American Tree Sparrow (Spizelloides arborea) by Kim Ehn
While most people think Dark-eyed Juncos are the “sign of winter” birds, I believe the American Tree Sparrow comes to Indiana with the cold winter weather right behind it. They migrate in flocks at night, arriving in Indiana during October through December. Birders have reported 100-150 birds in a single day in Newton and Greene Counties. Undaunted by winter blizzards, these sparrows will fluff out their feathers to trap more warm air while looking so plump.
The American Tree Sparrow is distinguished by its dark, rufous crown and rufous stripe that extends behind the eye, the bi-colored bill with a dark upper mandible and yellowish below, and a dark “smudge” in the center of its grayish breast. In contrast, the Chipping Sparrow has a black line through the eyes, a pinkish bill, and lower numbers observed in Indiana during the winter.
Foraging for seeds and fruits, the hardy American Tree Sparrow will scratch at the ground, visit bird feeders and even use their wings to release seeds from grasses and weedy forbs. While they also gather and eat catkins and dried berries, you may find them feeding in gardens or perched on low-growing shrubs and goldenrod stalks. Each day, they need to take in 30% of their body weight in food to make it to the next sunrise.
In late spring, males will start singing a high, sweet whistle. Many females travel farther south than the males, wintering in areas from the east coast to just west of the Rocky Mountains. The migration back to the breeding grounds in Alaska and Canada is thought to coincide with spring snow melt in the far North. In Indiana, the American Tree Sparrows are usually gone by April.
Photo by Shari McCollough