David Anderson 9 months ago 3 min read. The bib is bright red-orange, the chest is white with red on the sides of the belly and on the caudal covers. In early spring, a narrow strip of scrub and chaparral along the Pacific Coast starts buzzing with the sights and sounds of the coppery and green Allen's Hummingbird. Allen’s hummingbirds are medium-sized birds with a slightly curved black bill. It is a small bird, with mature adults reaching only 3 to 3.5 in (76 to 89 mm) in length. OUR DATA: We use the most recent data from these primary sources: AnAge, UMICH, Max Planck, PanTHERIA, Arkive, UKC, AKC. Allen’s Hummingbird Facts. A close relative of the Rufous Hummingbird, Allen's has a more limited range, nesting mostly in California. The male's throat is an iridescent orange-red. Males have plumage similar to that of the rufous species coupled with an iridescent green hue on the cap and back. Males flash their brilliant reddish orange throat and put on an elaborate show for the females, swinging in pendulous arcs before climbing high into the sky and diving back down with a sharp squeal made by their tails. The male has a green back and forehead, with rust-colored (rufous) flanks, rump, and tail. Allen's hummingbird (Selasphorus sasin) is a species of hummingbird. Males flash their brilliant reddish orange throat and put on an elaborate show for the females, swinging in pendulous arcs before climbing high into the sky and diving back down with a sharp squeal made by their tails. This is one of the two common nesting hummingbirds in northern California gardens (Anna's is the other). A close relative of the Rufous Hummingbird, Allen's has a more limited range, nesting mostly in California. Characteristics and Identification Has a rufous tail, green back, and dark bill; difficult to safely separate from immature Rufous. Discover How Long Allen's Hummingbird Lives. In early spring, a narrow strip of scrub and chaparral along the Pacific Coast starts buzzing with the sights and sounds of the coppery and green Allen's Hummingbird.