Lyrebirds (Menuridae)

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Lyrebirds

(Menuridae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Menuridae


Thumbnail description
Large, brown, ground-foraging birds with strong legs and long tails, highly ornamental in the males

Size
28–42 in (71–107 cm)

Number of genera, species
1 genus; 2 species

Habitat
Forest

Conservation status
No species threatened or extinct

Distribution
Endemic to south-eastern Australia

Evolution and systematics

Lyrebirds probably originated in the Antarctic beech (Nothofagus brassii) forests and subtropical rainforests that covered much of Australia at the beginning of the Tertiary period. An early Miocene fossil species, Menura tyawanoides, has been described from Riversleigh in northwestern Queensland about 1,000 mi (1,700 km) from the northern limit of lyrebird distribution.

The open-floored nature of the beech forests (as can still be seen in New Zealand) was conducive to the evolution of visual courtship displays. The dense undergrowth of the wet sclerophyll forests and subtropical rainforests which replaced the beech forests probably necessitated the development of elaborate vocal displays.

When first discovered, the superb lyrebird was called a "native pheasant" and regarded as Gallinaceous, but it is now accepted that lyrebirds belong in the Passeriformes, and that their nearest relatives are the scrub-birds (Atrichornis). As of 2001 there was no unequivocal evidence linking the lyrebirds and scrub-birds to any other passerines. Proposed relationships with the bowerbirds (Ptilonorhynchidae) or with the tapaculos (Rhinocryptidae) have not been accepted.

The Records of the Australian Museum provide a detailed historical account of the systematics of the lyrebirds and scrub-birds. A meticulously planned series of studies on a single noisy scrub-bird specimen filled the 143 pages of that monograph. W. J. Bock and M. H. Clench summarize the research and conclusions reached. They accept that "the scrubbirds and lyrebirds form a monophyletic group of unknown affinities within the Oscines." They do not agree that the two genera form a single family as proposed on somewhat tenuous DNA hybridization grounds, and place them in separate families within a superfamily, the Menuroidea.

As of 2001, the most recent treatise on the systematics of Australian birds is The Directory of Australian Birds, published in 1999. The authors, R. Schodde and I. J. Mason, retain the two families, and recognize two species of lyrebirds, one with three subspecies.

Physical characteristics

Lyrebirds are among the largest of the songbirds, with male superb lyrebirds (Menura novaehollandiae) attaining a length of up to 39 in (100 cm), including the tail of 27 in (70

cm) and a weight of 2.2 lb (1 kg). Albert's lyrebird (Menura alberti) is slightly smaller. Lyrebirds have very strong legs and feet. The bill is short, sharp, and slightly down-curved.

Both species are brown, with Albert's being more rufous. The ornamental tail of the adult male distinguishes it from the female. Young males and females—"plain-tails"—are indistinguishable.

A lyrebird's tail has 16 rectrices (main feathers) and is best described using the terminology of Len Smith in his classic work, The Life of Lyrebird, published in 1988. An adult male has an outer pair of broad, fully webbed feathers ("lyrates"), a central very narrow pair ("medians"), and six pairs of "filamentaries" in which the barbs are separated except near the base. A young male superb lyrebird does not acquire a filamentary feather until at least his fourth year, and he is at least six years old before he gets a full set. Albert's lyrebird tail development is unknown.

Distribution

Lyrebirds are endemic to eastern Australia south from latitude 28° south, (between Brisbane and Melbourne) and up to about 100 mi (160 km) inland in some places. Albert's lyrebird occurs only in the northernmost 100 mi (160 km) of this range. Superb lyrebirds were introduced into Tasmania. A lyrebird fossil found at Riversleigh in northwestern Queensland shows that lyrebirds once extended much further north.

With both species, much habitat has been lost through European settlement, but the overall range has changed little in historical times.

Habitat

Lyrebirds are ground dwellers, though they rest off the ground during the day (several hours a day are spent in preening), and they roost high in the trees. They occur mainly in dense subtropical and temperate rainforest and wet sclerophyll forest, but superb lyrebirds extend into dry sclerophyll forest and even woodland where there is sufficient shrub growth to provide reasonable cover, but with areas of open ground for foraging.

