Song Sparrow

A Song Sparrow is a streaky brown sparrow, a little smaller than a Dark-eyed Junco and a little larger than a Chipping Sparrow. Look for thick brown streaks on a white chest and flanks, often running together into a dark spot in the middle of the breast; a grayish face with a russet stripe through the eye; and a broad dark stripe down each side of the throat, the mustache (or malar) stripe.¹

The tail is long and rounded, not notched, and the bird pumps it down as it flies, usually in short, low, fluttering flights from one bush to the next. A singing male perches upright on an open twig, often leaning back as he sings.¹ The bill is short, stout and brown, and the legs brown to pinkish brown.²

Size depends on where it lives: from 4.7 to 6.7 inches (12-17 cm) long and from 0.4 to 1.9 oz (12-53 g), the biggest and heaviest in Alaska.

Few North American birds vary as much. Scientists recognize 24 subspecies, and up to 52 have been named.^{3, 1} They fall into a few broad types: small, brown, black-streaked birds from the Great Basin to the Atlantic; large, dark birds with blurry streaks in Alaska and the Pacific Northwest; small grayish birds in California west of the Sierra; small, pale, rufous-streaked birds in the desert Southwest; and black-spotted, white-throated birds on the Mexican Plateau.

The pattern follows the climate: darker where it is humid, paler where it is dry, and bigger in the north. Song Sparrows on Alaska's Aleutian Islands are about one-third longer and twice as heavy as eastern birds. For all that, the genetic differences between regions are small; birds moving between populations may keep them alike underneath, while local conditions favor the local look.¹

Males and females look alike. Males are a little larger on average, but sizes overlap so much that 5-10% of birds cannot be sexed by size, even in the hand. The surest clue is behavior: the bird singing from the top of a bush is almost always a male, because females sing only rarely. More: male vs female Song Sparrows.

Juveniles, this year's young, are drabber and buffier than adults, with fuzzier streaks, weaker head stripes, no rusty tones on the crown and a buff eye-ring. On Mandarte Island in British Columbia, young hatched in March and April often look like adults by mid-September.

House Sparrow. About the same size but stockier, with a stouter bill, a shorter tail and an unstreaked breast: the male has a black bib, the female is plain gray-brown below. Side by side: Song Sparrow or House Sparrow?

Lincoln's Sparrow. Smaller, with finer streaks on a buff-washed breast. An adult Song Sparrow is more heavily streaked, with no buff wash, though a juvenile Song Sparrow in summer can look buffy, with finer streaks.

Savannah Sparrow. A shorter, notched tail, yellowish lores (the spot between the eye and bill), a finer bill, and usually in open fields rather than brush.

Fox Sparrow. Bigger, with a plainer face, triangular spots below and a less streaked back.

Vesper Sparrow. White outer tail feathers, best seen as it flies, a notched tail, and a chestnut shoulder patch that is often hidden.

Female House Finch. A plain grayish-brown face with no head stripes, and thick, blurry streaks below.

The song gives the bird its name, and males are recognized by it everywhere. It usually starts with a few loud, well-spaced notes and runs on into buzzes and trills, in 2 to 6 phrases, over 2 to 4 seconds. Songs differ from place to place, so the Song Sparrows you hear on a trip may not sound quite like the ones at home.¹

Each male has a repertoire of about 5 to 13 song types. He repeats one type 5 to 15 times, then switches to another. Young males learn most of their songs from older males, and after their first year they keep the same repertoire.²

Song Sparrows sing in much of their range all year, most of all just before and during breeding, and again for a few weeks after the fall molt. In Margaret Morse Nice's classic Ohio study, unmated males sang 180-200 songs an hour, and a male whose mate had disappeared sang 2,305 songs in 15 hours.

A sharp chip, "tchunk", is the alarm call of both sexes. On Mandarte Island a higher "tik" was given when hawks flew over. Young and subordinate birds give a soft "tsip", and females have a harsh chatter for their mate or a rival female. Listen to seven recordings and see the songs drawn as spectrograms: Song Sparrow song and calls.

Song Sparrows live across most of North America, from the Aleutians, Alaska and much of Canada south through most of the US to Mexico. Look in brushy, shrubby and weedy places, often near water: streamsides, marsh edges, overgrown fields, hedgerows, forest edges, backyards and parks. Some live in salt marshes.⁴ In the Aleutians they live among beach grass and boulders.²

They rarely stray far from cover, usually less than 33 ft (10 m). In spring and summer they are among the most conspicuous sparrows, because the males sing from open perches; in winter, especially in the Southeast, they are often found with other sparrows such as White-throated Sparrows, at field edges and shrubby borders.

Listen first: a bright song that starts with a few loud notes, from the top of a shrub or fence. Then watch the edge of the brush for a streaky sparrow that flies low to the next bush, pumping its tail, or scratches on the ground under cover. In a yard, check the ground under feeders that are close to shrubs.

Some do, some do not. Over most of the US they are present all year, but on the northern Plains, in the upper Midwest and in northern New England they are mainly summer birds. In the Gulf states, Texas, Oklahoma, Kansas, Arkansas, New Mexico, South Carolina and Florida they come mostly for the winter, from about October to April, though some breed in the north of New Mexico, Kansas, Alabama and South Carolina. Many coastal, southwestern and southern populations stay put, and so do the birds of Alaska's Aleutian Islands and Peninsula.

