american tree sparrow Spizelloides arborea

Hardy northern sparrow with plump body, small bill and long, thin tail. Note rusty cap and rusty (not black) eyeline, gray head and unstreaked grayish breast with dark smudge in center. Small flocks hop on ground, foraging for seeds, giving a soft, musical twitter. In winter, look for them in weedy fields with shrubs, forest edges, and marshes. Readily visit backyards. Rarely seen south of northern Canada in summer.