| backyard birding | GOING FOR THE GOLD

Color definitely matters in the world of the American goldfinch, where females select their potential mates based on the brightness of their plumage By Doreen Cubie

the air,” says Tarvin. “Usually one bird begins and it is joined by a couple of other males.” The exact purpose of this sky dance is unknown, but the sci- entist suspects it is part of courtship. Male goldfinches have their

In an article not long ago, NationalWildlife asked readers to name which North American bird they would most like to see. In the letters and emails that followed, the number one response, by far, was the Ameri- can goldfinch. It’s easy to understand why. According to data compiled by the Cornell Lab of Ornithology’s Feeder- Watch Project, the goldfinch is one of the most common back- yard species in almost every region of the country. It also is one of the most colorful. Dur- ing the warmer months, the lemon-yellow creature can instantly brighten up a bird feeder. Even in winter, when its plumage dulls to muted shades of brown and ocher, the song- bird is a welcome sight. The most widespread of the

three North American goldfinch species, Spinus tristis also has caught the eye of scien-

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tists, who have studied every- thing from how the species can survive frigid winters to how it reacts to pesticides and habitat disturbance. Like backyard birders, some researchers have focused primarily on the bird’s striking plumage, and they have discovered there is much more to it than meets the eye. For the past nine years, Keith

Tarvin and his colleagues at Oberlin College in Ohio and Trinity University in Texas have been examining the com- plex interplay between color, status and sex in the lives of American goldfinches. A pro- fessor of biology at Oberlin, Tarvin spends his summers in fields and forest edges where these birds nest.When he begins his research in late June, male goldfinches are showing off their colors in a fluttering display called a butterfly flight. “The males make circles high in

A FEMALE and male American goldfinch share a seed feeder during summer. The species usually does not begin breeding in earnest until mid-July.

work cut out for themwhen it comes to wooing a female. Banding studies show almost equal numbers of the sexes fledge fromnests, butmales tend to live longer. As a result, the breeding population of goldfinches hasmanymore males, and females can afford to be choosy when selecting a mate.Not only do they go for color, but the brighter the better. “Color matters,” says Tarvin,

who explains the vivid hues of a goldfinch’s breeding plumage come from carotenoid pig- ments, the same group of chemicals that make carrots orange. The birds acquire this substance from their diet, so when females pick the brightest males to mate with, they are getting not only the best for- agers but ultimately the best

Create a Backyard

BirdHaven NWF’s Certified Wildlife Habitat™ program provides homeowners with the information they need to create inviting outdoor spaces for a wide range of bird species using native plants and other resources. For more, visit www.nwf.org/nwfgarden.

SCOTT LESLIE (MINDEN PICTURES)