The Northern Rosella (Platycercus venustus), also known as Brown's Parakeet or Smutty Rosella, is found in Australia's Top End. It is unusually coloured for a rosella, with a dark crown and white cheeks similar to its relatives the Pale-headed Rosella and the Eastern Rosella.

At 28 cm long it is smaller than all bar the Western Rosella. The forehead, crown and nape are black in colour with white-on-blue cheek-patches. The back and wing feathers are blackish with yellow borders, while the feathers of the belly, chest and rump are pale yellow with black borders giving rise to a scalloped appearance. The long tail is bluish green. The bill is pale grey and the iris dark. Immature plumage is similar to adult but duller.

The Northern Rosella is found from the Gulf of Carpentaria, through Arnhem Land to the Kimberleys in open savannah country.

It is not a gregarious bird, found solitarily or in pairs. Nesting occurs in tree hollows in winter, with two to four eggs laid.

The Northern Rosella was first described by German naturalist Heinrich Kuhl. The specific epithet is derived from the Latin venustus "charming, lovely or graceful". A subspecies, var. hilli, was described by Mathews in 1910, however is not felt to be valid.

In captivity, they are said to continue with their early mating habit, which is not a problem in Australia but more so in other countries.

The Eastern Rosella (Platycercus eximius) is a rosella native to southeast Australia and Tasmania. It has been introduced to New Zealand where feral populations are found in the North Island (notably in the northern half of the island and in the Hutt Valley) and in the hills around Dunedin in the South Island

Description

The Eastern Rosella is 30 cm (12 in) long. It has a red head and white cheeks. The beak is white and the irises are brown. The upper breast is red and the lower breast is yellow fading to pale green over the abdomen. The feathers of the back and shoulders are black, and have yellowish or greenish margins giving rise to a scalloped appearance that varies slightly between the subspecies and the sexes. The wings and lateral tail feathers are bluish while the tail is dark green. The legs are grey. The female is similar to the male though duller in colouration and have an underwing stripe, which is not present in the adult male. Juveniles are duller than females and have an underwing stripe.

Distribution and habitat

The Eastern Rosella is found in lightly wooded country. It eats grass seeds and fruits. Breeding occurs in spring and early summer and up to seven white eggs are laid in tree hollows.

Breeding

The breeding season is August to January, with one brood. The nesting site is usually a hollow over 1 m (3 ft) deep in a tree trunk anywhere up to 30 m (100 ft) above the ground. A clutch of generally five or six (although up to nine have been recorded) round, white and slightly shiny eggs, measuring 26 x 22 mm, is laid.

As pets

The Eastern Rosella is sometimes kept as a pet. These birds are desired for their beautifully coloured plumage. They are intelligent creatures, which can be trained to whistle a wide repertoire of tunes and may even learn to speak a few words or phrases. Rosellas can make good companion parrots; however, they require a great deal of attention and many toys to satisfy their need for social interaction and mental stimulation. These birds do not always adapt to life as a family pet and even hand-raised birds may never become fully domesticated. Generally, this species does not tolerate “petting” or “cuddling” and is apt to bite in response to this type of handling. Many people believe that Rosellas are best housed in large aviaries that enable them to fly freely with minimal human socialization. Despite these difficulties, many people enjoy the Eastern Rosella as a beautiful pet with a strong, feisty personality.

The Pale-headed Rosella (Platycercus adscitus), is a broad-tailed parrot of the genus Platycercus native to northeastern Australia. It is a moderate-size parrot with a pale yellow head, predominantly white cheeks, scalloped black and gold back and pale blue underparts. Two subspecies are recognised, although some authorities consider it to be conspecific with the Eastern Rosella of southeastern Australia.

Found in open woodland, it feeds on seeds and fruit. As with other rosellas, the Pale-headed Rosella nests in hollows of large trees. It readily adapts to aviculture and is sold as a cagebird.

Description

The Pale-headed Rosella is 33 cm (13 in) long, which includes the 15 cm length of its tail. Its underparts are pale blue, and upper breast and head are pale cream-yellow, the tail which is blue-black and green and the vent which is blood red. The feathers of the nape, scapulars and back are black edged with bright yellow, giving rise to a scalloped appearance. In these margins of the northern race, the yellow is paler with a pale blue tinge. The cheeks are wholly white in the southern subspecies, and partly flushed with blue in the lowerparts in the northern subspecies. The bill is pale blue-white and the legs dark grey. The eyes are yellow-brown. The sexes are similar in appearance, although the female is slightly smaller and duller.

Distribution and habitat

The nominate subspecies adscitus is found from the Cape York Peninsula south through to Cardwell in central-northern Queensland. There is a broad range of intermediate forms, while the southern subspecies palliceps extends from Townsville and points inland south into northeastern New South Wales to the vicinity of the Clarence River. It is common throughout its range. Its preferred habitat is open forest, but has adapted well to human modification of the rural landscape and may even become a pest to orchards and cereal crops. Watering troughs help the species in the dryer western limits of its range

It was also introduced to Hawaii in 1877, but had died out there by the late 1920s.

