Hab. Central regions of the United States, to Mexico, east to mouth of Yellowstone River. Cape St. Lucas. Not recorded from Pacific slope. W. Arizona, Coues. Oaxaca, Sclater.
Salpinctes obsoletus.
Habits. The Rock Wren, so far as its distribution is known, is principally restricted to the high central plains of the Rocky Mountains, from Nebraska to the coast ranges near the Pacific, and from Oregon to Mexico and Lower California. According to Dr. Cooper it is an abundant species throughout the dry, rocky, and barren districts of California, especially in the southern portions, where it comes nearer the coast. They are numerous among the plains on both sides of the Rocky Mountains. Their favorite places are among the rocks, where they are always busily engaged in hunting for insects in the crevices. Dr. Cooper found nests at San Diego in cavities under the tiled roofs of houses, but they all contained young as early as May. At Fort Mojave they began to sing in February, and their song continued throughout the spring. They range to a high elevation among the mountains,
having been found by Dr. Newberry at Klamath Lake in Oregon. Dr. Cooper does not describe their song, but Dr. Heermann speaks of it as only a very weak trill. The latter met with them in the mountainous districts of California, where they were searching for their food among the crevices of the rocks. He afterwards met with them in New Mexico and Texas. They were quite abundant in the Tejon Valley, passing in and out, among and under the boulders profusely scattered over the mountains, searching for spiders, worms, and small insects, in pursuit of which they uttered at intervals a loud and quick note of a peculiarly thrilling character. Lieutenant Couch found them in the sandstone ranges near Patos, in the province of Coahuila. Some of their habits are spoken of as sparrow-like, and, while they have the usual wren-like grating noises, they also possess a song of great variety and sweetness.
Dr. Kennerly met with them among the bushes in the vicinity of the Rio Grande. Their flight he describes as short, the bird generally soon alighting on the ground and running off very rapidly.
This Wren was first discovered by Mr. Say near the Arkansas River, inhabiting a sterile district devoid of trees, hopping along the ground or flitting through the low, stunted junipers on the banks of the river, usually in small flocks of five or six. Nuttall afterwards found them in July on the Western Colorado. The note of the female was charr-charr-te-aigh, with a strong guttural accent, and with a shrill call similar to the note of the Carolina Wren. The old birds were feeding a brood of five young, which, though full grown, were cherished with querulous assiduity. He found them nesting among the rocky ledges, in the crevices of which they hide themselves when disturbed. Mr. Nuttall also met with this species near Fort Vancouver. Mr. Salvin states that in several instances it has been met with in Guatemala.
The eggs of this Wren obtained by Dr. Palmer in Arizona have a clear white ground, sparingly spotted with well-defined, distinct dottings of brownish-red. These are chiefly distributed around the larger end. They vary somewhat in size and shape, some being of a more rounded form, though all have one end more pointed than the other. The length is pretty uniform, .77 of an inch. The breadth varies from .60 to .66 of an inch. They are larger and more oblong than the eggs of any other Wren, except perhaps the mexicanus, and bear little resemblance to any other eggs of this family with which I am acquainted, except those of the Winter Wren, and the egg attributed to T. americanus.
The nest is homogeneous in structure, composed entirely of thin strips of reddish-colored bark and fine roots, interspersed with a few small bits of wool. It is distorted by packing, so that measurements of it would be valueless; its dimensions in its pressed condition are: diameter, 5 inches; depth, 2 inches. The cavity is shallow and saucer-shaped.
From Mr. Ridgway we learn that from the summit of the Sierra Nevada eastward, as far as the party explored, he found this Wren universally distributed. In the middle provinces of the Rocky Mountains it was the most abundant species of the family, but was not so abundant in the Wahsatch Mountains. The general resort of this species was among rocky or stony hill-slopes, though it was not confined to such localities. At Carson City he found it particularly partial to the rubbish of the decaying pine-logs. At Virginia City it was the only Wren seen frequenting the old buildings and abandoned mining-shafts, in its predilection for such places reminding him very much of the Thryothorus ludovicianus, which in its manners it very strongly resembles.