AUTUMN 2000/VOLUME 14, NUMBER 4

Become A Member
Project FeederWatch

Come autumn, do you sometimes wonder what happens to all those blustering, boldly patterned male House Sparrows of spring and summer? Take a careful look at the plain female House Sparrows on the sidewalks or at your feeder and you'll discover that the males are there too"disguised" as females.

We may not all like the introduced House Sparrow, because it often competes with our native species for nesting cavities. But House Sparrows are a convenient place to begin a discussion on molt, because they are, in most regions, an abundant, easily observed year-round resident.

Because feathers wear and fade, all birds must molt. This is typically done in discrete seasonal cycles. Molt strategies can be simple or complex, depending on the species. The
majority of birds have one major molt in which their entire plumage is replaced, and one or more partial seasonal molts during the course of the year. Most birds living permanently or as summer visitors in the northern temperate zones conduct their major molts in late summer and early autumn. With the new plumage often comes a dramatic change in appearance, either as a complete change in color and pattern or merely through a veiling effect. The female-like appearance of the male's underlying pattern and colors is temporarily veiled because the feather is broadly tipped with another, more somber color. These tips gradually wear away, revealing the underlying "field guide" plumage just in time for spring.

Head of female

Note general female-like appearance; pale bill, concealed black breast patch, pale supercillium.                 Male in spring with pale feather tips worn away   Display pose with chest thrust forward to show off black patch.     Research has shown that males with larger chest patch are more successful at attracting females.

Take time to cultivate an eye for the seasonal changes in birds. Come late summer and autumn, watch for the change to more reclusive, quiet behaviors and for changes in form and color. Look for feathers lying along marsh shores or bathing pools, alongside footpaths or within secluded thickets. You'll find it heightens your sense of the changing seasons.