtaining its food in this position. General Couch speaks of it as Sparrow-like in its habits.

      Mr. Nuttall describes its song as cheering, and the notes of which it is composed as decidedly resembling those of the Brown Thrush (Harporhynchus rufus). He claims for it some of the imitative powers of the Mocking-Bird (Mimus polyglottus), but in this he is not supported by the observations of others. He met with its nest in a wormwood (Artemisia) bush on the border of a ravine; it contained four eggs of emerald green, spotted with dark olive, the spots being large, roundish, and more numerous at the larger end. The nest was composed of small twigs and rough stalks, and lined with strips of bark and bison-wool. The female flew off to a short distance, and looked at her unwelcome visitors without uttering any complaint.

      The nests of this bird, so far as I have seen them, are all flat, shallow structures, with very slight depression, and loosely and rudely constructed of an intermingling of strips of bark with rootlets and the finer stems of herbaceous plants. Their eggs, usually four in number, do not vary essentially in size, shape, or marking. They measure 1 inch in length, and from .73 to .75 in breadth. Their ground color is a bright greenish-blue, marked with deep olive-brown spots, intermingled with blotches of a light lilac. There are slight variations in the proportion of green in the shade of the ground color, and also in the number and size of the spots, but these variations are unimportant.

      The following are Mr. Ridgway’s observations upon the habits of this species. They are full, valuable, and very carefully made:—

      The Oreoscoptes montanus is a bird peculiar to the artemisia wastes of the Great Basin, being a characteristic species of the region between the Sierra Nevada and the Rocky Mountains. It is exclusively an inhabitant of the “sage brush,” and is partial to the lower portions of the country, though it is not unfrequent on the open slope of the mountains. A more unappropriate term than “Mountain Mocking-Bird” could hardly have been chosen for this species, as its predilection for the valleys, and the fact that its song is entirely its own, will show. In my opinion, the term “Sage Thrasher” would be more appropriate.

      In the neighborhood of Carson City, Nevada, these birds arrived about the 24th of March, and immediately upon their arrival began singing. At this time, with the Sturnella neglecta and Poospiza belli, they made sweet music in the afternoon and early morning, in the open wastes of “sage brush,” around the city. The birds when singing were generally seen sitting upon the summit of a “sage” bush, faintly warbling, in the course of the song turning the head from side to side in a watchful manner. Upon being approached, they would dart downward, seemingly diving into the bush upon which they had perched, but upon a close search the bird could not be found, until it was heard again singing a hundred yards or more in the direction from which I had approached. This peculiar, circuitous, concealed flight is a very characteristic trait of this bird, and one sure to excite attention.

      As the season advanced, or about the 10th of April, when the pairing season was at hand, the songs of the males became greatly improved, increasing in sweetness and vivacity, and full of rapturous emotion; their manners, also, became changed, for they had lost all their wariness. In paying their attentions to their mates, the males would fly from bush to bush, with a peculiar, tremulous fluttering of the wings, which, when the bird alighted, were raised above the back apparently touching each other; all the while vibrating with the emotion and ecstasy that agitated the singer.

      The song of this bird, though very deficient in power,—in this respect equalling no other species of Miminæ with which I am acquainted,—is nevertheless superior to most of them in sweetness, vivacity, and variety. It has a wonderful resemblance to the beautiful subtle warbling of the Regulus calendula, having in fact very much the same style, with much of the tone, and about the power of the song of the Pyranga rubra.

      When the birds are engaged in incubation, the males become very silent, and one not familiar with their habits earlier in the season would think they never had a voice; in fact, they make no protestations even when the nest is disturbed, for, while blowing the eggs, I have had the parent birds running around me, in the manner of a robin, now and then halting, stretching forward their heads, and eying me in the most anxious manner, but remaining perfectly silent. When the young are hatched the parents become more solicitous, signifying their concern by a low, subdued chuck. At all times when the nest is approached, the bird generally leaves it slyly before one approaches very near it.

      The nest is very bulky, composed externally of rough sticks, principally the thorny twigs of the various “sage bush” plants. Nearer the centre the principal material is fine strips of inner bark of these plants; and the lining consists of finer strips of bark, mingled with fine roots, and bits of rabbit fur. The situation of the nest varies but little, being generally placed near the middle of a bush, that is, about eighteen inches from the ground. It is generally supported against the main trunk, upon a horizontal branch. Several were found upon the ground beneath the bush, one, in fact, embedded in the soil, like that of a Pipilo; or as sometimes the case with the Harporhynchus rufus, others, again, were found in brush-heaps. In all cases, the nest was very artfully concealed, the situation being so well selected.

      This bird is almost equally common in all parts of its habitat, within the limits indicated. In June, we found it abundant on the large islands in the Great Salt Lake, where many nests were found.

      In autumn, it feeds, in company with many other birds, upon berries, “service berries” being its especial favorite.