Lyrebird nests are mostly built on the ground or on ledges of cliffs or large boulders, rarely in trees. Lyrebirds are poor flyers and nests are usually sited so that the female can glide downwards away from the nest if danger threatens.

Habitat requirements are trees in which to roost, sufficient vegetative cover to screen them from aerial and ground predators, an accessible year-round supply of invertebrate fauna for food in the leaf litter and surface soil, and suitable nesting sites.

Behavior

Noted ornithologist John Gould wrote that, of all the birds he had ever met, the superb lyrebird was by far the shyest and most difficult to stalk. Albert's lyrebird is even more wary, and so has been little studied. Observations of a population of superb lyrebirds that have largely lost their fear of people (in Sherbrooke Forest, Victoria, Australia) have provided much of what is known of lyrebird behavior.

Lyrebirds are sedentary, though individuals may wander away from their defended territories outside the breeding season, or to drink and bathe, which they do daily. They are generally solitary, but occasionally two or more may be seen together, mainly outside the breeding season.

Female superb lyrebirds also maintain territories and defend them against other females. Their territories overlap male territories but do not coincide with them. The situation with female Albert's lyrebird territories is unknown.

The three major components of male lyrebird vocalization are: loud territorial songs; a display song consisting largely of mimicry and aimed at attracting females; and sequences of peculiar rhythmic sounds—the so-called "pilik song" of superb lyrebirds, and the "gronking song" of Albert's lyrebirds. Lyrebird vocalizations are culturally transmitted from generation to generation. All males in a local area use the same territorial song or songs, for example, although there is great regional variation.

Male Albert's lyrebirds weave mimicked sounds into a fixed sequence, forming a stereotyped song about 40–50 seconds long that may be repeated many times without a break. All males in a local area have the same sequential song, clearly demonstrating that it is culturally transmitted. Superb lyrebird mimicry appears to come in random order.

Lyrebirds are renowned for their powers of mimicry and it is widely held that they mimic mechanical sounds of human origin such as axe-blows and mill whistles. However, they rarely do so in the wild, and never as part of their breeding season song. Both species regularly produce with the voice the sounds of feathered wings. Albert's lyrebirds mimic the brush-tailed possum (Trichosurus vulpecula), a local nocturnal marsupial. Out of the breeding season, lyrebirds mimic a greater variety of sounds on an irregular basis.

Lyrebirds learn to sing by copying older lyrebirds. This applies to choice of mimicry as well as the lyrebirds' own sounds, though obviously hearing the mimicked species enables them to keep the mimicry accurate. When superb lyrebirds were introduced into Tasmania they retained in their mimicry calls of eastern whipbirds (Psophodes olivaceus) and of pilotbirds (Pycnoptilus floccosus), neither of which occur there. For several decades these calls remained clearly recognizable but were no longer recognizable in 2001.

During winter, the species mimicked by the lyrebirds are not themselves breeding and are mostly silent, and so potential confusion of auditory signals is avoided.

Both species have a variety of alarm and threat calls. The principal alarm call, a loud piercing shriek, is common to both species.

Lyrebirds fly poorly but can leap vertically 6 ft (2 m) or more. They prefer to gain height by leaping and climbing in the vegetation. This way, and flying as little as possible, they can gain the forest canopy for roosting.

At dawn a lyrebird waits until there is enough light on the forest floor before descending from the roost. Mature males often spend this time in intermittent song. Once on the ground in the breeding season, those males that are defending territories first spend up to two hours singing and displaying before commencing to forage.

Feeding ecology and diet

Macro-invertebrate fauna, especially earthworms, insects, and insect larvae, are obtained by scratching in the leaf litter and upper layers of soil. Lyrebird legs, toes, and claws are long and powerful and can move surprisingly large stones and fallen branches in search of prey.

Lyrebirds require fresh water to drink and in which to bathe, preferring still pools to running water.

