individual female.
Also possibly a hybrid between Nuttall's and Downy- Note that thought the head pattern looks largely like Nuttall's, the white supercillium is thicker almost like Downy's, and that the arrow black band normally crossing the white cheek bar near the beak in Nuttall's is missing.
These discrepancies in typical plumag could (possibly more likely) be attributed to individual variation though.