COCKATIEL

The 'Cockatiel' (''Nymphicus hollandicus''), also known as the 'Quarrion' and the 'Weero', is a diminutive Cockatoo endemic to Australia and prized as a household pet.
The only members of their genus, Cockatiels are now biologically classified as the smallest of the Cockatoo Family. These sweet-tempered birds are valued throughout the world as pets due to their gentle and sociable nature. These birds are found across the outback regions of inland Australia, and favour the Australian wetlands, scrublands, and bush lands.

Contents

Description

Taxonomy

Cockatiels as pets

Distribution and habitat

Aviculture

Colour Mutations

Breeding

Gallery

See also

Footnotes

References

External links

Description

The Cockatiel's distinctive pointed crest is held erect when startled,excited, or when sleeping while a crest slightly tilted indicates a relaxed state of mind. The Wildtype (natural coloured) Cockatiel's plumage is generally mid-grey, lighter underneath, with an almost perfectly round orange patch on both ear coverts (usually referred to as the "cheek patches") and a prominent white flash on the outer edge of each wing. Adult male cockatiels also have a brilliant yellow (or sometimes almost white) face.
This species is sexually-dimorphic only in adulthood while immature cockatiels of both genders display the dimorphic features typical of adult hens. A row of clear coloured (cream, white or yellow) spots can be found underneath the wings of hens as well as immatures of both genders, but is always absent in cocks. Hens as well as immature birds of both genders display either barred, dotted and/or striped (i.e. cream & beige, white and grey, yellow and brown) underside of tail feathers while cocks always display solid coloured (i.e. beige, black, brown, grey, silver or white) underside of tail-feathers.
Contrary to the common belief, adult Cockatiels can be visually-sexed by their crest, head and/or ear coverts colourations only in Wildtype (natural coloured) specimens. Where Wildtype cocks display near entirely yellow crests, faces and orange cheek patches, Wildtype hens and immatures of both genders display basically grey crests and faces with minor yellow streaks as well as greyish-orange cheek patches. The latter dimorphic features (basically clear faces in cocks versus basically dirty faces in hens and immatures of both genders) are retained in most primary mutations except in every ADMpied & Ino varieties.
The Lutino mutation, for example, which completely lacks eumelanin pigment (enabling black, brown, grey colours and tones), being basically yellowish-white with orange cheek-patches in most specimens although some rare Lutino lineages are near-entirely yellow with orange cheek patches. Adult female Lutinos as well as immature Lutinos of both genders display yellow bars, dots and/or stripes on the underside of their tail feathers while mature males always display solid coloured underside of tail-feathers which are pure white in adult male specimens.
Only in the genuine Albino (often called Whitefaced Lutino or Whitefaced Ino) and the ADMpied (simply known as Pied and/or Recessivepied) mutation and all of it's numerous varieties (i.e. Cinnamon Pied, Opaline Pied aka Pearl Pied, Whitefaced Pied) is there no visual-sexing possible. This is because throughout species, genuine Albino specimens are always entirely pure-white and because the ADMpied (AntiDiMorphic Pied) gene always negates the male's ability from ever displaying his species' sexual-dimorphic features.
The Cockatiel's lifespan in captivity is generally given as 15-20 years,^[1] though it is sometimes given as short as 12-15 years^[2] and there are reports of Cockatiels living as long as 30 years, the oldest confirmed specimen reported being 35 years old when it died.^[3]

