The American Tree Sparrows come with the first cool breeze in October, arriving upon a bounty familiar to both sparrows and restoration practitioners—seed. On any given day in October, we could probably collect seed from 100 different plant species at Faville Grove, though 30 is probably the ceiling within reach. The birds might get to more species, pecking along indiangrass, pilfering the round-headed bushclover, and piling up a belly full of yellow coneflower.
American Tree Sparrows almost always find themselves in the background; whether flocking with Dark-eyed Juncos or other sparrows. Their fall arrival is a footnote to an encroaching winter, to the mostly departing Swamp, LeConte’s, Fox, White-crowned, White-throated, Nelson’s, and Lincoln’s Sparrows. A prelude to the arriving crossbills, grosbeaks, and various winter finches.
Tree sparrows breed in the Arctic along the tundra line. They generally prefer open areas with lots of grassy cover and weeds, so the “tree” part of their name is really a misnomer. In order to survive the winter, American Tree Sparrows need to eat enough each day to equal roughly one third of their body weight. That means a flock of 100-200 sparrows could eat two to three pounds of seed. We often see their inventive behavior of beating seeds off of plants with their wing strokes, to feast on the ground. If you flush a full flock of them and investigate the snow-covered ground nearby, you’ll likely notice scattered seed and wing prints.
A small flock of American Tree Sparrows pick seeds from the ground on the side of a road (photo by Kaitlin Svabek).
For me at least, American Tree Sparrows come to the forefront when I’m spreading seed in late fall and early winter. We typically like to do this later in November once the blackbirds have migrated, but there’s no getting around the hungry sparrows. For this reason, we try to spread seed before an incoming snow storm, so the seed gets covered, or when the snow will soon melt.
In December, I was spreading seed at Fat Goose Prairie, and nearing the end of the day it looked like I got great coverage. But around 3:30pm I was sitting still on a bucket and could’ve snatched Tree Sparrows from the nearby snowbanks. Word had gotten out. Luckily, the next day was warmer and sunny, so I hope the seed incorporated into the soil, and the American Tree Sparrows could return to the background—the weedy spots of foxtail and mare’s tail—dissolving into a winter reserve.
Written by Drew Harry, Faville Grove Sanctuary land steward
Cover image: An American Tree Sparrow has a pale underside, dark spot on the chest, brown and rusty colored feathers on the wings and back, and a reddish cap and eyeline. The bird is perched in the snow and holding a thin twig (photo by Kelly Colgan Azar/Flickr Creative Commons).
