View source for Cockatiel

{{Short description|Species of bird}}
{{Use Australian English|date=April 2020}}
{{Speciesbox
| name = Cockatiel
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 12 November 2021">{{cite iucn |author=BirdLife International |date=2018 |title=''Nymphicus hollandicus'' |volume=2018 |article-number=e.T22684828A132056250 |doi=10.2305/IUCN.UK.2018-2.RLTS.T22684828A132056250.en |access-date=12 November 2021}}</ref>
| image = Cockatiel 3.jpg
| image_caption = A male cockatiel
| image2 = Cockatiel (Female).jpg
| image2_caption = A female cockatiel
| genus = Nymphicus
| parent_authority = [[Johann Georg Wagler|Wagler]], 1832
| species = hollandicus
| authority = ([[Robert Kerr (writer)|Kerr]], 1792)
| display_parents = 2
| range_map = Bird range cockatiel.png
| range_map_caption = Red: all-year resident
| synonyms = ''Psittacus hollandicus'' {{taxobox authority | author = Kerr |date= 1792}}<br />
''Leptolophus hollandicus''
{{Listen|filename=Nymphicus hollandicus call.ogg|title=Cockatiel calling|description= Recording of a cockatiel|embed=yes|format=[[ogg]]}}
}}

The '''cockatiel''' ({{IPAc-en|%|k|Q|k|@|"|t|i:|l}};<ref>{{Cite book|title=Collins English Dictionary|publisher=HarperCollins|year=2018|isbn=978-0-008-28437-4|edition=13th|chapter=cockatiel}}</ref> '''''Nymphicus hollandicus'''''), also known as the '''weero'''/'''weiro'''<ref>{{Cite book |last=Australia |first=HarperCollins Publishers |url=https://books.google.com/books?id=JAI-AAAAYAAJ&q=%22weero%22+%22nymphicus%22 |title=Australia's Amazing Wildlife |date=1985 |publisher=Bay Books |isbn=978-0-85835-830-0 |language=en}}</ref><ref>{{Cite book |last1=Gray |first1=Jeannie |url=https://books.google.com/books?id=z6ia8rqTa7EC&dq=%22weero%22+%22nymphicus%22&pg=PA131 |title=Australian Bird Names: A Complete Guide |last2=Fraser |first2=Ian |date=2013-05-15 |publisher=Csiro Publishing |isbn=978-0-643-10470-9 |language=en}}</ref> or '''quarrion''',<ref>{{Cite book |last=Esser |first=A. |url=https://books.google.com/books?id=3kPUBwAAQBAJ&dq=quarrion+-wheat&pg=PA85 |title=Behavior and Environment: The Use of Space by Animals and Men |date=2012-12-06 |publisher=Springer Science & Business Media |isbn=978-1-4684-1893-4 |language=en}}</ref><ref>{{cite book |last1=Pizzey |first1=G. |last2=Doyle |first2=R. |title=A Field Guide to the Birds of Australia |date=1980 |publisher=Collins Publishers |location=Sydney |isbn=0-7322-2436-5 |page=177}}</ref> is a small-sized<ref>
[https://cockatielworld.co.uk/cockatiel-size/#:~:text=Cockatiels%20usually%20measure%20between%2012,they%20are%20beloved%20pets%20worldwide.|General Overview of Cockatiel Size, cockatielworld.co.uk]</ref>
[[parrot]] that is a member of its own branch of the [[cockatoo]] family [[endemism in birds|endemic]] to [[Australia (continent)|Australia]]. They are prized as exotic household [[pet]]s and [[companion parrot]]s throughout the world<ref>[https://www.merriam-webster.com/dictionary/exotic. General definition of the word exotic]</ref> and are relatively easy to breed compared to other parrots. As a caged bird, cockatiels are second in popularity only to the [[budgerigar]].<ref name="ausmus">{{cite web |url=http://birdsinbackyards.net/species/Nymphicus-hollandicus |title=Factsheets:Cockatiel |access-date=2008-08-30 |publisher=[[Australian Museum]] |archive-url=https://web.archive.org/web/20110613100433/http://birdsinbackyards.net/species/Nymphicus-hollandicus |archive-date=2011-06-13 }}</ref>
[[File:Cockatiel 2023 3 12.webm|frameless|right|thumbtime=13|alt=In a cage]]

The cockatiel is the only member of the [[genus]] ''Nymphicus''. It was previously unclear whether the cockatiel is a crested [[parakeet]] or small cockatoo; however, more recent molecular studies have assigned it to its own subfamily, '''Nymphicinae'''. It is, therefore, now classified as the smallest subfamily of the [[Cacatuidae]] (cockatoo family). Cockatiels are native to Australia, favouring the Australian wetlands, scrublands, and bushlands. There are many different mutations of this bird.