In the East, the birds that breed farthest north are the most likely to migrate, and they winter farthest south, passing over birds that stay. Banded adults that moved more than about 155 miles (250 km) traveled about 530 miles (850 km) on average. Spring migration runs mainly from mid-March to mid-April, and fall migration in September and October. In Nice's Ohio study, about half the males and 80% of the females migrated each year, and 90% of males and 98% of females kept the same habit for life.²

Song Sparrows are very rare visitors to Europe: the British Isles had six records up to 1990, all in spring.

Insects in summer, seeds in winter. In a classic study of 401 stomachs from across the US, plant food made up about two-thirds of the diet over the year, but from May to August animal food was more than half. In the Northeast and Pacific regions, plant food made up 86% of the diet in winter and 92% in fall.²

The insects include beetles, grasshoppers and crickets, caterpillars such as cutworms and armyworms, ants, wasps, bugs and flies, along with spiders, snails and earthworms. The seeds are mostly weeds and grasses: smartweed, bristlegrass, ragweed, crabgrass, pigweed and knotweed. In July berries make up about 8% of the diet: blackberries, raspberries, strawberries, blueberries, mulberries and wild cherries. Coastal birds also take small crustaceans and mollusks.

Most feeding is on the ground under cover. A Song Sparrow scratches with both feet at once, a quick double hop, forward and back, that drags the leaf litter aside, and it also picks insects from leaves, catches them in the air and wades in very shallow water.

Song Sparrows often come to feeders, but they feed low. Project FeederWatch lists black-oil and hulled sunflower seed, cracked corn, millet, milo, nyjer, peanut hearts and safflower for Song Sparrows, offered on the ground or on a platform feeder, the two feeder types it lists for them.⁵ In feeding tests, millet was the seed they preferred and husked fastest.

Put feeders close to good cover, as Song Sparrows rarely feed far from it.⁴ Cats are the catch: domestic and feral cats kill Song Sparrows, and birds that nest near homes and feed at ground-level feeders may be at risk.

In the Northeast in winter 2021-22, Song Sparrows came to 52.69% of FeederWatch sites, the 16th most widespread feeder bird there.⁶

Song Sparrows nest on the ground under a tuft of grass or a shrub, or low in a bush, often near water, and sometimes in flower beds close to houses. The female builds a sturdy cup of grass, weed stems, leaves and bark in about 4 days and lays usually 3 to 5 eggs, pale blue or greenish and spotted brown. She incubates them for about 12 to 14 days, and both parents feed the chicks, which leave the nest at about 9 to 12 days old.

Pairs raise two or three broods a year, and where the birds are resident some make up to seven nesting attempts in a season. Song Sparrows are among the Brown-headed Cowbird's favorite hosts. More: Song Sparrow nests, eggs and young.

Song Sparrows are territorial. Where they live all year, both males and females hold territories in every season; elsewhere males claim their patches on return in spring, and singing picks up again in September and October after the molt. Birds without territories, called floaters, wait for a vacancy: in one study, removed males were replaced within 12-72 hours.

Most pairs are socially monogamous, but at least 15% of young are fathered by a male other than the female's mate. Fights that come to blows are rare; disputes are settled with song, puffed-up threat displays and chases. Song Sparrows hold their own against bigger birds: they won 99% of 251 encounters with White-throated Sparrows, though Fox Sparrows push them aside at feeders.²

Song Sparrows are a model species for field biology. In the 1930s Margaret Morse Nice followed individually banded Song Sparrows on the Olentangy River floodplain in Ohio for years, and her studies set the standard for watching marked birds in the wild. On Mandarte Island in British Columbia, about 15 acres (6 ha), the Song Sparrows have been banded and followed for decades, showing how food, cowbirds, inbreeding and weather drive numbers.

One more recent experiment stands out. When researchers protected wild Song Sparrows' nests from real predators and played recordings of predator calls, the fear alone cut the number of young raised per year by 40%.⁷

About half of adult Song Sparrows survive from one year to the next (45-63% in most studies), and only about 20-26% of young birds live to their first birthday. The oldest birds in long-term field studies were 8-9 years old.

The longevity record is 11 years, 4 months: a bird banded as an adult in Colorado in 1963 was caught and released there again in 1973.⁸

Nests are the weak point. Snakes, raccoons, squirrels, mice, crows, cowbirds and cats all take eggs or chicks. Adults are caught by Cooper's and Sharp-shinned Hawks, owls, harriers, shrikes, foxes and cats; on Mandarte Island one Cooper's Hawk took about 20% of the population in a single winter. Song Sparrows give alarm calls at cats, raccoons, squirrels and foxes, and give a high "tik" and hide when a hawk passes over.

The Song Sparrow is common and widespread, with a breeding population estimated at about 130 million, and it is of Least Concern worldwide. Numbers are falling, though: the North American Breeding Bird Survey found a decline of about 27% between 1966 and 2019.¹ In survey data up to 2000, the losses were concentrated in the East, especially New England, while numbers rose in parts of the Southwest.² Partners in Flight rates it 8 out of 20 for concern, which is low.

Some local populations have done badly. Song Sparrows have vanished from Santa Barbara and San Clemente islands off California after habitat loss, introduced hares and fire, and the salt-marsh subspecies of San Francisco Bay declined as the tidal marshes were lost. Habitat can come back: on Arizona's upper San Pedro River, Song Sparrows increased 50-fold after cattle were removed and the streamside thickets grew back. The Song Sparrow is protected under the Migratory Bird Treaty Act.⁹