Bird Database

American Tree Sparrow

(Spizelloides arborea)

State of the Birds
At a Glance

Habitat

Migration

Short distance

Population

Decreasing

Threats

Habitat loss and fragmentation, Climate change

Conservation Actions

Maintain a bird friendly yard

American Tree Sparrow

(Spizelloides arborea)

Despite its name, the American Tree Sparrow is a bird of the arctic, where trees are few, far between, and stunted. It nests near treeline in shrubby areas of alder, willow, birch, and spruce, as well as farther out on the tundra if there are a few taller perches. Because of this remote breeding range, the species’ nesting biology is not well understood. In the winter, however, it can be a familiar sight in weedy fields, shrubby edges, and residential yards with feeders, and sometimes travels in large flocks. There has been a fair bit of study of tree sparrows in winter, particularly related to metabolism. One such study found that they can fast for an average of 30 hours. Another fun fact: tree sparrows often roost communally under the snow!

Although still abundant, American Tree Sparrows have declined by roughly 50% in the last 50 years. Because their ecology is little studied, we don’t have a good explanation for this at present. One hypothesis is that intensified agriculture in the Midwest and Great Plains (where the species reaches its highest winter densities) has eliminated much of the weedy and shrubby habitat needed by wintering birds. Development and forest maturation have probably had a similar effect here in the Northeast. There is also the possibility that climate change could be affecting their nesting habitat or breeding success.

The American Tree Sparrow is sometimes called the “winter chippy” because it has a rusty cap like the Chipping Sparrows that nest throughout New Hampshire, and this similarity is sometimes a source of confusion. Chipping Sparrows are not expected in the state between November and April, and thus barely overlap with their larger relatives. Note also that Chipping Sparrows lack their reddish cap in the winter and have a very different face pattern. They have buffy and dark brown stripes above and through their eyes, respectively, while those same areas in American Tree Sparrow are gray and rusty. The tree sparrow also has a dark spot on its breast and a yellow lower bill. The only time you really have a chance of seeing the two species together is in November, when lingering Chippings and early trees may join other sparrows in loose flocks in weedy fields and shrubby edges.

Seasonal Abundance

Relative abundance based on eBird data. Numbers indicate likelihood of finding this species in suitable habitat at a given time of year, not actual numbers encountered.

American Tree Sparrow
Range Map

Information for the species profiles on this website was compiled from a combination of the sources listed below.

  • The Birds of New Hampshire. By Allan R. Keith and Robert B. Fox. 2013. Memoirs of the Nuttall Ornithological club No. 19.

  • Atlas of the Breeding Birds of New Hampshire. Carol R. Foss, ed. 1994. Arcadia Publishing Company and Audubon Society of New Hampshire

  • Birds of the World. Various authors and dates. Cornell Laboratory of Ornithology.

  • Data from the Breeding Bird Survey

  • Data from the Christmas Bird Count