Rufous Hummingbird
Allen's Hummingbird
10 cm (4") Common in Rocky Mountains.
Male: told from Ruby-throated hummer by its rufous on body and distinctive wing sound - a shrill metallic whistle.
Female: broad green tail shows rufous. Not safely told from female Rufous' or Allen's. Calliope female is much smaller and its wings extend beyond the tail.
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Distribution Maps
Broad-tailed Hummingbird distribution map