Why Do Mockingbirds Sing at Night? Unmated Males Explained

The short answer: a male looking for a mate

For a northern mockingbird, song is a way of advertising. A male sings to tell rival males that a territory is taken and to tell females that he is available. Studies of mockingbird singing have found that males without a mate sing far more than paired males: they sing more bouts, turn to face more directions, choose higher perches and add more song-flight displays, in which the bird flutters up into the air while singing and drops back down.

Night singing is the most extreme version of this effort. An unpaired male may sing for hours after dark, night after night, with a long medley of his own phrases and imitations of other birds. When a female settles in his territory and the pair begins nesting, his nighttime performances usually fade quickly.

When do mockingbirds sing at night?

Night singing is a breeding-season behavior. Males begin singing in late winter, and night singing is most common from about March through June, sometimes into July or August where pairs raise several broods. Each time a nesting attempt fails or a female leaves, a male may start singing at night again.

In fall, mockingbirds sing again to defend winter territories around fruiting shrubs, but this autumn singing is mostly by day, and both males and females take part.

The darkest hours are not always the busiest. Many people notice that night singing is strongest on nights with a bright moon, and in towns where streetlights, porch lights or parking-lot lights keep the area lit.

Why sing in the dark?

Singing at night has some real advantages for a bird trying to attract a mate:

• Less noise. At night there is less traffic and fewer other birds singing, so a song carries farther and is easier to hear.
• Females on the move. Many songbirds travel at night, so a male singing after dark may reach a female that is moving through the area or still searching for a territory.
• Time to show off. A long, varied night performance may signal to a female that a male is healthy and has energy to spare.

Light also matters. Researchers have found that mockingbirds nesting near artificial lighting in residential areas can feed their nestlings into the night, which shows how much city lights extend their active day. Light from streetlights may encourage some males to keep singing long after dusk.

Is it always an unmated male?

Mostly, but not always. Mated males occasionally sing at night too, especially between nesting attempts or when a neighboring male is singing. Some mated males also sing to attract a second female, since mockingbirds are socially monogamous but not always faithful.

What is very unusual is a female singing at night. Females do sing, but softly and mainly in the daytime in fall and winter, or occasionally in spring when the male is away.

Other birds that sing at night

Mockingbirds are not the only night singers. In Europe, the common nightingale is famous for singing after dark, and as with mockingbirds, it is mostly unpaired males that sing through the night. The European robin often sings near streetlights in towns, as described in why do robins sing at night?

In North America, American robins and some sparrows occasionally sing in the dark around bright lights. Owls and nightjars, such as the whip-poor-will and chuck-will’s-widow, are truly nocturnal and call at night as part of their normal routine. If the night song you hear is a long, changing medley with each phrase repeated several times, it is almost certainly a mockingbird.

Myths and facts about mockingbird night singing

Myth: a mockingbird singing at night is sick or confused. Night singing is normal breeding behavior, not a sign of illness. The bird is healthy enough to spend a lot of energy singing.

Myth: mockingbirds sing at night all year. It is mainly a spring and early-summer behavior and is rare in fall and winter.

Fact: night songs are often full of imitations. A night-singing male may run through dozens of song types, including copies of cardinals, wrens, jays and frogs. To learn how large a mockingbird’s repertoire can grow, see how many songs can a mockingbird sing?

Fact: the bird is protected. Northern mockingbirds are protected under the US Migratory Bird Treaty Act, so it is illegal to harm them or disturb an active nest. In most cases the singing ends on its own once the male finds a mate, usually within a few weeks. For more on why many birds sing hardest around sunrise, see why do birds sing in the morning?