Mimus polyglottos
northern mockingbird

Northern mockingbirds are distributed throughout North America, including Canada and Mexico. In fact, sightings have been reported as far off the coast as Hawaii (where they were introduced). However, northern mockingbirds are most commonly found in the southern regions of the United States and are most often sighted in Texas and Southern Florida. They breed from northern California, eastern Nebraska, southern Ontario and Atlantic Canada southward to southern Mexico. (Rylander, 2002; Texas Parks and Wildlife Department, 2003; Wild Birds Forever, Date Unknown)

Northern mockingbirds prefer open areas and forest edges. They are commonly found in residential areas, farmlands, roadsides, city parks, open grassy areas with thickets and brushy deserts. They require a tree or higher perch from which they can defend their territories. Northern mockingbirds occupy similar habitat year-round. (Nature of New England, 2003; Rylander, 2002; Texas Parks and Wildlife Department, 2003)

Northern mockingbirds are medium-sized birds with long legs and tails, and short, rounded wings. Males are larger than females, ranging from about 22 to 25.5 cm in length and averaging 51 g. Females range from 20.8 to 23.5 cm long and weigh an average of 47 g. Northern mockingbirds have gray-brown upperparts, with a large white patch on each wing and white outer retrices that are conspicuous in flight. Their black bills are long and somewhat decurved. Males and females are similar in appearance, with the exception of difference in size and slightly darker tail feathers on females. Juveniles are similar to adults, but have brown spots on their underparts. (Derrickson and Breitwisch, 1992; Rylander, 2002)

Northern mockingbirds have been known to live up to 8 years in the wild. Captive northern mockingbirds have lived up to 20 years. (Derrickson and Breitwisch, 1992; Sprott and Mazzotti, 2001)

Northern mockingbirds are perhaps best known for their remarkable singing abilities. This species can perform at least 39 songs as well as 50 call notes. Northern mockingbirds also have the ability to mimic sounds such as dogs barking or the songs of other birds.

Northern mockingbirds are solitary and territorial. During the nesting season, they are often very aggressive; they often attack other animals in defense of their territory, including animals as large as cats, dogs and humans

Northern mockingbirds are diurnal. They are also partially migratory. Most individuals that breed in the northern part of the range migrate south for the winter. Those that nest in the southern part of the range are typically year-round residents. (Derrickson and Breitwisch, 1992; Texas Parks and Wildlife Department, 2003)

Home Range

We do not have information on home range for this species at this time.

Northern mockingbirds communicate primarily using song. They can perform at least 39 different songs as well as 50 other call notes. They also have the ability to mimic certain sounds such as dogs barking, pianos, sirens and squeaky gates. Song is also an essential part in mating. Males use their song to attract mates and to mark their territory. They sing often, both during the night and day.

Northern mockingbirds also use visual cues to communicate. For example, males perform a “flight display” to attract and court a mate (see Reproduction: Mating Systems). This display integrates auditory and visual methods of communication. (Derrickson and Breitwisch, 1992; Rylander, 2002; Sprott and Mazzotti, 2001)

Northern mockingbirds are omnivores. Their primary food sources are insects, berries and seeds. Insects they eat include beetles (order Coleoptera), ants (order Hymenoptera), grasshoppers (order Orthoptera) and spiders (order Araneae). Plants that are included in their diets are: holly, mulberries, raspberries, dogwood, brambles, grapes and figs. They also eat earthworms, and occasionally small crustaceans and small lizards.

Northern mockingbirds usually forage on the ground or while perched in a tree or shrub. They obtain water by drinking from puddles, river and lake edges and dew and rain droplets that collect on vegetation. (Derrickson and Breitwisch, 1992; Gough, Sauer, and Iliff, 1998; Holoweb, 2001; Rylander, 2002; Wild Birds Forever, Date Unknown)

Adult northern mockingbirds are vulnerable to predation by sharp-shinned hawks, screech owls, scrub jays and great horned owls. Incubating females are also occasionally killed by snakes.

Northern mockingbird eggs and chicks are vulnerable to predation by blue jays, fish crows, American crows, snakes and squirrels.

When predators approach the nest, adults give alarm calls. Adults often also mob predators that enter a territory, sometimes striking them. (Derrickson and Breitwisch, 1992)

Northern mockingbirds play an important role as seed dispersers. They also impact populations of the insects they eat. Northern mockingbirds host several ectoparasites, including blowfly larvae (family Calliphoridae), fleas and mites. Finally, three cowbird species (genus Molothrus) brood parasitize northern mockingbirds. This means that these cowbird species lay eggs in the nests of northern mockingbirds that then raise the cowbird chicks. (Derrickson and Breitwisch, 1992; Sprott and Mazzotti, 2001)

Northern mockingbirds are often thought of as a nuisance because of their nocturnal singing, which may keep people up at night. Gardeners and farmers may also dislike these birds which often feed on fruits and vegetables, potentially damaging their crops. (Texas Parks and Wildlife Department, 2003)

Northern mockingbirds eat insects that humans often consider to be pests. These include beetles, ants, wasps and grasshoppers. They also disperse the seeds of many plants. Humans often study their unique behaviors and vast vocal repertoire. (Sprott and Mazzotti, 2001; Texas Parks and Wildlife Department, 2003)

Northern mockingbird populations are extensive and are not currently of conservation concern. There are an estimated 45,000,000 northern mockingbirds worldwide. This species is protected by the US Migratory Bird Treaty Act. (Karl, 2000)