Feeding

It eats grass and tree seeds and fruits, including River Red-gum (Eucalyptus camaldulensis), River Sheoak (Casuarina cunninghamiana), Snow-in-summer (Melaleuca linariifolia) and other melaleucas, and Rough Cockleburr (Xanthium strumarium). Birds are partial to the introduced Scotch Thistle (Onopordum acanthium).

Breeding

The breeding season varies according to region, with southern birds nesting from September to December and northern ones later from February to June. One brood is laid. The nesting site is usually a hollow over 1 m (3 ft) deep in a tree trunk anywhere up to 30 m (100 ft) above the ground. A clutch of five or six (although up to nine have been recorded) round, white and slightly shiny eggs, measuring 26 x 22 mm, is laid.

Aviculture

The species is relatively hardy and easy to keep in cultivation. It can be aggressive and so is recommended to be segregated from other birds in captivity.

The Green Rosella or Tasmanian Rosella (Platycercus caledonicus) is endemic to Tasmania. At 36 cm (14 in), it is the largest of the Rosellas. The male and female are similar in plumage, being predominantly green and yellow in colour with blue cheeks. Its diet is composed of seeds, fruit, berries and flowers, as well as insects and insect larvae.

Description

Measuring 36 cm (14 in) in length, the adult Green Rosella has a yellow head and underparts with blue cheeks and red frontal band above the bill. The feathers of the back and wings are black with green margins, the rump olive and the long tail green with blue borders. The lateral wing feathers are pale blue. The iris is brown, while the legs are grey and the bill pale tan-grey. The female is similarly coloured and usually a little smaller. Juvenile birds have dull yellow-green head and underparts and dull green upperparts, and a wing stripe.

Distribution and habitat

The Green Rosella is found across Tasmania and Bass Strait islands, and occurs in most habitats with some form of tree cover.

Feeding

The Green Rosella is predominantly herbivorous, consuming seeds, berries, nuts and fruit, as well as flowers, but may also eat insect larvae and insects such as psyllids. They have also partaken of the berries of the common hawthorn (Crataegus monogyna), as well as Coprosma and Cyathodes, and even leaf buds of the Common Osier (Salix viminalis). The seeds of the Silver Wattle (Acacia dealbata) are also eaten.

Breeding

The breeding season is October to January, with one brood. The nesting site is usually a hollow over 1 m (3 ft) deep in a tree trunk anywhere up to 30 m (100 ft) above the ground. A clutch of four or five white and slightly shiny eggs, measuring 30 x 24 mm, is laid. The nestlings leave the nest around five weeks after hatching and remain with their parents for another month.

The Crimson Rosella (Platycercus elegans) is a parrot native to eastern and south eastern Australia which has been introduced to New Zealand and Norfolk Island. It is commonly found in, but not restricted to, mountain forests and gardens. The species as it now stands has subsumed two former separate species, The Yellow Rosella and the Adelaide Rosella. Molecular studies show one of the three red-coloured races, var. nigrescens is genetically more distinct.

Description

Platycercus elegans is a medium-sized Australian parrot at 36 cm (14 in) long, much of which is tail. There are five subspecies, three of which are actually crimson. The red is replaced by yellow in the case of var. flaveolus and a mixture of red, orange and yellow in the Adelaide Rosella.

Adults and juveniles generally show strikingly different colouration in south-eastern populations, with predominantly greenish-olive body plumage on the juvenile, most persistent on the nape and breast. Juveniles are said to 'ripen' as they get older and turn from green to red. All races have blue cheeks and black-scalloped blue-marginned wings and predominantly blue tail with predominantly red coloration. The Crimson Rosella’s blue tail feathers are one of the favourite decorations of the Satin Bowerbird. The bill is pale grey and the iris dark brown.
There is very little sexual dimorphism in Crimson Rosellas. The most noticeable difference between genders is that males are up to 15% larger, and have a relatively larger and wider beak.

Crimson Rosella

P. elegans elegans, the nominate race of Victoria and eastern New South Wales. P. elegans nigrescens, occurring on Queensland's northeastern coast, and P. elegans melanoptera on Kangaroo Island. The main distinctions between these is size: nigrescens is the smallest of the three and melanoptera is the largest; both are slightly darker than the nominate race.

The juveniles of var. nigrescens lack the greenish immature plumage of the other subspecies of Crimson Rosella

Yellow Rosella

The Yellow Rosella, which lives along the Murray River, was reclassified (1968) as a subspecies, P. elegans flaveolus, of the Crimson as the two were found to interbreed where their ranges overlap. The main difference between the two is that those parts of the Crimson which are red are on the Yellow bright yellow.

Adelaide Rosella

The Adelaide Rosella of Adelaide and the surrounding area, was also thought to be a separate species, but is presently believed to be a hybrid swarm, having originated through interbreeding of the Crimson and Yellow Rosellas. Both of these still interbreed with the Adelaide Rosella where its range crosses theirs, and it exhibits variation in its plumage from dark orange-red in the south of its distribution to a pale orange-yellow in the north. Variants that are very close to the Yellow race are designated subadelaidae.

