San Diego County, California, US
Cleaning out a tree hole. Probable nest cavity.
The Oak Titmouse (Baeolophus inornatus) is a passerine bird in the tit family Paridae. The American Ornithologists' Union split the Plain Titmouse into the Oak Titmouse and the Juniper Titmouse in 1996, due to distinct differences in song, preferred habitat, and genetic makeup.