American Tree Sparrow

The American Tree Sparrow is a cheerful and resilient member of the New World sparrow family. Despite its name, this species does not heavily depend on trees; it breeds in the shrubby transition zones of the far northern tundra and spends winters foraging in open, brushy fields, gardens, and backyard bird feeders across the United States and southern Canada. Known for their tolerance of cold winter weather, they often arrive in flocks just as the first snows begin to fall, bringing lively energy to bleak winter landscapes.

Historically classified under the genus Spizella, genetic studies have placed this species into its own monotypic genus, Spizellina. Their sweet, musical songs and active ground-foraging behaviors make them a favorite amongst winter birdwatchers.

Paying close attention to head patterns and bill colors makes identifying the American Tree Sparrow straightforward:

• Plumage: Features a bright, chestnut-rufous cap and a matching rufous stripe behind each eye. The face and neck are light gray.
• Breast: Plain, solid gray-white chest marked by a single, prominent, dark dusky-brown spot right in the center (often referred to as a "stick-pin").
• Bill: Distinctly bicolored, showing a dark/blackish upper mandible and a bright yellow-orange lower mandible.
• Wings and Back: Warm brown back with black streaks, accompanied by two crisp white wingbars on each wing.

Similar Species

• Chipping Sparrow (Spizella passerina): Often confused due to its rufous cap, but it has a bold black line running directly through the eye, a distinct white eyebrow stripe, a completely unspotted breast, and a dark bill. Chipping Sparrows also migrate south early, rarely overlapping with wintering American Tree Sparrows.
• Field Sparrow (Spizella pusilla): Has a bright white eye-ring, a pink bill, lack of a breast spot, and overall warmer, rufous-toned plumage without the stark gray facial contrast.

Breeding Range

During the short summer months, the American Tree Sparrow breeds in the subarctic tundra of Alaska and northern Canada. They favor the "tree line" ecotone, where stunted spruce, willows, and birches give way to open, mossy ground.

Wintering Range & Migration

They are strictly migratory. As winter approaches, the entire population moves south into southern Canada and across the northern and central United States.

During this season, they occupy open areas including:

• Weedy fields and overgrown pastures
• Brushy fencelines and roadsides
• Forest edges and marsh borders
• Suburban backyards, gardens, and parks with dense woody cover.

Feeding and Diet

During winter, the American Tree Sparrow consumes a diet consisting almost exclusively of grass and weed seeds, along with occasional berries. They forage primarily on the ground in small, social flocks. They have a characteristic feeding method where they jump up to scratch or buffet seed heads on low-hanging weeds to shake seeds loose onto the snow. At feeders, they readily accept sunflower seeds, millet, and cracked corn.

Vocalizations

Their winter call is a high-pitched, metallic "teet" or a musical double-noted "tweedle-eet" that helps flocks keep in contact while foraging. In early spring, males begin singing a beautiful, sweet song that starts with several high, clear whistling notes and descends into a varied, rapid warble.

Nesting

Nests are typically built on the ground, well-hidden under low shrubbery, tussocks of grass, or low birch branches, and occasionally placed very low in a shrub. The female constructs a thick, sturdy cup of moss, grasses, bark, and twigs, lining the interior with fine grasses and ptarmigan feathers to insulate against the arctic chill.