Verdins (Auriparus flaviceps) are common permanent residents in desertscrub and adjacent riparian woodlands here in southeastern Arizona. They are the only member of the Penduline-tit Family (Remizidae) found here in North America.
These small, active birds are mostly gray with a golden face and small, chestnut shoulder patches (not always visible). Depending on the lighting and the angle of view, their face may appear to be a dull grayish yellow or a bright gleaming gold.
Verdins feed mainly on insects and other small invertebrates, but they also have a fondness for sweets. I have seen them feeding on ripe Saguaro fruit and visiting hummingbird feeders. I spotted this Verdin visiting a dripping sap well on a damaged mesquite (Prosopis sp.) tree at the Sweetwater Wetlands here in Tucson.
A voracious rodent had recently chewed off a large section of the poor mesquite tree's bark, and the injured tree was dripping fresh, sweet sap at the edge of the wound.