== Taxonomy and etymology ==
{{Wiktionary}}
Originally described by J. F. Gmelin in an edition of Systema naturae in 1788 as ''Psittacus novaehollandiae'', and after by Scottish writer and naturalist [[Robert Kerr (writer)|Robert Kerr]] in 1792 as ''Psittacus hollandicus'', and finally moved to its own genus, ''Nymphicus'', by [[Johann Georg Wagler|Wagler]] in 1832.<ref>{{cite book | vauthors=((Linné,  Carl von)), ((Gmelin,  Johann Friedrich)), ((Beer,  Georg Emanuel.)) | date= 1788 | title=Systema naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis | publisher=Impensis Georg. Emanuel. Beer | volume=1 | url=https://www.biodiversitylibrary.org/page/2896928}}</ref><ref>{{cite book | vauthors=((Linné,  Carl von)), ((Gmelin,  Johann Friedrich)), ((Kerr,  Robert)), ((Archer,  J.)) | date= 1792 | title=The animal kingdom, or zoological system, of the celebrated Sir Charles Linnæus. containing a complete systematic description, arrangement, and nomenclature, of all the known species and varieties of the mammalia, or animals which give suck to their young | publisher=Printed for A. Strahan, and T. Cadell, London, and W. Creech, Edinburgh | url=https://www.biodiversitylibrary.org/page/38664580}}</ref><ref>{{cite book | vauthors=((Wagler,  Johann Georg)) | date= 1832 | title=Monographia Psittacorum | publisher=s.n | url=https://www.biodiversitylibrary.org/page/35991466}}</ref> Its genus name reflects the experience of one of the earliest groups of [[Europe]]ans to see the birds in their native [[habitat (ecology)|habitat]]; the travellers thought the birds were so beautiful that they named them after mythical [[nymphs]]. The [[specific name (zoology)|specific name]] ''hollandicus'' refers to [[New Holland (Australia)|New Holland]], a historical name for Australia.

Its biological relationships were for a long time uncertain; it is now placed in a [[monotypic]] [[subfamily]] Nymphicinae, but was sometimes in the past classified among the [[Platycercinae]], the broad-tailed parrots. This issue was settled with molecular studies. A 1984 study of protein allozymes signalled its closer relationship to cockatoos than to other parrots,<ref name=adams1984>{{cite journal|year=1984|title=Biochemical systematics of the Australian cockatoos (Psittaciformes: Cacatuinae)|journal=Australian Journal of Zoology |volume=32|issue=3|pages=363–77|doi=10.1071/ZO9840363|last1=Adams|first1= M|last2=Baverstock|first2=PR|last3=Saunders|first3=DA|last4=Schodde|first4=R|last5=Smith|first5=GT}}</ref> and [[mtDNA|mitochondrial]] 12S [[rRNA]] [[DNA sequence|sequence]] data<ref>Brown, D.M. & Toft, C.A. (1999): [https://www.academia.edu/364859/Molecular_Systematics_and_Biogeography_of_the_Cockatoos_Psittaciformes_Cacatuidae_ Molecular systematics and biogeography of the cockatoos (Psittaciformes: ''Cacatuidae'')]. Auk 116(1): 141-157. {{JSTOR|4089461}}</ref> places it among the [[Calyptorhynchinae]] (dark cockatoos) [[subfamily]]. The unique, [[parakeet]] (meaning long-tailed parrot) morphological feature is a consequence of the decrease in size and accompanying change of [[ecological niche]].

Sequence analysis of [[intron]] 7 of the [[nuclear DNA|nuclear]] ''β''-[[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]].<ref>Astuti, Dwi (2004): [http://www.ees.hokudai.ac.jp/coe21/J/study/17RA/dwi.pdf 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.</ref>

The 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 (which precludes the display of blue and green structural colours), and facial feathers covering the sides of the beak, all of which are rarely found outside the family Cacatuidae.  This biological relation to other cockatoos is further supported by the existence of at least one documented case of a successful [[hybrid (biology)|hybrid]] between a cockatiel and a [[galah]], another cockatoo species.<ref>{{Cite web|url=https://www.talkingbirds.com.au/world-firsts/galatiel-php/world-first-galah-breeds-with-cockatiel|title = Talking Birds}}</ref>

