Those yellow birds like shards of sunlight in your yard are American goldfinches. Among the smallest members of the finch family, goldfinches are gifts to gardeners. Even if deer ate all your daylilies, these birds will brighten your day.

The U.S. has three goldfinch species, two of which are found only in the western states. American goldfinches (Spinus tristis) are found all across America, and in our area, they are with us all year long.

The birds molt into their breeding plumage in mid-spring. Females don new olive-green feathers, good camouflage for nesting. The canary-yellow plumage on a goldfinch male makes him a garden dandy. Both sexes have black flight feathers and pale wing-bars, but the male tops off his yellow outfit with a sexy black beret.

Goldfinch flocks move around in non-breeding seasons, but they don’t migrate far. The reason they seem to disappear in autumn is that they molt into drab attire. In September, when breeding season is largely over, the yellow males start to look patchy. By mid-November, males and females both have brownish-gray plumage, with the males retaining a bit of yellow on their shoulders.   

Goldfinch songs and calls are distinctive. The male’s courtship song is high-pitched and musical, a twittery, tinkling series of notes, like a tiny far-off wind chime. In their undulating flight, both males and females issue flight calls at the low curve of the sine wave, as if urging themselves to achieve that upper curve. That diagnostic call sounds like “perchickoree” or “potato chip.” In addition, they often do plaintive contact calls—the sounds that gave them the name tristis.

Like all birds, goldfinches need food, water, and shelter to survive. Not deep-forest birds, they prefer open woodlands, weedy areas and meadows, and streamsides, with shrubs for cover and nest sites. These little birds are vegetarians: their diet consists almost entirely of seeds. Unlike most seed-eating birds, they seldom feed insects to their nestlings, but stuff those noisy gaping beaks with regurgitated seeds. They especially like thistle seeds, and also use soft thistle and cattail down to line their nests. Thistles flower later in summer, so goldfinches nest later than many other garden birds.

The female makes the nest, usually 4 to 14 feet up in an upright fork of a shrub or tree. She weaves the nest from plant fibers, glues it with webbing from spiders or caterpillars, and lines it with plant down. She does all the incubation; the male brings her food. He also feeds the youngsters until they fledge, while she may go on to make a second nest.

Though I seldom see goldfinches drinking or bathing at my birdbath, an unexpected consequence of hanging hummingbird feeders is the pleasure of watching goldfinches leaning in to drink water from the ant-wells. Another surprising appropriation: catnip grown for our cats provides food for the birds. Stems of catnip start bobbing and there’s a goldfinch or two, climbing around on the plants or head-down deep in succulent catnip seeds. (Catnip is a mint that spreads easily, so I wouldn’t plant it unless you want to delight your cats.)

A cheerful sight at birdfeeders, goldfinches readily eat hulled sunflower seeds, but prefer the tiny black nyjer seeds, an exceptional energy source. (Nyjer is often called “thistle” but it’s actually the seeds from an African daisy.) Pines and spruces in your yard provide great year-round shelter and their winter cones can be mined for seeds.

To lure American goldfinches to your garden, plant native thistles (Cirsium), coneflowers (Echinacea), black-eyed Susans (Rudbeckia) and sunflowers (Helianthus). When blooming is finished, don’t be quick to deadhead the plants. Goldfinches eager to take the seeds will come to your garden like flying flowers.

Happily, these beautiful birds are common and widespread; their conservation status is “species of least concern” and their population is stable. That’s good news.