Northern Mockingbird (Mimus polyglottos): Facts and Songs

Appearance: how to recognize a mockingbird

At first glance the northern mockingbird looks plain. Its upperparts are soft gray, its underparts whitish to pale gray, and its wings and long tail are darker gray-black. Two thin white wing bars cross each wing, and the eye is pale yellow to greenish yellow, giving the bird an alert, slightly fierce look. The bill is thin, black and slightly curved at the tip.

The real field mark appears when it flies. Large white patches flash in the middle of each wing, and the outer tail feathers are white, so a flying mockingbird looks boldly black and white. Males and females look alike, although males are slightly larger. Young birds are browner, with spotted or streaked breasts and grayish eyes.

Mockingbirds have a curious habit called wing-flashing. While hunting on the ground, a bird lifts its wings in a jerky, two-step motion that shows off the white patches. Ornithologists still debate why: ideas include startling insects into moving, intimidating predators or simply displaying. Nobody has proved one answer.

Size

The northern mockingbird is a medium-sized songbird, about as long as an American robin but much slimmer and lighter.

Birds of the western subspecies are slightly larger and paler than those in the east, and Caribbean birds are a little smaller.

Habitat and range

The northern mockingbird lives across most of the United States, from coast to coast, south through Mexico to the Isthmus of Tehuantepec and through the Bahamas and Greater Antilles. It reaches southeastern Canada, especially the Maritime provinces and southern Ontario. It was introduced to Hawaii in the 1920s and is now established there. Lost birds have even crossed the Atlantic: a handful have turned up in Britain, including one that traveled from Devon to Northumberland in 2021.

It prefers open ground with scattered shrubs and trees. In the east, that means mowed lawns, parks, gardens, hedges, cemeteries and farmland edges; in the west, it also lives in desert scrub and chaparral. Short grass for hunting and dense bushes for nesting are the key ingredients, which is why suburbs suit it so well. Today more mockingbirds live in towns and cities than in the countryside. It avoids dense, unbroken forest.

Range expansion to the north

In the 1800s, mockingbirds were mainly southern birds. During the 20th century they spread north into Ohio, New York, New England and southeastern Canada. Milder winters, suburban gardens and especially the spread of multiflora rose, an introduced shrub whose hips provide winter fruit, are thought to have helped. Severe winters still push the range back at its northern edge.

Diet: what do mockingbirds eat?

Mockingbirds are omnivores, and their menu changes with the seasons. In spring and summer they eat mostly animal food: beetles, grasshoppers, ants, bees, wasps, caterpillars, butterflies, spiders and earthworms, and occasionally small lizards. Young in the nest are fed almost entirely on insects.

In fall and winter they switch largely to fruit: holly berries, mulberries, dogwood, blackberries, grapes, figs and rose hips. They also take garden fruit such as tomatoes and apples.

They hunt by running across short grass, pausing, flashing their wings and dashing at prey, or by dropping down from a perch. They drink from puddles and dew, and have even been seen drinking sap from freshly pruned branches.

Songs and mimicry

The mockingbird’s song is a long, loud stream of phrases, each usually repeated several times before the bird switches to the next. A single male may know somewhere between about 40 and 200 song types, and studies in Florida estimated up to about 200. Many are copies of other species, such as the northern cardinal, Carolina wren, tufted titmouse, blue jay and American robin, but mockingbirds also imitate frogs, crickets, dogs, squeaky wheels and car alarms. The full story is in how many songs can a mockingbird sing?

Males start singing in late winter and continue through summer, and both sexes sing in fall while setting up winter territories. Unmated males are the most persistent singers of all, and they often keep going through the night, especially under a bright moon or near streetlights, as explained in why do mockingbirds sing at night?

Besides song, mockingbirds have a few simple calls, including a harsh “chat” or “check” given when disturbed and a “hew” call aimed at predators and rivals.