== Distribution and habitat ==
[[File:Nymphicus hollandicus -perching on wires -Australia-6a.jpg|thumb|Wild cockatiels, Australia]]
Cockatiels are native to Australia, where they are found largely in [[arid]] or [[semi-arid]] country but always close to water. Largely nomadic, the species will move to where food and water is available.<ref name="ausmus" /> They are typically seen in pairs or small flocks.<ref name="ausmus" /> Sometimes, hundreds will flock around a single body of water. Wild cockatiels typically eat seeds, particularly ''[[Acacia]]'', [[wheat]], [[sunflower]] and ''[[Sorghum]]''.<ref name="worldparrottrust">{{cite web |title=COCKATIEL (Nymphicus hollandicus) |url=https://www.parrots.org/encyclopedia/cockatiel |publisher=World Parrot Trust |access-date=7 March 2022}}</ref> To many farmers' dismay, they often eat cultivated crops. Cockatiels may be observed in and around western [[New South Wales]] and [[Queensland]], [[Alice Springs, Australia|Alice Springs]], [[The Kimberley]] region and the northwestern corner of [[Western Australia]]. They are absent from the most fertile southwest and southeast corners of the country, the deepest [[Western Australia]]n deserts, and [[Cape York Peninsula]].

== Description ==

=== Appearance ===

The cockatiel's distinctive [[Crest (feathers)|crest]] expresses the animal's 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 crest is also held flat but protrudes outward in the back when the cockatiel is trying to appear alluring or flirtatious. When the cockatiel is tired, the crest is seen positioned halfway upwards, with the tip of the crest usually curling upward.<ref>{{Cite web|title=How to Understand a Cockatiel by His Crest|url=https://pethelpful.com/birds/How-to-Understand-a-cockatiel-by-his-crest|access-date=2020-08-22|website=PetHelpful|language=en}}</ref> In contrast to most cockatoos, the cockatiel has long tail feathers roughly making up half of its total length. At {{convert|30|to|33|cm|in|0|abbr=on}}, the cockatiel is the smallest of the cockatoos, which are generally larger at between {{convert|30|and|60|cm|in|0|abbr=on}}.

[[File:Brehms Tierleben Cockatiels.jpg|thumb|left|1927 [[Brehms Tierleben]] painting]]
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,<ref>{{cite web |last1=Chua |first1=Alex |title=How to Identify A Cockatiel's Gender |url=https://cleverpetowners.com/how-to-identify-a-cockatiels-gender-male-and-female-differences/ |website=Clever Pet Owners |date=25 August 2021 |access-date=2 December 2021}}</ref> and both sexes feature a round orange area on both ears, often referred to as "cheddar cheeks". This orange colouration is generally vibrant in adult males, and often quite muted in females. Visual sexing is often possible with this variant of the bird.

=== Sexual dimorphism ===
Most wild cockatiel chicks and juveniles look female, and are virtually indistinguishable from the time of hatching until their first [[moulting]]. They display horizontal yellow stripes or bars on the [[ventral]] surface of their tail feathers, yellow spots on the ventral surface of the primary flight feathers of their wings, a grey coloured crest and face, and a dull orange patch on each of their cheeks. However some modern-day mutations are sex linked and the male and female chicks are easily distinguishable as soon as their feathers come in.

Adult cockatiels with common coloring (grey body with yellow head) are [[sexual dimorphism|sexually dimorphic]], though to a lesser degree than many other avian species. This is only evident after the first moulting, typically occurring about six to nine months after hatching: the male loses the white or yellow barring and spots on the underside of his tail feathers and wings. The grey feathers on his cheeks and crest are replaced by bright yellow feathers, while the orange cheek patch becomes brighter and more distinct. The face and crest of the female will typically remain mostly grey with a yellowish tint, and a less vibrant orange cheek patch. Additionally, the female commonly retains the horizontal barring on the underside of her tail feathers.

The colour in cockatiels is derived from two [[pigment]]s: [[melanin]] (which provides the grey colour in the feathers, eyes, beak, and feet), and [[psittacofulvin]]s (which provide the yellow colour on the face and tail and the orange colour of the cheek patch). The grey colour of the melanin overrides the yellow and orange of the psittacofulvins when both are present.

The melanin content decreases in the face of the males as they mature, allowing the yellow and orange psittacofulvins to be more visible, while an increase in melanin content in the tail causes the disappearance of the horizontal yellow tail bars.

In addition to these visible characteristics, the vocalisation of adult males is typically louder and more complex than that of females. But like most things this is not a hard and fast rule.

=== Colour mutations ===
{{Main|Cockatiel colour genetics}}
Worldwide there are currently 22 cockatiel colour [[mutation]]s established in [[aviculture]], of which eight are exclusive to Australia. Mutations in captivity have emerged in various colours, some quite different from those observed in nature. Wild cockatiels are grey with visible differences between males and females. Male grey cockatiels typically have yellow heads while the female has a grey head. Juveniles tend to look like females with pinker beaks. The pied mutation first appeared in California in 1949. This mutation is a blotch of colour on an otherwise solid-coloured bird. For example, this may appear as a grey blotch on a yellow cockatiel.