Reproductive biology

Lyrebirds have a dispersed lek mating system, each male having a number of display arenas within his large territory that is vigorously defended. Elaborate visual and vocal displays are used to attract females. Superb lyrebird males mate with any female they can attract, and do not form pair-bonds; Albert's lyrebirds are probably similar in behavior.

The female superb lyrebird undertakes all domestic duties, building the nest, incubating the single egg (rarely two), feeding the chick in the nest, and caring for it for up to nine

months after it leaves the nest. The nest is a large domed structure with side entrance, built of sticks with moss sealing the interstices; it is usually well camouflaged, and often has a platform at the entrance on which the female can stand. The nest is lined with feathers plucked by the female from her own body.

Incubation lasts six to eight weeks and the chick remains in the nest for another six weeks, so that the female remains close to the nest for about three months. As nests are often on or near the ground, nest hygiene is important; smell could disclose the location to a predator. The droppings of a lyrebird chick in the nest are produced in a gelatinous sac that the chick excretes directly to the bill of its mother. This she disposes of by burying or placing in a stream.

Both species breed in winter, approximately May to August, though superb lyrebird nests have been found with eggs as late as October. Winter breeding appears advantageous for superb lyrebirds in that most of their range has a winter rainfall, so that the chick is present when food is normally plentiful and more readily accessible.

Albert's lyrebirds also breed during the winter even though the different climatic pattern in their range results in the nestling being present during the driest time of the year. This suggests that the species may have evolved under different climatic conditions.

Conservation status

The extent of lyrebird habitat has been greatly reduced by human activities, first, and to an unknown extent, by Aboriginal fire management of the environment, probably over some tens of thousands of years, and second, by European settlement during the last two centuries. By the end of the nineteenth century, an extensive lowland area of rainforest in northern New South Whales, within the range of the Albert's lyrebird, had been cleared for dairying—a loss of some 185,000 acres (75,000 ha).

Both species of lyrebirds, however, appear secure with much of their remaining habitat being in conservation reserves. Some concern remains, nonetheless, for Albert's lyrebird because of its small total range. Some small isolated populations of both species are regarded as being at risk. Public opinion, as well as the law, now protects lyrebirds from hunting.

Cats, domestic and feral, dogs, and the introduced European red fox (Vulpes vulpes) are all potential predators, and have been a serious problem in some areas including Sherbrooke Forest. That population also suffers from deterioration of habitat. Lyrebirds need patches of open ground where they can forage. In the past, periodic bushfires ensured this by reducing the ground cover. As of 2001, however, the immediate proximity of residential development required total fire exclusion and increasing ground cover reduces foraging space.

Because they are so intensely shy, it is impossible to census a lyrebird population. Singing males can be counted, giving some indication of the extent and density of a local population, but that is all. And even this can be extremely difficult because of the dense vegetation and rugged terrain of most lyrebird habitat.

Significance to humans

The superb lyrebird has been extensively photographed and is widely regarded as "the" lyrebird. Although Albert's lyrebird was described as a species in 1850, it is so shy that it was not photographed in the wild until 1968, and as of 2001, only five people had photographed the display, three of them photographing the same individual. Thus it is the superb lyrebird that is of main significance to humans.

The name "lyrebird" arose from the resemblance of the tail of a male superb lyrebird to the shape of that ancient musical instrument. However, the bird rarely holds his tail in that position and then only briefly. The specific name, tyawanoides of the lyrebird fossil, is based on an Aboriginal name for lyrebird.

Lyrebirds of both species were occasionally eaten by European settlers, and male lyrebirds were extensively hunted for their ornamental tails until protective measures became effective early in the twentieth century. By 1920, populations were recovering.

In a few places where residential areas abut lyrebird habitat, superb lyrebirds forage in gardens and their vigorous scratching can be very destructive. As of 2001, Albert's lyrebirds were also invading gardens in one locality, notwithstanding their normal shyness.

