Sparrow is the name given to several unrelated groups of birds. Sparrows are classified in 3 families: Emberizidae, which includes New World sparrows; Estrildidae; and Passeridae, which includes the familiar house sparrow. About 25 species of the family Emberizidae regularly occur in Canada.
Sparrows are small to medium-sized, ranging in length from LeConte's sparrow (Ammodramus leconteii), as small as 11 cm, to the spotted towhee (Pipilo maculatus), up to 21 cm.
Generally, sparrows have dull plumage with distinctive head markings; the exceptions are the brightly coloured towhees and the sharply patterned juncos. Males and females of most species are similar in size and plumage; for example, male and female song sparrows (Melospiza melodia), widespread in Canada, are virtually indistinguishable by plumage alone.
Usually, only males sing; thus a singing song sparrow is almost certainly male. Songs differ considerably among species. Lark sparrows (Chondestes grammacus), of dry fields with scattered bushes and trees, sing long, melodious songs containing many trills. White-throated sparrows (Zonotrichia albicollis), of coniferous and mixed forests, utter songs of pure tone; one rendition, paraphrased as "Oh sweet Canada Canada Canada," has given them the local name Canada bird. Grasshopper sparrows (A. savannarum), of grassy fields in extreme southern Canada, give tuneless, insectlike reelings. Henslow's sparrow (A. henslowii), of weedy fields of southern Ontario, gives one of the poorest vocal efforts of any bird, a hiccoughing "tsi-lick."
Primarily ground feeders, sparrows eat mostly seeds, although insects are eaten in summer. Adults of most species feed insects to young.
All species of sparrows in Canada are migratory to some extent. American tree sparrows (Spizella arborea) nest in scrub willow of the Subarctic and winter in southern Canada and northern US. Clay-coloured sparrows (S. pallida), of brush-covered prairies, winter in Mexico. The Ipswich sparrow (Passerculus sandwichensis princeps), a well-marked subspecies of the widely distributed savannah sparrow (P. sandwichensis), breeds only on Sable Island and winters on the Atlantic seaboard.