CARDON WOODPECKER
HABITS
In describing and naming this race, Dr. Joseph Grinnell (1927a) says:
In its main characters similar to Centurus uropygialis uropygialis, but general coloration much darker: whole head (except for red patch on crown) and anterior lower surface strongly tinged with snuff brown rather than pale drab; and white barring on closed wings, tail, dorsum, rump, flanks, and lower tail coverts, narrower, leaving the black-barring correspondingly broader. Similar to C. u. brewsteri, but size larger, and coloration darker, in the same respects though not to quite so great a degree as shown in comparison with uropygialis. In other words, the new form differs from both the previously known races in the deeper brown tinge of the head and lower surface and in the greater degree of predominance of black over white in the barring.
He says of its range: “So far as now known, only the giant cactus (cardon) association in the northern section of the Lower Californian peninsula, from about latitude 30° to latitude 31°. Life-zone, Lower Sonoran.” The 1931 Check-list extends the range northward “along the western rim of the Colorado Desert to about latitude 32°.”
A. W. Anthony (1895a) says of the haunts of this woodpecker in Baja California: “The range of this species along the Pacific slope is exactly coextensive with that of Cereus pringlei, becoming common with that cactus a short distance below Rosario and seldom if ever being seen at any distance from the shelter of its mighty branches. At the mission, where the cardons were very large and abundant, to within a short distance of the mesquite thickets, this Woodpecker delighted in making frequent forays into the lesser growth, spending hours in hammering on the mesquite trunks and hunting through their branches, always beating a precipitate retreat to the cactus on the hillsides above at the first sign of danger.”
I can find nothing further of consequence published on the habits of the cardon woodpecker, which doubtless do not differ materially from those of its Arizona relative.
The eggs are similar to those of the Gila woodpecker. The measurements of 11 eggs average 23.59 by 18.30 millimeters; the eggs showing the four extremes measure 25.6 by 18.1, 24.5 by 19.8, 21.9 by 17.8, and 22.1 by 17.3 millimeters. Griffing Bancroft has a still larger egg, which measures 26.4 by 21.8 millimeters.