On the Mexican side of the Rio Grande this species is found farther south than on the western bank, owing to the rugged character of the country. In Texas its extreme southern point is a little above Reinosa, on the first highlands on the bank.
Don Pablo de la Llave, a Mexican naturalist, states, in an account of this species (Registro Trimestre, I, p. 144, Mexico, 1832), that he attempted its domestication in vain. In confinement it was very timid, all its movements were rapid, and, although he fed his specimens for a long time each day, they seemed to become more wild and intractable. It was found by him in all the mesquite regions of Northern Mexico.
Specimens of this Partridge were taken near San Pedro, Texas, by Mr. J. H. Clark, and in New Leon, Mexico, by Lieutenant Couch. According to Mr. Clark, they are not found on the grassy prairies near the coast. He met with them on Devil’s River, in Texas, where his attention was at first directed to them by their very peculiar note, which, when first heard, suggested to him the cry of some species of squirrel. In the valley of the Lower Rio Grande he also met with these birds in companies of a dozen or more. Their food, on the prairies, appeared to be entirely insectivorous; while on the Lower Rio Grande all the specimens that were procured had their bills stained with the berries of the opuntia. They were not shy, and would rather get out of the way by running than by flying. At no time, and under no circumstances, were they known to alight in bushes or in trees. They were only known to make mere scratches in the ground for nests, and their situations were very carelessly selected. Young birds were found in June and in July.
Lieutenant Couch first met with this species about sixty leagues west of Matamoras, and not until free from the prairies and bottom-land. It was occasionally noticed, apparently associating with the Ortyx texana, to which it is very similar in habit.
Dr. Kennerly found them everywhere where there was a permanent supply of fresh water, from Limpia Creek, in Texas, to San Bernardino, in Sonora. They were met with on the mountain-sides, or on the hills among the low mesquite-bushes and barrea. They apparently rely more upon their legs than upon their wings, ascending the most precipitous cliffs or disappearing among the bushes with great rapidity.
The most western point at which Dr. Heermann observed this species was the San Pedro River, a branch of the Gila, east of Tucson. There a flock of these birds ran before him at a quick pace, with outstretched necks, heads elevated, crests erect and expanded, and soon disappeared among the thick bushes that surrounded them on all sides. After that they were seen occasionally until they arrived at Lympia Springs. Lieutenant Barton informed Dr. Heermann that he had procured this species near Fort Clark, one hundred and twenty miles west of San Antonio, where, however, it was quite rare. It was found abundantly on the open plains, often starting up before the party when passing over the most arid portions of the route. They also seemed partial to the prairie-dog villages. These, covering large tracts of ground destitute of vegetation, probably offered the attraction of some favorite insect.
Dr. Woodhouse met with this species on only one occasion, as the party was passing up the Rio Grande, at the upper end of Valleverde, on the west side of the river, on the edge of the sand-hills, feeding among the low bushes. They were exceedingly shy and quick-footed. He tried in vain to make them fly, and they evidently preferred their feet to their wings as a means of escape. He was told that they were found above Santa Fé.
Mr. Dresser found this species on the Rio Grande above Roma, and between the Rio Grande and the Nueces they were quite abundant; wherever found, they seemed to have the country to themselves to the exclusion of other species. He reports them as very difficult to shoot, for the reason that, whenever a bevy is disturbed, the birds scatter, and, running with outstretched necks and erected crests, dodge through the bushes like rabbits, so as soon to be out of reach. He has thus seen a flock of ten or fifteen disappear so entirely as to render it impossible to obtain a single one. If left undisturbed, they commence their call-note, which is not unlike the chirp of a chicken, and soon reunite. It was utterly out of the question to get them to rise, and the only way to procure specimens was to shoot them on the ground. Near the small villages in Mexico he found them very tame; and at Presidio, on the Rio Grande, he noticed them in a corral, feeding with some poultry. He did not meet with their eggs, but they were described to him, by the Mexicans, as dull white, with minute reddish spots.
The egg of the Callipepla squamata is regularly oval, being much more elongated than with any other species of this family. It measures 1.35 inches in length by .95 in breadth. Its ground-color is a creamy white, and its surface is minutely freckled with specks of a pale drab.