Cogswell 1948 Colaptes auratus Nov. 27 - Jewell L., Tilden Park, Contra Costa Co. NE of Berkeley, Calif. one definitely yellow. shafted flicker flew up (from ground?) some where near w end of dam and alighted in matter leafless oak on hillside to N. In attempting to get into position where I could see head markings on it, I flushed it again - and did not see appearance of it afterwards. Presence of yellow was easily compared with several true red. shafted also in same area at same time (one even in same tree) Since I didn't see head markings, however, it could have been an extremely delicate example of C. cafer, tho more likely this sp.