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The rainbow pitta ( Pitta iris) is a small passerine bird in the pitta family, Pitta, endemism to northern Australia, most closely related to the superb pitta of Manus Island. It has a velvet black head with chestnut stripes above the eyes, olive green upper parts, black underparts, a bright red belly and an olive green tail. An Australian endemic, it lives in the monsoon forests and in some drier eucalypt forests.
Like other pittas, the rainbow pitta is a secretive and shy bird. Its diet is mainly insects, arthropods and small vertebrates. Pairs defend territories and breed during the rainy season, as that time of year provides the most food for nestlings. The female lays three to five blotched eggs inside its large domed nest. Both parents defend the nest, incubate the eggs and feed the chicks. Although the species has a small global range, it is locally common and the International Union for Conservation of Nature (IUCN) has assessed it as being of least concern.
The species was once treated as a subspecies of the noisy pitta of eastern Australia, and was also treated as being in a species complex with that species, the elegant pitta and the black-faced pitta, although that arrangement was not universally accepted. The 2006 study of the nuclear DNA of the pittas and other Old World found that its closest relative was the superb pitta of Manus Island off the northern coast of Papua New Guinea. The same study resulted in the pitta family being split from one genus into three, this species remaining in the genus Pitta.
The species was long thought to be monotypic, but in 1999 the Western Australian population was split into the subspecies P. i. johnstoneiana by Richard Schodde and Ian J. Mason.
The plumage is essentially the same for both sexes; females may have slightly more buff-yellow in their flanks and a slightly different shade of red on the lower belly, but these differences do not make the sexes distinguishable by plumage. The subspecies P. i. johnstoneiana is very similar to the nominate race, except the chestnut eyebrow is larger, as is the wing-spot, but the bird overall is slightly smaller.
It is found most commonly in monsoon forest and in adjacent vine-scrub and gallery forest, and also occurs in eucalypt forest, bamboo forests, Melaleuca and scrub, Lophostemon forests and the edges of mangrove forests (but never in mangrove forests themselves). It is mostly found in closed forests, but is also found in more open forests. (2025). 9780195532586, Oxford University Press. ISBN 9780195532586 It has sometimes been found in plantations of introduced pines, and has even bred in that habitat. This species is one of only two pittas that have been recorded feeding on open lawns in towns.
The species is Sedentism, most pairs occupying their territories year-round. Some local movements to more marginal habitats have been recorded during the dry season. Its movements can be difficult to trace during the post-breeding season, as it is silent during the Moulting, and generally shy throughout the year. Young birds disperse from their parents' territories, seeking territories of their own. One bird ringing juvenile was discovered from its native territory.
One common display is the bowing display, where the legs are held straight and the body held vertically, with the breast almost touching the ground. This display has only been observed being performed by males. During this display the pitta makes a purring sound not heard at any other time. This display is territorial, and is performed by neighbours along territorial boundaries, one bird displaying after another. The display and purring call are adapted to be noticeable in the dim light of the forest floor yet not so conspicuous so as to attract predators. The most commonly given call "teow-whit, teow-whit" or "choowip-choowip" is probably territorial as well.
A defensive behaviour of this species is wing-flicking, where the wings are half-opened for a second every five seconds. This behaviour is paired with a "keow" call, and is made when potential predators approach closely to a nest. It will also perform a wing-spreading display when predators are close to the nest, standing vertically and suddenly flashing open its wings. This behaviour may distract the attention of predators away from the nest. When an adult itself is threatened, it may adopt a ducking posture, holding its breast down to the ground and its tail up high.
Nesting pairs engage in a simple ritual when relieving their partner during incubation. The parent arriving will sit on a branch near the nest and issue a disyllabic whistle two or three times. On hearing this the incubating bird leaves without making a sound, and the relieving parent takes their place.
The species forages individually by hopping on the forest floor, then pausing to scan; leaves and soil are scratched by the feet and leaves may be flicked away by the bill. When feeding on snails, it breaks them out of the shells using roots as an anvil. Unlike the noisy pitta, it only uses roots and branches as anvils, not stones. Larger prey like large centipedes are shaken and dropped, then the bird retreats for a few seconds before repeating the process.
Breeding territories vary in size from ; territories are larger in drier forest. Nesting sites are placed randomly through the pair's territory, although second nests in a year are placed some distance from nests used earlier that season. Bird nest are not used more than once; if the pair lay a new clutch in a season then a new nest is constructed. Unlike the noisy pitta, which mostly places its nests close to the ground, the rainbow pitta only rarely places its nest close to the ground, possibly because its habitat floods more readily. It does place its nest anywhere from ground level up to in a tree, and the same pair can show similar variation in location within a nesting season. The nest can be placed in the fork of a tree, at the top of palms, on horizontal branches, in tangles of vines or against the buttress roots of a tree.
A nest takes about a week to build, and is built by both parents. It starts as a platform of twigs, over which is built a dome. The enclosed nest is then lined with bark and leaves before a final lining of finer fibres, fern fronds and rootlets. One unusual feature of rainbow pitta nests, shared only with the noisy pitta in this family, is the addition of wallaby dung pellets to the entrance of the nest. In a study of 64 nests in the Northern Territory, 34% were decorated in this way. The function of the dung is uncertain; it has been suggested that the scent disguises the smell of eggs, nestlings or incubating adults from nest predators, but researchers found that decorated nests were preyed upon as frequently as clean nests. Entrances may also be decorated with other objects such as dingo hair or feathers; the function of this is also unknown but may be to communicate with others of the same species. The nests of pittas may be domed to protect them from nest predators, but evidence of this is inconclusive. Nests are preyed upon by rodents and snakes, and nests are raided more often in monsoon forests than in eucalypt forests. Nesting failure is high for this species; 12% of nests are preyed upon in eucalypt forests and 60% of nests in monsoon forests.
An average clutch of rainbow pitta eggs contains four eggs, but some have three or five. The eggs are rounded and white with sepia spots and blotches and underlying grey markings. They measure on average. Both parents incubate the eggs for 14 days. Incubation stints last for an average of 87 minutes and the pair incubate their eggs for 90% of the daylight hours. The chicks are born naked, with black skin and yellow claws. Their eyes open after four days, and the down, when it comes, is grey. Both parents feed the chicks, with an average time between feeds of just 7.5 minutes. Earthworms are broken up before being fed to smaller nestlings. Chicks fledge after 14 days, before they are fully grown. They continue to be fed for between 15 and 20 days after leaving the nest, after which they are independent of their parents, and may even be driven out of the territory by their parents. Having fledged one brood, some rainbow pittas may build a new nest and lay a second brood; in one study, two out of four closely studied pairs relaid. Pairs may even build the next nest while still feeding the previous brood.
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