Taxonomy

Placed in its own Genus, the Cockatiel's scientific name ''Nymphicus hollandicus'' reflects the experience of one of the earliest groups of Europeans to see Cockatiels in their native habitat. Travellers thought they were so beautiful that they named them after the mythical creatures, the nymphs (''Nymphicus'' means literally "little nymph"). The species name refers to New Holland, an old name for Australia. It's biological relationship had long been disputed; it was usually placed into a monotypic subfamily 'Nymphicinae' or even allied with the Platycercinae aka broad-tailed Parakeets.
The Cockatiel is now biologically classified as a genuine member of the Cacatuidae on account of sharing everyone of the Cockatoo Family's biological features, including the erectable crest, a gallbladder, powder down patches, suppressed cloudy-layer (which enables Lories, Lorikeets & typical Parrot species display of structural colours such as aquas, blues, greens, purples & turquoises) and facial feathers covering the sides of the beak, which are rarely - if ever - found outside the Cacatuidae family. In contrast to most Cockatoos, the Cockatiel has long tail feathers (hence the descriptive Parakeet 2nd part of it's common name), roughly making up half of its total length. At 300 mm to 330 mm, the Cockatiel is the smallest & only Parakeet (long-tailed) type of all Cockatoo species which ranges between 500 mm to 600 mm in length.
Mitochondrial 12S rRNA sequence data^[4] has finally resolved the question of its affinities by placing it amongst the ''Calyptorhynchinae''(dark Cockatoo) Subfamily. The unique, Parakeet morphological feature is a consequence of the decrease in size and accompanying change of ecological niche. Despite the latter unique adaptation, the dark Plumage, the dimorphic features and the fact that a hen Cockatiel has very recently been accidentally Hybridized with a cock Eolophus roseicapillus (Galah aka rose-breasted Cockatoo) producing one very healthy (although most probably sterile) & well offspring (see direct-link below for full story, pictures & video clip) are all clear morphological indications of it's genuine belonging among ''Calyptorhynchinae'' (dark Cockatoo) Subfamily.
Sequence analysis of intron 7 of the nuclear ''β''-fibrinogen Gene, on the other hand, indicates that it may be as distinct yet as to warrant recognition of the Nymphicinae rather than inclusion of the genus in the Calyptorhynchinae.^[5]

Cockatiels as pets

Some cockatiels can be very shy; going to the back of their cages when a stranger comes in. They can hiss and try to bite a stranger who tries to get too close to them. Cockatiels can make good pets because of their gentle nature and because they require only minimal work. However they can also be noisy and demanding for attention if they are not trained or if they are ignored too much, left in a room alone while there are many noises in other parts of the house. They can be more secure/happy (in the mood for singing/mimicry, TLC and playing) when they have a consistent few hours of quality time per day with a person or in a person's company. Cockatiels don't make good pets for young children because they startle easily with very loud and especially unexpected sounds, and often bite out of fear of sudden hand movements near and above their heads. Once bonded with their owners, they will cuddle and play, often pushing their head against hands or nibbling at fingers for attention to get a scratch on the head and back of the neck. Cockatiels, like almost all other parrots, love to chew paper and can destroy many objects (like cardboard, books, magazines, wicker baskets, etc.). Some cockatiels also love to look at themselves in a mirror and will spend hours doing it.

Distribution and habitat

Cockatiel are native only to Australia where they are found largely in arid or semi-arid country, but always near water. Sometimes hundreds will flock around a single such body of water. To farmers' dismay, they often eat cultivated crops. They are absent from the most fertile southwest and southeast corners of the country, the deepest Western Australian deserts, and Cape York Peninsula. They are the only Cockatoo species which can sometimes reproduce in the end of their first year.
Although some say that female cockatiels cannot speak, this in some way is not true. Males have been known to mimic noises, words and sometimes other animals. Females don't talk as much. They tend to mimic sounds rather than words, e.g. telephone, washing machine, toilet flush, screams, etc. If a cockatiel has a particular person that it feels most comfortable with, it may try to mimic their voice or something that they might say alot.

Aviculture

Cockatiel, along with the Budgerigar, are among the most popular pet bird species. Today all Cockatiels available in the pet-trade are/were captive-bred, as Australia no longer permits the export of native wildlife, whether endangered or not.
About 15 primary mutations have occurred and are +/- established in the species and enables the production of tens and tens of different combinations. Mutations include:

★ ADMpied (aka Recessivepied)

★ Ashenfallow (eka 'Recessivesilver')

★ Bronzefallow)

★ Cinnamon

★ Dominantsilver

★ Dilute (eka 'Pastelsilver')

★ Dominantsilver (aka 'Ashendilute')

★ Edgeddilute (eka 'Spangledsilver')

★ Faded

★ Ino

★ NSLino

★ Opaline (cka Pearl)

