Cockatiel

Cockatiel
Conservation status
Least Concern
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Psittaciformes
Family:	Cacatuidae
Subfamily:	Calyptorhynchinae
Genus:	Nymphicus Wagler, 1832
Species:	N. hollandicus
Binomial name
Nymphicus hollandicus (Kerr, 1792)
Cockatiel range (in red; all-year resident)
Synonyms
Psittacus hollandicus Kerr, 1792 Leptolophus hollandicus

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 Cacatuidae (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 favor the Australian wetlands, scrublands, and bush lands.

Description

The Cockatiel's distinctive erectile crest expresses the animal's state of being. (Some say "emotional state.") The crest is dramatically vertical when the cockatiel is startled or excited, gently oblique in its neutral or relaxed state, and flattened close to the head when the animal is angry or defensive.

The "Normal Grey," or "Wild-type" cockatiel's plumage is primarily grey with prominent white flashes on the outer edges of each wing. The face of the male is yellow or white, while the face of the female is primarily grey or light grey, and both genders feature a round orange area on both ear areas, often referred to as "cheek patches." This orange coloration is generally vibrant in adult males, and often quite muted in females. Visual sexing is often possible with this variant of the bird.

(See "Mutations" below.)

In nearly every mutation, this species is sexually-dimorphic only in adulthood while immature cockatiels of both genders display the dimorphic features typical of adult hens. Generally, hens as well as immature birds of both genders display either barred, dotted and/or striped undersides of tail feathers while cocks almost always display solid colored undersides of tail-feathers. A row of clear colored (cream, white or yellow) spots can be found on every flight primary & secondary flight feathers of hens and immatures of both genders, but are usually absent in cocks.

However 2 mutations (and their varieties), namely Whiteface Lutino (erraneously called Albino) & White Clear pieds (also known as Black Eyed-White) are solid-white in both genders and thus impossible to sex visually.

ADMpieds (commonly known as either Harlequin, Pieds &/or Recessive pieds) are typically impossible to sex visually. The only pied mutation in which you can visually sex a bird is in the pearl pied coloration, which is just like the regular pearl: males lose most or all of the pearls, where the females retain them.

There is debate even amongst ornithologists of expertise as to whether or not visual sexing is reliable regardless of animal gender.

Lifespan

The Cockatiel's lifespan in captivity is generally given as 15-20 years, though it is sometimes given as short as 10-15 years, and there are reports of Cockatiels living as long as 30 years, the oldest confirmed specimen reported being 35 years old when it died. Diet and exercise, much like in humans, are often major determining factors in cockatiel lifespan. Again, breeders are divided as to the best diet.

Taxonomy and systematics

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. Travelers thought they were so beautiful that they named them after mythical nymphs. (Nymphicus literally means "little nymph.") The species name refers to New Holland, an old name for Australia. Its biological relationship had long been disputed; it is placed into a monotypic subfamily Nymphicinae but had sometimes in the past been included among the Platycercinae, the broad-tailed Parakeets.

The Cockatiel Parakeet (nicknamed Cockatiel) is now biologically classified as a genuine member of Cacatuidae on account of sharing all of the Cockatoo family's biological features. Namely ; the erectile crest, a gallbladder, powder down, suppressed cloudy-layer (enabling Lories, Lirkeets (long-tailed Lories), Parakeets & typical Parrot species display of structural colours such as aquas, blues, greens, purples & turquoises), and facial feathers covering the sides of the beak, all of which are rarely found outside the Cacatuidae family.

In contrast to most Cockatoos, the Cockatiel has long tail feathers (hence the descriptive Parakeet second part of its common name), roughly making up half of its total length. At 300 mm to 330 mm (12 to 13 ins), the Cockatiel is the smallest & only Parakeet (long-tailed) type of Cockatoo species. The latter ranging between 300 mm to 600 mm (12 to 24 ins) in length.

Mitochondrial 12S rRNA sequence data places it amongst the Calyptorhynchinae (dark cockatoos) subfamily. The unique, Parakeet morphological feature is a consequence of the decrease in size and accompanying change of ecological niche.

Sequence analysis of intron 7 of the nuclear ?-fibrinogen gene, on the other hand, indicates that it may yet be distinct enough as to warrant recognition of the Nymphicinae rather than inclusion of the genus in the Calyptorhynchinae.

Cockatiels as pets

Cockatiels are generally regarded as good pets having a "sweet" demeanor, though this is by no means a guarantee. Like most other pets, the manner in which the animal is raised, handled, and kept has a profound effect on the temperament of the animal. Some birds are quite gregarious and sociable while others can be shy, retreating to the back of the cage when an unfamiliar figure appears.

Generally, well-socialized birds are gentle and friendly. Some cockatiels enjoy physical contact, lending themselves well to domestication. Many cockatiel owners develop regular bonding rituals with their animals, engaging in preening, scratching, and even petting.