Distribution and habitat

The Crimson Rosella occurs from southeastern South Australia, through Victoria and coastal New South Wales into Southeastern Queensland. A disparate population occurs in North Queensland.

It is common in coastal and mountain forests at all altitudes. It primarily lives in forests and woodlands, preferring older and wetter forests. They can be found in tropical, subtropical, and temperate rainforests, both wet and dry sclerophyllous forests, riparian forests, and woodlands, all the way from sea-level up to the tree-line. They will also live in human-affected areas such as farmlands, pastures, fire-breaks, parks, reserves, gardens, and golf-courses. They are rarely found in treeless areas. At night, they roost on high tree branches.

Behaviour

Almost all Rosellas are sedentary, although occasional populations are considered nomadic; no Rosellas are migratory. Outside of the breeding season, Crimson Rosellas tend to congregate in pairs or small groups and feeding parties. The largest groups are usually composed of juveniles, who will gather in flocks of up to 20 individuals. When they forage, they are conspicuous and chatter noisily. Rosellas are monogamous, and during the breeding season, adult birds will not congregate in groups and will only forage with their mate.

Feeding

Crimson Rosellas forage in trees, bushes, and on the ground for the fruit, seeds, nectar, berries, and nuts of a wide variety of plants, including members of the Myrtaceae, Asteraceae, and Rosaceae families. Despite feeding on fruits and seeds, Rosellas are not useful to the plants as seed-spreaders, because they crush and destroy the seeds in the process of eating them. Their diet often puts them at odds with farmers whose fruit and grain harvests can be damaged by the birds, which has resulted in large numbers of Rosellas being shot in the past. Rosellas will also eat many insects and their larvae, including termites, aphids, beetles, weevils, caterpillars, moths, and water boatmen.

Breeding

Nesting sites are hollows greater than 1 metre (3 feet) deep in tree trunks, limbs, and stumps. These may be up to 30 metres (100 feet) above the ground. The nesting site is selected by the female. Once the site is selected, the pair will prepare it by lining it with wood debris made from the hollow itself by gnawing and shredding it with their beaks. They do not bring in material from outside the hollow. Only one pair will nest in a particular tree. A pair will guard their nest by perching near it at chattering at other Rosellas that approach. They will also guard a buffer zone of several trees radius around their nest, preventing other pairs from nesting in that area.

The breeding season of the Crimson Rosella lasts from September through to February, and varies depending on the rainfall of each year; it starts earlier and lasts longer during wet years. The laying period is on average during mid- to late October. Clutch size ranges from 3-8 eggs, which are laid asynchronously at an average interval of 2.1 days; the eggs are white and slightly shiny and measure 28 x 23 mm. The mean incubation period is 19.7 days, and ranges from 16–28 days. Only the mother incubates the eggs. The eggs hatch around mid December; on average 3.6 eggs successfully hatch. There is a bias towards female nestlings, as 41.8% of young are male. For the first six days, only the mother feeds the nestlings. After this time, both parents feed them. The young become independent in February, after which they spend a few more weeks with their parents before departing to become part of a flock of juveniles. Juveniles reach maturity (gain adult plumage) at 16 months of age.

Mutations

Next to the nominate bird which is mainly red coloured a few other colour mutations exist such as the blue, yellow, white and cinnamon mutations.

Threats

Crimson Rosellas may be eaten by cats or dogs, and have been found to make up a small part of the diet of the fox in some areas. Possums and currawongs are also believed to occasionally take eggs from the nest. Surprisingly, however, the Crimson Rosella is its own worst enemy. During the breeding season, it is common for females to fly to other nests and destroy the eggs. In fact, this is the most common cause for an egg failing to hatch. This behaviour is thought to be a function of competition for suitable nesting hollows, since a nest will be abandoned if all the eggs in it are destroyed, and a pair of Rosellas will tend to nest in the same area from year to year.

The Western Rosella Platycercus icterotis, less commonly known as the Stanley Rosella, Earl of Derby's parakeet or Yellow-cheeked parakeet, is the smallest species of rosella and is found in the South West of Australia. in Eucalypt forests and timbered areas. Just under 30cm (or one foot) long; they are red from the head to the breast with white or beige-ish yellow cheeks and blue and green patterned wings with males being slightly larger and having a more vibrant yellow cheek colouring. Their bills are a grey 'horn' colour like most Australian parrots.

Habitat, Breeding and Diet

Western Rosellas socialise in pairs but will often congregate in largish groups of twenty or so to forage when the season permits; their diet is herbivorous, consisting mostly of grass and seeds. They nest mostly in hollow tree trunks usually a meter or so deep and will favour hollows that have dust in the bottom (as may be created by insects boring out the tree or limb). The female incubates the eggs and leaves in the morning and afternoon to eat food found by the male.

Domestic Rosellas

Western Rosellas make reasonable pets however they have a habit of being aggressive if kept with other pets. They are largely sociable with humans and will whistle in return if whistled at.