★ Palefaced (eka 'Pastelfaced')

★ Pallid (ika 'Platinum and/or SL Platinum')

★ Whitefaced

★ Dominant and SL (Sex-Linked) Yellowcheeked

★ Yellow-suffused (eka 'Emerald and/or Olive')
N.B. aka stands for Also Known As ; cka stands for Commonly Known As ; eka stands for Erraneously Known As & ika stands for Incorrectly Known As.
Cockatiels can form strong bonds with their owners. Otherwise quiet birds will frequently make contact calls with their owners, calls that sometimes can be quite loud if the person is out of sight. The cockatiel can grow so attached to its owner that it may try to 'protect' the owner from anyone that tries to come near it by biting or hissingCockatiels must be acquainted with the entire family, in order to assure even temperament toward all. A scared 'tiel will choose flight over fight most of the time, thus creating a chance for injury (i.e. flying into a glass door). Their popularity as pets is in part because of their calm and timid temperament, to the point that they can even be bullied by smaller but more confident birds such as Budgerigars. Great care and supervision should be provided when mixing cockatiels with other birds. It is not uncommon at all for a larger or smaller bird to maim the cockatiel, creating life-long disabilities and potentially life threatening injuries. However, some cockatiels will defend themselves.
Although cockatiels are part of the parrot order, they are better at imitating whistles than speech. Some do learn to repeat phrases, and the males are generally better at mimicry than the femalesCockatiel speech, often comes out as a "whistle", when they do annunciate, the voice is very soft and hard to make out. Cockatiels can mimic many sounds, for example the bleep of a car alarm, a ringing telephone, the sound of a zipper, the beeping of cell phones or microwaves, or the calls of other bird species such as blue jays or chickadees and loud weather like thunder. They can also mimic other pets such as dogs, occasionally barking back.

Colour Mutations

Wildtype (natural Grey coloured) cockatiels are basically medium grey coloured and display white flashes on the edge of their wing coverts. Colour mutations are desirable for show and some owners, however a number of these are sex-linked and/or recessive. For example, the Lutino mutation is such that the individual does not produce eumelanin, resulting in a phenotype of no grey coloration in every body structures & tissues. The genotype is Xino Y (female cockatiel with copy of the Ino mutation on her single complete aka X chromosome) or Xino Xino (male cockatiel with copies of the Ino mutation on both his complete aka X chromosomes). Male cockatiels with a genotype of Xino X carry the Ino mutation, but do not express it and thus do not appear Lutino and are then described as Split/ Ino.^[6] (Note that in birds, XY denotes female, while XX is male; some ornithologists use different letters such as ZW for female and ZZ for male.)Unfortunatly, Cockatiel Parakeets of all Ino varieties (Albino, Palefaced Ino aka Creamino, Lutino, Opaline-Lutino aka Pearlino...) are usually affected with a transmittable genetic flaw where the bald spot under their crest is monstruously enlarged.

Mutations can appear both individually or in a wide variety of combinations such as Opaline Lutino aka Pearlino, Whiteface Pied, Opaline-Cinnamon aka Cinnamon-Pearl and Albino cka whiteface lutino. Still fairly hard to find is the rather new Suffused-yellow cka 'Emerald &/or Olive' mutation. Suffused-yellow Cockatiel does not actually have green pigment to its plumage, but rather an overlapping pattern of yellow and grey that create the illusion of a greenish cast.
Many mutations retain the black eyes, beak, nails and grey feet of the normal grey Cockatiel Parakeets, however Fallow & Ino mutations have pink to red eyes, pink feets, clear (pink) toe nails & pinkish-white beaks. Genuine Cinnamon specimens display plum-red eyes upon hatching but these rapidly darken & stabilize to a near-natural (brown) colour around 10 to 15 days of age and thus way before they leave the nest. While most mutations persist into adulthood for all Cockatiel Parakeets, certain mutations like Opaline (aka Pearl) are molted out in the males upon going through their adult molt although retained in the adult females. Sex-linked mutations such as Cinnamon, Ino, Opaline, Pallid (eka Platinum) &/or SL-Yellowfaced have a higher ratio of female offspring to male due to the mode of inheritance from parents to offspring.^{6[7] [8] [9]} As Lutino and Albino Cockatiel Parakeets lack the pigment melanin, these birds will have red eyes.

