Birds of the Hackensack: Northern Mockingbird
By Ivan Kossak
Mockingbirds have earned their name as the most talented members of a bird family known as Mimic Thrushes. These birds imitate other birds' calls and have been known to mimic such varied noises as a child crying or a car door being slammed shut. Most birds vocalize as a way of announcing to others of their species that "this territory is taken". I have heard a theory that the Mockingbird's mimicry is used to advertise its territory to birds of whatever species it can imitate, thus eliminating; not only members of its own species, but a wide variety of rivals for the local food supply. In another unusual twist, both male and female Mockingbirds will sing, even in Autumn. In addition to its more melodious vocalizations, Mockingbirds also have a somewhat harsh call note, similar to that of blackbirds. Despite its name, the Northern Mockingbird is more common in the Southern United States than in our area and has only recently been expanding its range into New England. In the early years of the twentieth century, Mockingbirds were considered very rare in New Jersey. Their recent range expansion is sometimes attributed to the establishment of multiflora rose and other hedge type plantings in the Northeast. The "Northern" part of its name distinguishes this bird from its southern cousin, known as the Bahama Mockingbird. The Nothern Mockingbird's breeding range also covers the American Southeast, some of the Southwest, California and the Mid-Atlantic states. Generally not a migratory species, Mockingbirds will retreat from the northern fringes of its breeding range in the winter. Within its range, Mockingbirds are common to fairly common and can be found in a variety of habitats including suburban yards. They will often sing continually for long periods of time; repeating one song several times, then switching to another song that is then repeated several times. Northern Mockingbirds have been known to have as many as 200 different songs in their repertoire. Northern Mockingbirds are slender, measuring ten inches from its bill to the end of its long tail. They are mostly gray, with large white patches in otherwise black wings. They also have a black line that passes through a yellow eye. This can give the Mockingbird a somewhat fierce look to accompany its strongly territorial nature. The Mockingbird's tail is also mostly black with white outer feathers. The white of the wings and tail are evident in flight and often allows the Mockingbird to be identified at great distances. The Mockingbird will also flash its white wing patches in a territorial display while perched or on the ground. The Mockingbird's diet is varied, consisting of both insects and fruit. This allows the Mockingbird to survive in a given area all year long. So, the next time you hear a continual varied singing in your yard, keep an eye out for this popular resident of our watershed. You may identify your first Northern Mockingbird. |
Several times throughout the year, especially in the Spring,
any number of friends and acquaintances ask me about some blankety-blank bird
that sings all night long, keeping them awake. More often than not, that bird
is a Northern Mockingbird (Mimus polyglottos). Mockingbirds are aggressive in
maintaining and defending their territory; which may account for their extended
and versatile vocal antics.