Hummingbird arm bones are relatively smaller, and most of the wing is made up of the equivalent ... there’s a chirping sound—not from their vocal cords but from the fluttering of tail feathers ...

A common species of western mountains, where the male’s diagnostic, cricketlike wing trill is a characteristic sound ... see female and immature calliope hummingbird.

Regardless of the season, Rubys are the common hummingbird in the area. Because their rapid wing beats make a humming sound in flight. Northbound migrants will begin to appear in late March.