Breeding

Cockatiels are a popular choice for amateur parrot breeding along with budgerigars. This is due to both the ease of getting the birds to breed (they have no inhibitions whatsoever) and the fairly low cost of the equipment needed. Generally a clutch consists of 5-7 eggs, each approximately the size of one's thumbnail. Eggs are laid once every two days and incubate for about 19 days. Hatchings are weaned in 4 weeks, and can fly around 2 months. Puberty (adolescence) is reached around 9 months of age while adulthood is reached around 12 months in males and/or 15 months in females. ^[10]
Male cockatiels are very protective and nurturing of their offspring and are known to be very capable of raising their newborns if the mother is unable to.
Some female cockatiels also lay eggs without fertilization (as do chickens; both infertile). In this case, the owner should just leave the eggs alone until the bird stops sitting on them, after which the eggs can be removed. To prevent laying, one can keep the cockatiel in more darkness per day, such as by covering it up for the night earlier and leaving it covered longer in the morning. Like all parrots, cockatiels of either gender can grow to see their owner or a toy as a mate, engage in courtship and mating behavior including territoriality, and females may lay infertile eggs.^[11]
It is almost imposible to tell a female apart from a male. There are many different theorys about how to tell, however they are still yet to be prooved. Unlike budgies, cockatiels do not have a different beak colour depending on the gender. Some ways that people have suggested at pet shops and vets are: Feel down the front of your cockatiels belly, if the brest bone goes straight down, it is a male. If the bone has an upsidedown v shape it is a female (this is the are that the female will store its egg in). The best way, is to wait until your cockatiel is about 1 year and 6 months, it should ten start to lay eggs.
The Cockatiel has recently been shown to be capable of hybridizing with the Galah, producing offspring described by the media as 'Galatiels'.^[12]

Gallery

See also

★ Whiteface Lutino Cockatiel

★ Parrot harness

Footnotes

1. cockatielcottage.net
2. letstalkbirds.com
3. Petlovers.com
4. Brown, D.M. & Toft, C.A. (1999): Molecular systematics and biogeography of the cockatoos (Psittaciformes: Cacatuidae). Auk 116(1): 141-157.
5. Astuti, Dwi (2004): A phylogeny of Cockatoos (Aves: Psittaciformes) inferred from DNA sequences of the seventh intron of Nuclear β-fibrinogen gene. Doctoral work, Graduate School of Environmental Earth Science, Hokkaido University, Japan.
6. Kiesewetter, Cynthia. Cockatiel Genetics for the Beginning Breeder: The Albino Cockatiel. http://www.upatsix.com/fyi/tiel_genetics.htm Viewed Feb 5 2007.
7. Cockatiel Genetics, Feather Affair, viewed 20 May 2007
8. Genetic Terms, Cynthia Kiesewetter, North American Cockatiel Society, 2000
9. Albino (cka Whitefaced Ino) and Other Whiteface Ino Crosses, Linda S. Rubin, National Cockatiel Society, 2003
10. Cockatiels.org
11. How Not to be a Tease: Discouraging mating behaviors in parrots, 17 February 2006.
12. http://www.talkingbirds.com.au/worldfirst-galah.php

References

★ 'Astuti', Dwi (2004?): A phylogeny of cockatoos (Aves: Psittaciformes) inferred from DNA sequences of the seventh intron of nuclear ''β''-fibrinogen gene. Doctoral work, Graduate School of Environmental Earth Science, Hokkaido University, Japan. PDF fulltext

★ Database entry includes justification for why this species is of least concern

★ 'Brown', D.M. & 'Toft', C.A. (1999): Molecular systematics and biogeography of the cockatoos (Psittaciformes: Cacatuidae). ''Auk'' '116'(1): 141-157.

★ 'Flegg', Jim (2002): ''Photographic Field Guide: Birds of Australia''. Reed New Holland, Sydney & London. ISBN 1-876334-78-9

External links