The English ornithologist John Gould, who produced the first major publication on Australian birds, considered the superb lyrebird as the most appropriate bird to be the emblem of Australia: "it being not only strictly peculiar to that country, but one which will always be regarded with the highest esteem both by the people of Australia and by ornithologists in Europe, from whom it has received the specific appellations of superba, paradisea, and mirabilis."

While it has not achieved that distinction, it is the emblem of the National Parks and Wildlife Service of New South Wales, and it has appeared on Australian stamps. Interestingly, a superb lyrebird is featured on the logo of the Beaudesert Shire Council in Queensland, surely a tribute to that species' public renown, for the lyrebirds in that Shire are in fact all Albert's.

The song of the superb lyrebird was broadcast live from Sherbrooke Forest on July 5, 1931, and relayed to all Australian states. The first sound recordings (a gramophone record and sound film), made in Australia of a wild bird in its natural surroundings, were of a superb lyrebird in Sherbrooke Forest. The sound film was broadcast from Sydney to America in 1931.

Lyrebird song features in the music of the noted French composer Olivier Messiaen. One complete section of Eclairs sur L'Au-Dela (a major work commissioned by the New York Philharmonic) is based on superb lyrebird song Messiaen heard in the Brindabella Ranges near Canberra. And in Messiaen's Des Canyons Aux Etoiles Section IX, "Le Moquer Polyglotte" includes references to both species.

It is difficult to keep lyrebirds in aviaries, and very difficult to get them to breed in captivity. This has rarely been achieved. In captivity, where a lyrebird cannot learn from other lyrebirds, he may mimic what he does hear, such as the noise of a camera shutter and a camera motor winding on a film.

One group of lyrebirds, east of Armidale in New South Wales, has a remarkable flute-like territorial song. In the 1920s a male superb lyrebird chick was taken from the nest and raised in captivity with the domestic chickens on a farm. It could not hear other lyrebirds, and so learned to sing like the flute it heard being practiced by the farmer's son. When later this bird was released back into the wild, its "flute" calls became adopted as the territorial songs of that population. The accuracy of this story has been disputed on the grounds that the same song occurs some 60 mi (100 km) away from the release site, but it could have been culturally transmitted that far in 70 years.

Species accounts

List of Species

Albert's lyrebird
Superb lyrebird

Albert's lyrebird

Menura alberti

taxonomy

Menura (Harriwhitea) alberti Bonaparte, 1850, Turanga (now Terania) Creek, Richmond River, Australia. Monotypic.

other common names

English: Prince Albert's lyrebird, Northern lyrebird; French; Ménure d'Albert; German: Braunrücken-Leierschwanz; Spanish: Ave Lira de Alberti.

physical characteristics

34–37 in (86–94 cm); 2.0 lb (0.92 kg); female weight not recorded. Tail (longest feathers), male 20 in (51 cm), female 16 in (40 cm). The male's outer pair of tail feathers are plain and fully webbed, dark brown above and dark gray below, and are the shortest at about 15 in (38 cm); the next six pairs of "filamentary" feathers, dark brown above and light gray underneath, are about 20 in (51 cm). The central pair are about 21 in (53.5 cm), but only 0.5 in (1.3 cm) wide.

distribution

Southeastern Queensland and northeastern New South Wales: approximately Laidley to Ballina.

habitat

Subtropical rainforest, wet sclerophyll forest with rainforest understory, Antarctic beech (Nothofagus) forest.

behavior

Males defend separate individual territories in dispersed leks, using vocal and visual displays to attract females for mating. Display arenas consist of crossed thin vines and sticks lying loosely on the ground and able to move with the movement of the bird's feet. During the display, the male grasps a vine and vigorously moves it up and down during his gronking song. When the vines and sticks are dry, this makes a tapping sound in perfect time with the rhythmic notes of the song. In effect he is using "rhythm sticks"—possibly the only bird in the world to accompany its song with a musical instrument.

feeding ecology and diet

Scratches in leaf litter and surface soil for invertebrate fauna.

reproductive biology

Female alone builds nest and raises the chick. Single egg laid mostly in June.

conservation status

Not threatened. No population estimates. Probably secure as a species, but some concern because of limited distribution. Several small isolated populations at risk.

significance to humans

Some shot for food or ornamental tails early in twentieth century. Now held in high regard by the public. Significant in ecotourism.


