#nest

Globe mallow chimney bee, Diadasia diminuta, Apidae

Found throughout western North America, this species is solitary and each female builds its own nest, though often ideal nest sites have dozens or hundreds of individual nests. The purpose of the chimney entrance is still debated.

I'm very lucky to have ravens nesting in the back yard this year. The male spends much of the day in a nearby cottonwood snag keeping watch, while the female keeps mostly hidden – except for a few tail feathers poking out of the nest. I expect to see more of her once there are chicks to feed.

I am reasonably sure these are Chihuahuan ravens (Corvus cryptoleucus), but the field marks are scant. The bird's head shape is somewhat blocky, and its hackles (chin feathers) are not very pronounced. To me its call also seems more nasal and crow-like than the deeper call of a common raven (C. corax), like a common raven with a cold. But both species occur here, and they are easy to confuse.