Some birds will emit a distinctive "hiss" when irritated, retreating rapidly or defending with pecking bites, which can be relatively strong for their size.

Cockatiels do have a reputation for being quite noisy and demanding of the attention of their owners on a regular basis. Their vocalizations range from ginger cheeps to piercing cries.

They can be made more secure (in the mood for singing/mimicry, playing, etc) when they have a consistent few hours of quality time per day with a person or in a person's company and a good night's sleep. Twelve hours of sleep at least is required for a happy pet, sleep taken away can cause sickness and grumpy pets. Cockatiels living in a household with late sleepers should be taken to a quiet spare room where sun doesn't shine into in the morning or if you live in a small house or unit putting your pet in the bathroom is a good idea as long as you shut the toilet lid. 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. Budgerigars and other smaller birds may choose to pick at cockatiels' feet causing lost toes. 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.

Cockatiels don't necessarily make good pets for young children because they startle easily with loud or unexpected sounds and can bite out of fear of sudden hand movements near and above their heads. The shoulders of children are small and unstable perches compared with those of adults, and forcing the bird to use an uncomfortable place to stand may lead to the bird disliking the child. Once bonded with their owners, they will often cuddle and play, pushing their head against hands or faces, and may nibble 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 objects (like cardboard, books, magazines, wicker baskets, etc) left unattended. Some cockatiels enjoy looking at themselves in a mirror and will engage in the activity for hours.

Vocalization

Although cockatiels are part of the parrot order, they are better at imitating whistles than speech. Some do learn to repeat phrases, and males are generally better at mimicry than females Cockatiel speech often comes out as a "whistle" when they do annunciate, the voice being soft in volume and difficult to make out. Cockatiels can mimic many sounds, such as 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.

Although some say that female cockatiels cannot speak, this in not an absolute. Males have been known to mimic noises, words and sometimes other animals. Females generally don't imitate speech, but tend to mimic sounds such as telephones, washing machines, toilet flushes, etc. Cockatiels that do imitate speech will usually mimic frequently heard phrases, particularly of the individual to which the bird feels closest.

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.

Aviculture

Cockatiel specimen combining the Opaline (cka Pearled) & ADMpied (cka recessive pied) mutations

The Cockatiel, along with the Budgerigar, is among the most popular pet bird species. Today all Cockatiels available in the pet trade are captive-bred, as Australia no longer permits the export of native wildlife, whether endangered or not.

About fifteen primary mutations have been established in the species and enable the production of many different combinations. Some such mutations include:

• ADMpied (aka Recessivepied aka Harlequin)
• Ashenfallow (eka 'Recessivesilver')
• Bronzefallow
• Cinnamon
• Dilute (eka 'Pastelsilver')
• Dominantsilver (aka 'Ashendilute')
• Edged_dilute (eka 'Spangledsilver')
• Faded
• Ino
• NSLino
• Opaline (cka Pearled)
• 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. a.k.a. stands for Also Known As; c.k.a. stands for Commonly Known As ; e.k.a. stands for Erroneously Known As ; i.k.a. stands for Incorrectly Known As.

Colour Mutations

Color mutations are a natural phenomenon equally occurring in captivity and in the wild.

The "Normal Grey" or "Wild-type" cockatiel's plumage is primarily grey with prominent white flashes on the outer edges of each wing. The face of the male is yellow or white, while the face of the female is primarily grey or light grey, and both genders feature a round orange area on both ear areas, often referred to as "cheek patches." This orange coloration is generally vibrant in adult males, and often quite muted in females. Visual sexing is often possible with this variant of the bird.

"Whiteface" cockatiels have their yellow pigments deactivated by an autosomal recessive gene, resulting in a cock with a truly white face and a hen with a more typical mottled grey face.

The "Lutino" sex-linked recessive mutation is a perfect example of a type of cockatiel that often cannot be visually sexed. Lutinos lack eumelanin pigment (enabling black, brown, grey colours and tones) and are consequently yellow to yellowish-white 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 white coloured undersides of tail-feathers.

Unfortunately, Cockatiel Parakeets of all Ino varieties (Albino, Palefaced Ino aka Creamino, Lutino, Opaline-Lutino aka Pearlino...) are usually affected with a transmittable genetic flaw monstrously enlarging the bald-spot below the crest, due to intense overbreeding and a general lack of breeders to breed it out.

A pet Lutino Cockatiel. Note the lack of dark pigment, including in the beak, eyes, feathering, feet/skin & toenails.

"Pied" cockatiel plumage patterns vary significantly from animal to animal, giving rise to cockatiel breeders & hobbyists' "heavy pied" and "light pied" loose distinctions. Unfortunately, the degree in piedness remains virtually unpredictable genetically. However, breeding heavily pied specimens together generally produces a higher percentage of heavily pied offsprings than breeding lesser pied specimens together.

