This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the white-throated sparrow.
On occasion during migration seasons, we are treated to a visit by a bird rarely seen here. Recent sightings of a white-throated sparrow are an example. These sparrows are familiar winter birds in the eastern and southern parts of the United States and along the coast of California, but the few that we see here in fall are headed further south.
The white-throated is a large, plump sparrow with a long tail and legs. A white throat patch on a gray breast and yellow patches between the eyes and bill are identifying traits. Two adult morphs, the white-striped and tan-striped, differ in the color of the stripes above the eyes and on the crown.
Most white-throated sparrows breed in the boreal forests across Canada. Their breeding biology is unique among birds since, most of the time, a pair consists of two opposite-colored morphs. White-colored morphs are more aggressive and both males and females sing. Tan-colored females are more attentive parents.
These sparrows mainly eat the seeds of weeds and grasses, adding insects to their diet in summer and berries when available. They most often forage on the ground, close to the cover of dense thickets. Their distinctive song can be heard even in winter.
Migrating at night, these sparrows are among the bird species most commonly killed by colliding with buildings in their path. According to the American Bird Conservancy, “up to 1 billion birds may be killed annually in building collisions.” Its website, abcbirds.org, is a good resource for making buildings, including our homes, more bird friendly.
For information on future events, visit www.weminucheaudubon.org and www.facebook.com/weminucheaudubon/.