Behavior and intelligence

Mockingbirds are territorial almost all year. In spring, males claim breeding territories and sometimes perform a “boundary dance” with a neighbor: the two birds face each other on the ground and hop from side to side until one gives up. In fall and winter, males and females often hold separate territories around fruiting shrubs and chase off other birds that try to feed there.

They are famously fearless. Mockingbirds will mob and dive at hawks, crows, snakes, cats and dogs, and neighbors may join in when a predator lingers. Some birds also attack people who come too close to a nest. In a well-known 2009 study in Gainesville, Florida, mockingbirds learned within a few days to recognize a person who had repeatedly approached their nest and flushed earlier for that person, while ignoring other people. More on this in why do mockingbirds attack people?

Reproduction and life cycle

The breeding season runs from early spring into late summer. Pairs are socially monogamous and may stay together for several seasons, although partner switching and extra-pair matings do occur.

Both parents build the nest, though the male does most of the work. It is an open cup of twigs lined with grass, rootlets, leaves or even plastic fibers, usually placed 1–3 m (3–10 ft) up in a dense shrub or small tree.

• Eggs: usually 3–5, pale blue or greenish with brown blotches.
• Incubation: about 11–14 days, by the female only.
• Nestlings: fed by both parents and leave the nest after about 11–13 days.
• Broods: two or three a year is common, sometimes four in the south.

After the young fledge, the male often looks after them while the female starts the next nest. Both sexes can breed when they are about one year old. Brown-headed cowbirds sometimes lay eggs in mockingbird nests, and the hosts reject some of these eggs, especially later in the season.

Lifespan

Most wild mockingbirds live only a few years, and few pass about 8. Banding records show that some survive much longer: the oldest known wild northern mockingbird was at least 14 years and 10 months old. In captivity, mockingbirds have lived up to about 20 years.

Eggs and nestlings are eaten by snakes, squirrels, American crows, blue jays, hawks and domestic cats. Adults are caught mainly by bird-hunting hawks and owls, including sharp-shinned hawks, screech-owls and great horned owls, but their alertness makes them hard targets.

Conservation status

The northern mockingbird is listed as Least Concern on the IUCN Red List. It has a very large range and a population in the tens of millions, although long-term surveys show a gradual decline in some regions.

In the 1800s, mockingbirds were popular cage birds, and so many were trapped for sale that they became scarce around some eastern cities. Protection under the Migratory Bird Treaty Act of 1918 ended the trade, and today it is illegal in the United States to capture, keep or disturb wild mockingbirds, their eggs or their active nests. Harsh winters, which kill birds at the northern edge of the range, and lead in urban soils are among the threats studied today.

Myths and facts

Myth: mockingbirds only copy other birds. Every mockingbird also sings its own original phrases, and many of its “imitations” are rough versions that other birds are not fooled by. Florida scrub-jays, for example, ignore mockingbird copies of their calls.

Myth: mockingbirds are a kind of thrush. Linnaeus first described the species as a thrush in 1758, but it belongs to its own family, Mimidae, together with catbirds and thrashers. Its closest relative is the tropical mockingbird of Mexico, Central and South America.

Fact: mockingbirds helped inspire Darwin. The mockingbirds Charles Darwin collected on the Galápagos Islands in 1835, close relatives of this species, differed from island to island, and they were among the observations that set him thinking about how species change.

Mockingbirds and people

The northern mockingbird is the state bird of Arkansas, Florida, Mississippi, Tennessee and Texas, more than almost any other bird; see the full list of US state birds. Thomas Jefferson kept pet mockingbirds in the White House, one of them named Dick.

It is also a literary symbol. In Harper Lee’s 1960 novel To Kill a Mockingbird, the bird stands for innocence: it harms no one and only makes music, so killing one is a sin. The traditional lullaby “Hush, Little Baby” and the 19th-century song “Listen to the Mocking Bird” also celebrate it. For many people in the American South and West, a mockingbird singing from a rooftop or TV antenna on a warm night is one of the defining sounds of spring.