The dark-eyed junco (male shown here) is a species of sparrow that is one of Georgia’s most common yard birds in fall and winter. Scientists have accumulated a large store of data on bird behavior and ecology from studies of juncos. KEN THOMAS / WIKIPEDIA COMMONS

Little bird makes big contribution to what scientists know

The dark-eyed junco, one of Georgia’s most common yard birds in fall and winter, usually gets only scant attention as it scratches for seeds in the leaf litter or grabs seeds spilled on the ground from bird feeders.

But bird experts say the junco, a sparrow species, deserves more respect. For one thing, the little gray bird has contributed to an unsurpassed wealth of scientific knowledge about bird behavior and ecology. A 2014 documentary movie by Indiana University biologists about the bird’s value to science is titled “The Ordinary Extraordinary Junco.” (

Among the many scientific findings originally gleaned from juncos is that seasonal changes in length of daylight prompt birds to mate or migrate.

Few North American birds are as abundant and widespread as juncos, which occur in every state and as far south as Mexico. They breed mostly in Canada and Alaska during summer. A small population also nests in North Georgia’s mountains at elevations above 3,200 feet.

Most juncos migrate in winter, although their seasonal movements can be complex. Some may migrate only short distances, such as from higher to lower elevations; others may travel hundreds of miles south to reach winter grounds. Over much of the eastern United States, the junco is often known as the ‘snowbird’ because it appears around the time of the first snow and departs in early spring.

Female juncos usually migrate farther south than males in winter, and so you might see more females than males in Georgia at this time of year.

Male juncos are dark gray overall except for white underparts; females are brown rather than gray. When alarmed, both sexes flash their white outer tail feathers as they seek cover.

IN THE SKY: From David Dundee, Tellus Science Museum astronomer: The annual Geminid meteor shower will be visible this weekend and through next week, reaching a peak on Thursday and Friday nights of 50 meteors per hour. For best viewing, look in the eastern sky from about midnight until dawn.

The moon will be first-quarter next Saturday. Mercury and Venus (shining brilliantly this month) appear low in the east just before sunrise. Mars is low in the southwest at dusk and will appear near the moon for several evenings.

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