Bushtit, Jackson Bottom Wetlands, Hillsboro, Oregon on 26 March 2009 by Greg Gillson.
Outside of the breeding season, these tiny, long-tailed balls of gray fluff stay in family flocks and small groups of rarely more than 35 individuals. In the backyard, they search for spiders and small bugs among the leaves of ferns, bushes, trees, and even in crevices in the window sills or siding of the house. Here the constantly twittering birds seem to crawl in short jerky flight from one bush to another, a couple of birds at a time; rarely does the whole flock take flight at once.
In spring they search for bugs among willow catkins, getting covered with yellow pollen, as shown on the bird above. Some birds with excessively pollen-covered heads have been mistaken for Verdin, a similar yellow-headed bird found in the cactus deserts of the Southwestern United States.
Bushtits are residents from extrmeme SW British Columbia, southward from California to Texas. They also occur south in the mountains through Mexico to Guatemala.
In the Pacific NW they are scarce and local east of the Cascades in south-central Washington, more widespread, but still local east of the Cascades of Oregon along rivers and in juniper rimrock canyons and in towns. They are found in southern and southwestern Idaho, and southward. These birds have extended their range and become more common in many areas east of the Cascades through the Great Basin deserts in recent years.
West of the Cascades they are common residents in lower elevations throughout western Washington and Oregon, south through northern California, and from there south.
There are several races, each differing only slightly from one another. The bird in the photo above is typical of those west of the Cascades, quite brownish, especially the crown. Birds east of the Cascades and southward through the Great Basin are a much flatter pale gray, including the crown.
You can attract Bushtits to your yard with a suet feeder. On the small block of suet, a dozen or more birds may cover every inch as they feed!