On account of the conspicuous difference in coloration of the young, definite difference in color pattern of back, head, and neck in adults, and comparative rarity of intermediate specimens (which are far less common, relatively, than in the case of Colaptes), I believe that it would be better to consider this form as specifically distinct from S. varius. It is true that specimens do occur that are intermediate between S. nuchalis and S. varius, as well as between the former and if S. ruber; but they may be (and I believe they are) hybrids; certainly there is no more reason for not considering them as such than in the case of Colaptes; and if S. nuchalis is to be considered as merely a subspecies of S. varius then, most certainly, must S. ruber also.
Mr. Ridgway (1877) says of its haunts:
Throughout the country between the Sierra Nevada and the Rocky Mountains, the red-naped woodpecker is a common species in suitable localities. Its favorite summer-haunts are the groves of large aspens near the head of the upper cañons, high up in the mountains, and for this reason we found it more abundant in the Wahsatch and Uintah region than elsewhere; indeed, but a single individual was observed on the Sierra Nevada, and this one was obtained on the eastern slope of the range, near Carson City. It was very rare throughout western Nevada, but became abundant as we approached the higher mountains in the eastern portion of the State. Among the aspen groves in Parley’s Park, as well as in similar places throughout that portion of the country, it was by far the most abundant of the Woodpeckers; and it seemed to be as strictly confined to the aspens as S. thyroideus was to the pines.
The Weydemeyers (1928) say that, in northwestern Montana, “it occurs most abundantly and typically in mixed broad-leaf and conifer associations along streams, where it nests regularly. It ranges less commonly into virgin forests of fir, larch, yellow pine, and hemlock (Tsuga heterophylla) in the valleys; and into arborvitae, lodgepole pine, and spruce woods of the foothills. Occasional birds are seen in alpine fir and spruce woods upward to the lower borders of the Hudsonian zone.”
Courtship.—M. P. Skinner says in his notes: “On May 13, 1915, I saw a red-naped sapsucker drumming on a hollow, dead lodgepole pine; soon he flew to the top of another pine, where his mate was, and the two began bobbing and curtsying in true cake-walk fashion much like flickers, except that these sapsuckers were on a vertical stub. There was no movement of the feet, but the body was bent from side to side, and there was a constant ‘juggling’ motion. The head was tilted back and the bill pointed up at an angle of sixty degrees, with neck outstretched. The neck, head, and bill were in constant motion. That of the bill reminded me of a musical director’s baton.”
Nesting.—The Weydemeyers (1928) say of its nesting habits: “As elsewhere in the state, this bird in Lincoln County nests most commonly in live aspens. Our records for this area include four nests in live aspens, one in a live larch, and one in a dead Engelmann spruce. These nests were all in the Transition zone, near streams, Three of the nests in aspens were in a single tree, in successive years. Nest-hole preparation usually commences immediately upon the arrival of the birds in the spring, about April 20.”
Major Bendire (1895) gives an attractive account of finding a nest of this woodpecker in a live aspen, in a small grove of these trees, near Camp Harney, Oregon, on June 12, 1877: “Their nesting site was directly over my head, about 20 feet from the ground. * * * The entrance to the excavation was exceedingly small, not over 1¼ inches in diameter, about 8 inches deep, and about 4 inches wide at the bottom. It contained three nearly fresh eggs, lying partly embedded in a layer of fine chips.”
He quotes the following observations of Denis Gale:
My observations have been that this subspecies invariably selects for its nesting site a living aspen tree. I have never met with it in any other. This tree favors the mountain gulches and low, sheltered hillsides, at an altitude of from 7,000 to 10,000 feet. Above this point they do not attain sufficient size, and are mostly dwarfed and scrubby. Here in Colorado Sphyrapicus varius nuchalis is seldom found above 9,000 feet or much below 8,000 feet. The aspen tree is short lived, and ere much of a growth is attained, a cross section, in the majority of instances, will show a discolored center of incipient decay, involving half or two-thirds of its entire diameter, with a sound, white sap zone on the outer circumference, next to the bark. This sound, healthy zone nourishes the tree until the decayed core discovers itself in some withered limbs, and frequently the top of the tree manifests the canker.
Such trees the Red-naped Sapsucker selects for its nesting site, and with great perseverance chisels through this tough, sound zone, from 1 to 1½ inches in thickness, commencing with a very small hole and gradually extending its circumference with each stage of the deepening process, working from the lowest center out, till the exact circumference of the intended aperture of entrance is attained. In thus radiating in circles from the central point the minute chips are chiseled out with considerable ease. This mode of working is observed until the tough zone is worked through; what remains then is comparatively easy work; the soft, soggy, lifeless inside is worked into and downward with greater facility, and a roomy, gourd-shaped excavation quickly follows, the female doing the excavating from beginning to end, and, according to exigencies, completes it in from six to ten days. * * *