This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the bushtit.
Within their range in western North America and the highlands of Central America, these birds are common but often inconspicuous. Drab coloration may make it difficult to pick them out from deep within a shrub, but their constant movement and twittering calls are an aid to spotting them.
Bushtits are social birds that typically live in flocks numbering from 10 to 40 birds. The flock moves single file from shrub to shrub while keeping up their soft chatter. To keep warm in cold weather, they huddle close together for the night.
Bushtits are tiny and gray-colored with short, stubby bills and long tails. Birds from different regions show some variation in plumage. The interior group has light brown cheek patches. Differences in eye color — a dark iris in males and light iris in females — makes it possible to distinguish the sexes.
Often thought of as adorable balls of fluff, the “tit” in their name refers to something small. For comparison, a bushtit weighs about half as much as that other small gray bird we are familiar with, the pygmy nuthatch. Light weight confers an advantage to this bird when it forages for small insects and spiders by hanging upside down from narrow twigs and branches. The bushtit can reach the undersides to glean the prey unavailable to heavier birds.
In Spanish, the bushtit is called sastrecillo, or little tailor, a nod to its nest building prowess. Both sexes work together a month or longer to weave a long, hanging nest using spiderwebs, moss, grass, lichen, twigs, leaves and rootlets to make a stretchy sac. The breeding pair often has adult male helper birds when nestlings are being fed, and at night the whole group piles into the nest to roost.
Bushtit ranges have been expanding steadily northward in the last 20 years, thought to likely be a response to climate warming. Bushtits adapt well to new situations and are increasingly found in urban environments. Not originally considered a feeder bird, they have developed a craving for suet and are also seen on finch and even hummingbird feeders.
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