The Superb Lyrebird: the Australian bird that mimics chainsaws, cameras and every bird in the forest

Stand in the right stretch of wet eucalyptus forest in southeastern Australia on a winter morning and you may hear what sounds like a full dawn chorus compressed into a single bird. Kookaburra, crimson rosella, grey fantail, eastern yellow robin: all present, all apparently calling at once, all emerging from the same source. Then a sound that does not belong: the rising whine of a chainsaw, or the staccato click of a camera motor drive. The superb lyrebird is performing, and it is using your world as its material.

What a superb lyrebird looks like

The lyrebird is roughly the size of a pheasant, a large, ground-dwelling bird with a surprisingly plain body given the fame of its voice and tail. The plumage is rufous-brown with chestnut tones on the wings, darker above and paler below. Seen walking through leaf litter, it looks like a large, long-legged thrush. Nothing prepares you for the tail.

In a displaying male, the tail has three types of feathers. Two long outer filaments curve outward at the tips in a lyre shape, giving the bird its name. Inside these are 12 lacy, filament-like feathers called lyrates. Between them, two broad, ribbon-like median feathers frame the whole structure. Fanned forward over the head during display, the tail becomes a translucent silver-white cage. The total tail length can exceed 55 cm, longer than the bird's entire body.

Females and young males are smaller and lack the elaborate outer feathers, though they share the same extraordinary vocal ability.

The syrinx: the instrument behind the mimicry

Most birds have a syrinx (the avian equivalent of a larynx) controlled by two muscle pairs. The lyrebird's syrinx is controlled by five pairs, making it one of the anatomically most complex vocal organs of any known bird. This allows the lyrebird to control multiple independent sound sources simultaneously, producing the harmonic richness of a flute, the percussive crack of a whip or the frequency-modulated sweep of a chainsaw, all from the same throat.

The mimicry is not reflex. It is learned. A young male listens to sounds in its environment over its first few years of life and practices, adding new sounds as it encounters them. Songs are culturally transmitted: males learn partly from their fathers, partly from neighbouring males in a local dialect, and partly by direct environmental sampling. A lyrebird that lives near a logging operation will add chainsaw sounds; one in a busier habitat will add car alarms and camera shutters.

Accuracy is striking. Researchers playing back recorded lyrebird mimicry to experienced birdwatchers have found that trained observers regularly misidentify the source species from the lyrebird's replica. The playback quality is high enough to elicit territorial responses from real birds.

Why evolve mimicry?

Mimicry in lyrebirds is primarily a sexual display. Males display from cleared mounds (up to 1 m high, built from scratched earth) in the understorey during winter, the breeding season in southeastern Australia. A displaying male fans the tail forward, vibrates it, and sings continuously for periods of up to an hour.

The song mixes mimicry with the male's own species-specific calls. Females observe and assess. A male that has accumulated a larger, more accurately reproduced repertoire signals age (it takes years to learn this many sounds), good health and a territory with enough variety to encounter many sound sources. These are honest signals of fitness: a younger or less healthy male simply has fewer resources for sustained display and a shorter, less varied repertoire.

Some researchers have proposed a second role: that males use alarm mimicry (kookaburra and cockatoo alarm calls) to startle females during mating, prolonging contact time. The evidence for this is debated, but if accurate it adds a distinctly manipulative layer to the most elaborate performance in Australian bird life.

Foraging: the other extraordinary adaptation

What the lyrebird does when it is not singing is almost as remarkable. It forages entirely in leaf litter, raking through deep accumulations of dead leaves and bark with oversized, powerful feet. In a good-quality forest, a single lyrebird may turn over 11 cubic metres of leaf litter per day in its search for earthworms, beetles, insect larvae, spiders and centipedes.

This makes it a significant driver of nutrient cycling in wet Australian forests. Where lyrebirds are present, litter decomposition rates are measurably higher and soil carbon and nitrogen distributions differ from lyrebird-free forest. The bird is, alongside the beaver and the earthworm, one of the clearer examples of a single animal species shaping the physical properties of its ecosystem.

How rare is the superb lyrebird?

The Kaught catalog rates the superb lyrebird at Rare tier, two diamonds. Lyrebirds are secretive, move quietly through dense understorey and detect human observers at considerable distance, at which point they stop singing and melt away. Hearing one is common in suitable habitat; seeing one in display is far less so.

The species is restricted to wet eucalyptus forest in a relatively narrow belt of southeastern Australia. Outside this zone, no sighting is possible. Within it, the best chance is a cool, still morning in June or July, moving slowly and waiting at the edge of a gully or cleared mound area.

For another bird with an extraordinary relationship with sound, see grey heron. For more on Australia's wildlife, compare with Andean condor, another large bird shaped by a very specific habitat.