Crimson Rosella
Encyclopedia
The Crimson Rosella is a parrot
Parrot
Parrots, also known as psittacines , are birds of the roughly 372 species in 86 genera that make up the order Psittaciformes, found in most tropical and subtropical regions. The order is subdivided into three families: the Psittacidae , the Cacatuidae and the Strigopidae...

 native to eastern and south eastern Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 which has been introduced to New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 and Norfolk Island
Norfolk Island
Norfolk Island is a small island in the Pacific Ocean located between Australia, New Zealand and New Caledonia. The island is part of the Commonwealth of Australia, but it enjoys a large degree of self-governance...

. It is commonly found in, but not restricted to, mountain forests and garden
Garden
A garden is a planned space, usually outdoors, set aside for the display, cultivation, and enjoyment of plants and other forms of nature. The garden can incorporate both natural and man-made materials. The most common form today is known as a residential garden, but the term garden has...

s. 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.

Taxonomy

Though described by Johann Friedrich Gmelin
Johann Friedrich Gmelin
Johann Friedrich Gmelin was a German naturalist, botanist, entomologist, herpetologist and malacologist.- Education :Johann Friedrich Gmelin was born as the eldest son of Philipp Friedrich Gmelin in 1748 in Tübingen...

 in Systema Naturae
Systema Naturae
The book was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. The first edition was published in 1735...

as Psittacus elegans in 1788, the Crimson Rosella had been described and named by John Latham
John Latham (ornithologist)
John Latham was an English physician, naturalist and author. He was born at Eltham in Kent, and was the eldest son of John Latham, a surgeon there, and his mother was a descendant of the Sothebys, in Yorkshire....

 in 1781 as the Beautiful Lory, and then Pennantian Parrot. However he didn't give it a Latin name until 1790, when he named it Psittacus pennanti. In 1854, it was placed in the genus Platycercus by Martin Lichtenstein
Martin Lichtenstein
Martin Hinrich Carl Lichtenstein was a German physician, explorer, zoologist, and herpetologist.-Biography:...

 in his Nomenclator Avium Musei Zoologici Berolinensis.

Today, the red-coloured races are generally known as the Crimson Rosella, with the alternate names Red Lowry, Pennant's Parakeet, Campbell Parakeet, (Blue) Mountain Parrot, (Blue) Mountain Lowry or just plain Lowry occasionally heard. Cayley reported that the first two alternate names were most common in the early part of the twentieth century. On Norfolk Island it is called simply Red Parrot.

The Yellow Rosella, also known by a variety of alternate common names including Murrumbidgee Lowry, Murray Rosella, Swamp Lory and Yellow-rumped Parakeet, was described as Platycercus flaveolus by John Gould
John Gould
John Gould was an English ornithologist and bird artist. The Gould League in Australia was named after him. His identification of the birds now nicknamed "Darwin's finches" played a role in the inception of Darwin's theory of evolution by natural selection...

, who gave it the last common name mentioned. It was reduced to subspecies status once hybridization was noted where ranges overlap, however some authorities maintain the hybridization is not widespread and hence preserve its specific status. This view is in the minority, however.

The name Blue-cheeked Rosella was proposed for the united species elegans, but was not generally taken up.

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
Satin Bowerbird
The Satin Bowerbird, Ptilonorhynchus violaceus is a bowerbird endemic to eastern Australia.A rare natural intergeneric hybrid between the Satin Bowerbird and the Regent Bowerbird is known as Rawnsley's Bowerbird.-Distribution:...

. The bill is pale grey and the iris dark brown.

There is very little sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...

 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
Murray River
The Murray River is Australia's longest river. At in length, the Murray rises in the Australian Alps, draining the western side of Australia's highest mountains and, for most of its length, meanders across Australia's inland plains, forming the border between New South Wales and Victoria as it...

, 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
Adelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...

 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 Tasmania, 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
Myrtaceae
The Myrtaceae or Myrtle family are a family of dicotyledon plants, placed within the order Myrtales. Myrtle, clove, guava, feijoa, allspice, and eucalyptus belong here. All species are woody, with essential oils, and flower parts in multiples of four or five...

, Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

, and Rosaceae
Rosaceae
Rosaceae are a medium-sized family of flowering plants, including about 2830 species in 95 genera. The name is derived from the type genus Rosa. Among the largest genera are Alchemilla , Sorbus , Crataegus , Cotoneaster , and Rubus...

 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 egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...

s, 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
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...

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 and 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.

Further reading

  • Photographic Field Guide Birds of Australia (second edition); ISBN 1-876334-78-9.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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