By: Bill Reiner
If you feed birds in the winter, you probably know the goldfinches well already. Tiny seed-eaters that throng to the feeders, often fluttering on zebra-striped wings, they utter twittering calls that are cheerful one moment, plaintive the next, until an opening appears among the larger birds. They will partake of many different seeds, but are partial to thistle, and will mob a thistle feeder with fanatic intensity.
“Goldfinch” seems an unlikely name for most of them, though, their bodies plainly feathered in drab olives, browns, and grays. Most show merely a yellowish tint on the body feathers or a splash of yellow on the wings. In the winter, only the male Lesser Goldfinches (pictured above) display the extensive and vibrant saffron yellow that earned these birds their name.
Of the four North American bird species that ornithologists have grouped into the goldfinch genus (Spinus), three may come to your feeder in central Texas: Lesser Goldfinches, American Goldfinches, and Pine Siskins. The fourth, Lawrence’s Goldfinch, is a specialty of California and neighboring states, though a few have wandered to west Texas.
The streaky brown plumage of a Pine Siskin may make it seem closer kin to the sparrows or to the House Finch, but its small size, more deeply notched tail, and more pointed bill, mark it as a goldfinch. It will also show the characteristic goldfinch yellow when it flies – in this case, a long, pale yellow streak down each wing, which flashes as the bird flits away.
Pine Siskins are irruptive winter visitors to central Texas – meaning they are irregular, occurring here some years but not others, mostly in response to food supply farther north. When food is abundant in Canada or the northern United States, especially the pine seeds that they expertly extract with their slender bills, we may see no siskins that winter.
American Goldfinches are regular winter residents, but depart in spring for breeding grounds farther north. These are the only North American finches whose appearance changes markedly with the season. While here, the males and females look much alike, in unstreaked gray-brown plumage, often washed yellowish on the belly (but whitish under the tail), and set off by striking black-and-white wings. But on their breeding grounds, the males’ body plumage transforms to startling yellow with a jet-black cap. You can see a hint of that color in a shoulder patch on a wintering bird, or sometimes a few black crown feathers. A late migrant may show some smattering of yellow feathers before the bird wings northward.
Food, for these birds, means seeds, but unlike most sparrows and other seed-eating species, goldfinches and siskins feed primarily above the ground. They inch out onto the slenderest of twigs and wildflower stalks, and dangle in acrobatic poses, to pluck seeds that would be out of reach of many other birds. For this, their small size is a definite advantage. More about that, and about our only year-round resident goldfinch, in the next Texas Naturalist’s Notes.