Acorn Woodpecker (Melanerpes formicivorus) [XC494259]
by Thomas G. Graves from Pamo Valley, Ramona, San Diego County, California, United States (call, song)
(Melanerpes formicivorus) [XC565034]
by Paul Marvin from Rucker Canyon, Chiricahua Mountains, United States (alarm call)
Nest
In a hole cut into the trunk of a tree.
Subspecies
Proposed subspecies martirensis (northern Baja California) considered indistinguishable from bairdi. Subspecies lineatus doubtfully distinct from albeolus.
The following 7 subspecies are recognised:
bairdi Ridgway, 1881 - North-western Oregon south to northern Baja California.
formicivorus (Swainson, 1827) - Arizona, New Mexico and western Texas south to south-eastern Mexico (west of Chiapas).