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Comb-crested Jacana  -  Irediparra gallinacea
comb-crested jacana
Comb-crested Jacana walking over lily-leaves on a freshwater lake near Georgetown, Queensland.
map map The Comb-crested Jacana - Irediparra gallinacea - has very long toes (about 75mm long) which allow the bird to walk across lily leaves and other water plants searching for food. This ability to "walk on water" combined with a brightly coloured comb on the forehead makes the Jacana distinctive. This species is highly adapted to life alone or in pairs on tropical lagoons and feeds and nests on floating vegetation, especially lily leaves. Adult Jacanas can swim and dive (although not having webbed feet) but prefer to fly a short distance to avoid danger. Flight is ungainly and awkward; when startled they take off low, rapidly beating their wings and stretching their legs but soon alight. In an excited bird the colour of the comb may change to yellow if blood drains from the comb.

Adult birds (males 200-210 millimetres, females 240-270 millimetres) have long necks and long legs with long, slender toes; the bright red fleshy comb on the forehead extends towards the base of the bill. The crown, back of the neck, breast band, tail and flight feathers are black; back and upper wing are grey to deep olive-brown; neck and belly are white; lower neck is golden-buff. Face is white and yellow-buff with a black line from the eye to the base of the lower bill; eye is yellow, bill is orange-yellow tipped brown. Legs, feet and toes are green.

immature Jacana Immature Jacana lacking the adults red comb and with more subdued colouring.
Jacana - page 2
comb-crested jacana
Comb-crested Jacana with a foot clear of the water showing the long toes and the overall green colour of the feet and legs. The hind toe is particularly long.
Male and female are similar in colouring; females are up to half as big again as males.

Immature Jacanas have a rufous head and nape, breast white without black breast band with a barely formed comb. More developed immature birds have black and rufous breast band, head and nape.

Eats mainly aquatic plants, seeds and insects. Mostly feeding by day.

Breeding takes place from September to May with local variation. In eastern Australia between September and January and later, from January to May, in northern Australia, probably because of monsoonal rain. A mated pair vigorously defends their territory against other Jacanas. The nest is made of fine green water-plant stems laid mainly on lily leaves, usually in water more than a metre deep. Three or four eggs are laid, glossy bright tan, thickly covered with black marks and fine wavy brown lines; about 30 by 23 millimetres. Both parents incubate the eggs. Nests are easily damaged and Jacanas may move their eggs to another nest, carrying them under the chin.

Both parents look after the chicks; adults become wary when nesting and may perform a distraction display, floundering as if they have a broken wing. Jacana chicks hatch with long toes and are mobile enough to avoid predators or can tumble into the water and hide beneath floating leaves with only the tip of the bill above the surface for up to half an hour. Small chicks can be carried tucked under the parent's wings.

Lives on deeper, permanent, still, freshwater swamps, ponds and billabongs. Range extends along coastal north and eastern Australia from the Kimberley (about Broome) east and south to the Hawkesbury River. Locally abundant on rich, undamaged wetlands in remote or protected north coastal Australia but increasingly uncommon to scarce towards the southern extremity of the range where lagoons have been damaged by stock or other activity.

This species is also known as Metapidius (Irediparra) gallinacea.

The Pheasant-tailed Jacana (Hydrophasianua chirurgus) is a similar bird with a long, dark tail; non-breeding birds do not have a comb. Found mainly in Java and Timor with occasional visitors to the Kimberley and Pilbara regions of Western Australia.

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