Rufous Hummingbird, Forest Grove, Oregon on 21 April 2010 by Greg Gillson.
The Rufous Hummingbird is common throughout the Pacific NW. Males first arrive along the southern Oregon coast in early February and reach Portland and the northern Oregon coast about the first of March. From then on through April reports increase northward, east of the Cascades, and into the mountains. Males arrive about two weeks earlier than females and set up a feeding territory that they defend vigorously against all other hummingbirds.
When the females arrive, they mate and then set up a separate nesting territory. Females take care of all nesting, incubation, and feeding duties.
Interestingly, Rufous Hummingbirds breed as far south as SW Oregon, but apparently not (or rarely) into northern California. Brookings, on the southern Oregon coast, seems to be the dividing line between breeding Rufous Hummingbirds to the north and Allen's Hummingbirds to the south.
Male Rufous Hummingbirds are cinnamon-colored with bright reddish-orange throats (see photo above). Some males also have green backs--thus appearing as Allen's Hummingbirds. Female Rufous Hummingbirds have green backs and lack the colorful throat, and are nearly identical to female Allen's Hummingbirds. In both cases, narrower tail feathers in the Allen's can separate them in-hand or with close-up photos at just the right angle.
Rufous Hummingbirds are most common in moist Coast Range forests and the west slope of the Cascades. They are found in other moist forests , riparian areas, and in towns throughout the Pacific NW. They feed on flower nectar and insects.
After mating, males generally depart into the mountains and start heading south to Mexico for the "winter." It is unusual to see adult male Rufous Hummingbirds in the breeding areas much beyond the first half of July. Females start migrating south in August and it is mostly immatures that are present in the Pacific NW from mid summer to the first week of October.
For instructions on making hummingbird nectar to attract them to your yard, and debunk some myths, see: Bird feeding... Hummingbirds that appeared here back in April 2009.
West of the Cascades, and in some towns just east of the Cascade crest, from Vancouver, British Columbia, southward, the Anna's Hummingbirds are found year-round.