Superb lyrebird

Menura novaehollandiae

taxonomy

Menura novaehollandiae Latham, 1802, Upper Nepean River, New South Wales. Three subspecies.

(The specific name novaehollandiae has been and remains in general use. However, its adoption was based on a mistake as to the date of publication, and on a strict interpretation of the International Code of Zoological Nomenclature, the name superba, Davies, should take priority. An application has been made to the International Commission for suppression of superba as an unused senior synonym.)

other common names

English: Superb lyrebird, Edward lyrebird, Prince Edward lyrebird, Victoria lyrebird, Queen Victoria lyrebird; French; Ménure superbe; German: Graurücken-Leierschwanz; Spanish; Ave Lira Soberbia.

The lyrebird was well-known to the Aboriginal people. Names from various language groups included: balangara, bulan-bulan, beleck-beleck, golgol, and woorayl. The double names almost certainly were derived from the loud double notes of the lyrebird's "pilick" song.

physical characteristics

30–39 in (76–100 cm); female 1.9 lb (0.88 kg), male 2.3 lb (1.06 kg). Male has highly ornamental tail, 28 in (71 cm). Outer pair of feathers elongated S-shape, decorated with semi-transparent "windows"; six pairs of filamentary feathers; central pair very narrow. Very strong legs and feet. Long claws span 6 in (15 cm).

distribution

M. n. edwardi: Hunter River north to near Stanthorpe; M. n. novaehollandiae: Hunter River to Victorian border; M. n. victoriae: Victoria, east of Melbourne, plus Snowy Mountains to Brindabella Range in New South Wales.

habitat

Wet sclerophyll forest, subtropical and temperate rainforest, Antarctic beech (Nothofagus) forest, dry sclerophyll forest, eucalyptus woodland.

behavior

Separate male and female territories. Males sing and display on arenas consisting of low earth mounds. Sedentary. Mostly solitary, occasionally two or more together.

feeding ecology and diet

Forage on the ground for invertebrates in soil and litter, scratching and digging to a depth of several inches (10 cm).

reproductive biology

Males promiscuous. Female alone builds nest, incubates the single egg, and cares for the chick, which sometimes still begs from its mother at start of next breeding season.

conservation status

All three subspecies are not threatened, though considerable reduction in habitat through European settlement. Some small isolated populations may be at risk.

significance to humans

Hunted for food and ornamental tails by early European settlers. This is the species that is now well-known and highly regarded by the public.


Resources

Books

Higgins, P. J., J. M. Peter, and W. K. Steele, eds. Tyrant-flycatchers to Chats. Vol. 5 of Handbook of Australian, New Zealand and Antarctic Birds. Melbourne: Oxford University Press, 2001.

Schodde, R., and I. J. Mason. The Directory of Australian Birds—Passerines. Collingwood, Australia: CSIRO Publishing, 1999.

Smith, L. H. The Life of the Lyrebird. Richmond, Australia: William Heinemann Australia, 1988.

Periodicals

Bock, W. J., and M. H. Clench. "Morphology of the Noisy Scrub-bird, Atrichornis clamosus, (Passeriformes: Atrichornithidae): Systematic Relationships and Summary." Records of the Australian Museum 37, nos. 3 and 4 (1985).

Curtis, H. S. "The Albert Lyrebird in Display." Emu 72 (1972): 81–84.

Robinson, F. N., and H. S. Curtis. "The Vocal Displays of the Lyrebirds (Menuridae)." Emu 96 (1996): 258–275.

Smith, L. H. "Structural Changes in the Main Rectrices of the Superb Lyrebird Menura novaehollandiae in the Development of the Filamentary Feathers." Emu 99 (1999): 46–59.

H. Sydney Curtis, BSc

Darryl N. Jones, PhD