It is important to know that, throughout Parrot species ; the ADMpied (AntiDiMorphic Pied) gene negates the male's ability from ever displaying his species' sexual-dimorphic features. Leading to ADMpied cockatiels being notoriously difficult to sex visually but being excellent examples for studied in genetic traits. However, in non-dimorphic species (i.e. Conures, Lovebirds, Macaws, Rosellas...) the Anti-Di-Morphic (hence ADMpied) feature cannot be expressed but piedness still is.

"Cinnamon" and "Pearled" mutations are also sex-linked recessive. In cinnamons, the melanin pigment is modified in such a way that eumelanin pigments are stopped at the brown stage of their development to becoming black. In pearls, each feathers display both clear & dark areas making for more or less boldly looking pearlings mostly on the mantles (back & wing coverts)

There are a tremendous number of colour varieties (combined mutations), including ADMpied Cinnamon, Whiteface Lutino(ika Albino, being a combination of two separate mutations), Palefaced Lutino (aka Creamino), Whitefaced Opaline (Pearl) and so on ...

The 'Whitefaced Lutino or Whitefaced Ino' is the incorrect common name of the genuine Albino mutation of the Cockatiel. The Whiteface mutation suppresses psittacin pigments (Psittaciformes' unique type of basic yellow &/or advanced orange, pink & red type of luteins aka lipochromes), while the Ino mutation suppresses eumelanin (black type of melanin).

The Albino Cockatiel is the exact genetic equivalent of any other genuine Albino mutation in other Parrot species such as the Budgerigar, the celestial aka Pacific Parrotlet, the Rose-ringed Parakeet, the Scarlet-chested Parrot and the white-eye-ringed Lovebird species. This mutation is always produced by combining the genuine Whitefaced mutation (otherwise called Blue mutation in all Lories, Lorikeets &/or typical Parrot species) and Complete Albinistic (either NSLino &/or SL Ino) mutations together.

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 Yellow-suffused (ika 'Emerald &/or Olive') mutation. Cockatiels do not actually have green pigment to their plumage, thus Yellow-suffused specimens don't either. The yellow suffusion combined with underlying black (or brown in Cinnamon specimens) pigmentation produces an illusion of greenish tones giving rise to the genetically incorrect names of 'Emerald &/or Olive' for this trait.

Many mutations retain the normal features (black eyes, grey beak, grey feet/skin & black toe nails) of Wild-type (Grey) Cockatiel Parakeets. However ;

Fallow & Ino mutations have pink to red eyes, pink feet, clear (pink) toe nails & pinkish-white beaks.

Good Cinnamon specimens look just like the normal grey, with the exception of being quite a bit more brown.

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.

Breeding

A cockatiel egg with centimetre scale

Cockatiels are a popular choice for amateur parrot breeders along with budgerigars. This is due to both the ease of getting the birds to breed (they seem to have no inhibitions, with both genders engaging in self-stimulation) and the fairly low cost of the equipment needed. Generally a clutch consists of 4-5 eggs, each approximately the size of one's thumbnail. Eggs are laid once every two days and incubate for about 19 days. Hatchlings 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 1 year and 9 months in males and/or 15 months in females.

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, much as those of the chicken species used for food production. In this event, the owner should 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 by covering it earlier in the evening and leaving the cage 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.

It has been suggested by some breeders that petting the back of the female cockatiel may inadvertently sexually stimulate the hen, promoting egg-laying, and that owners seeking to avoid egg-laying should avoid this particular form of bonding.

The Cockatiel has recently been shown to be capable of hybridizing with the Galah, producing offspring described by the media as 'Galatiels'.

Gallery

• 
  A Wildtype (natural Grey coloured) Cockatiel showing excitement or interest by its erected crest.
• 15 year old female hand-reared & socialized Cockatiel of typical colouring.
  15 year old female hand-reared & socialized Cockatiel of typical colouring.
• A young pet ADMpied Cockatiel.
  A young pet ADMpied Cockatiel.
• 
  A pair of bonded Cockatiels mating.
• 
  Near-completely clear (notice the small grey coloured feathers near the edge of its wing) ADMpied Cockatiel.
• 3 week old Albino Cockatiel chick.
  3 week old Albino Cockatiel chick.
• 
  A White-faced Cockatiel sleeping.
• Cockatiel plumage glowing under a blacklight.
  Cockatiel plumage glowing under a blacklight.

See also

• Whiteface Lutino Cockatiel
• Parrot harness

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

• Template:IUCN2006 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

• Martin, Terry (2002). A Guide To Colour Mutations and Genetics in Parrots. ABK Publications. ISBN 0957702469.
• Hayward, Jim (1992). The Manual of Colour Breeding. The Aviculturist Publications. ISBN 0951909800.

External links

• Cockatiels at Curlie
• Genetics and heredity of the Whiteface Lutino cockatiel
• Martin Rasek's Cockatiel Parakeet's Genetic calculator
• Inte ONSMAN's MUTAVI Research and Advice Group
• Clive Hesford's Cockatiel Parakeet section from The Genetics of Colour in the Budgerigar and other Parrots website