Lutino colouration was first seen in 1958. These birds lack the grey of their wild counterparts and are white to soft yellow. This is a popular colour; due to inbreeding, these cockatiels often have a small bald patch behind their crests. The cinnamon mutation, first seen in the 1950s, is very similar in appearance to the grey; however, these birds have a warmer, browner colouring. Pearling was first seen in 1967. This is seen as a feather of one colour with a different coloured edge, such as grey feathers with yellow tips. This distinctive pattern is on a bird's wings or back. The albino colour mutation is a lack of pigment. These birds are white with red eyes. Fallow cockatiels first appeared sometime in the 1970s. This mutation shows as a bird with cinnamon colouring with yellow sections. Other mutations include emerald/olive, dominant and recessive silver, and mutations exclusive to Australia: Australian fallow, faded (west coast silver), dilute/pastel silver (east coast silver), silver spangle (edged dilute), platinum, suffused (Australian olive), and pewter. Other mutations, such as face altering mutations, include whiteface, {{not a typo|pastelface}}, dominant yellow cheek, sex-linked yellow cheek, gold cheek, cream face, and the Australian yellow cheek.

Cockatiel colour mutations can become even more complex as one bird can have multiple colour mutations. For example, a yellow lutino cockatiel may have pearling – white spots on its back and wings. This is a double mutation. An example of a quadruple mutation would be cinnamon cockatiel with yellowface colouring with pearling and pied markings.<ref>{{Cite book|url=https://archive.org/details/completebookofco00grin|url-access=registration|title=The Complete Book of Cockatiels|publisher=Wiley|isbn=978-0-87605-178-8|last1=Grindol|first1=Diane|date=1998-07-20}}</ref>

<gallery mode="packed">
File:Female Pearl Cockatiel.jpg|Female pearl cockatiel
File:Tiel kiss.png|Two different-coloured male cockatiels
File:Daisy Flower Lutino Cockatiel.jpg|Female lutino cockatiel
File:Eddie, a 1.5 year old male cockatiel.png|1.5 year old male lutino cockatiel
File:Cockatiel Sleeping.jpg|A male white-faced cockatiel resting
</gallery>

=== Breeding and life span ===
Breeding is triggered by seasonal rainfall. Cockatiels nest in tree hollows near a source of fresh water, often choosing eucalyptus/gum trees. The hen lays 4-7 eggs, one every other day, which she incubates for 17–23 days. The chicks fledge after 5 weeks.<ref>{{Cite web|url=https://animaldiversity.org/accounts/Nymphicus_hollandicus/|title = Nymphicus hollandicus (Cockatiel)| website=[[Animal Diversity Web]] }}</ref> Cockatiels are the only cockatoo species which may reproduce by the end of their first year.

The cockatiel's average life span is 12 to 15 years,<ref name="lafeber">{{cite web |url=https://lafeber.com/vet/basic-information-sheet-for-the-cockatiel/ | last=Pollock | first=Christal |title=Basic Information Sheet: Cockatiel |publisher=LafeberVet |date= 2012 |access-date=June 26, 2023}}</ref> though in captivity and under appropriate living conditions, a cockatiel could be expected to live from 16 to 25 years.<ref>{{Cite web|
title=Cockatiels 101| author=Eleanor McCaffrey|url=http://www.cockatielcottage.net/basics.html |website=cockatielcottage.net}}</ref> The oldest living and confirmed specimen of cockatiel was reportedly 36 years old.<ref>{{cite journal|last=Brouwer|first=K.|author2=Jones, M.L.|author3=King, C.E.|author4=Schifter, H.|name-list-style=amp|year=2000|title=Longevity records for Psittaciformes in captivity|journal=International Zoo Yearbook|volume=37|issue=1|pages=299–316|doi=10.1111/j.1748-1090.2000.tb00735.x}}</ref>

<gallery mode="packed">
File:Nymphicus hollandicus MWNH 0584.JPG|Egg, Collection [[Museum Wiesbaden]]
File:PictureofSnowy2.jpg|One-day-old cockatiel chick
File:Young cockatiel.jpg|Young fledged cockatiel
File:Bird-4years.jpg|4.5-year-old male cockatiel
File:Galatiel.jpg|Three juvenile 'galatiels' (''N. hollandicus'' x ''E. roseicapilla''), a hybrid between a cockatiel and a [[galah]]
</gallery>

== Speech and vocalization ==
Cockatiels can be very vocal and learn many spoken words and phrases by mimicking. Usually, males are faster to learn speech, mimicking or singing; their calls are also more varied.{{Citation needed|date=October 2024}}

Cockatiels can also be taught to sing specific melodies, to the extent that some cockatiels have been demonstrated to synchronise their melodies with the songs of humans.<ref name="seki">{{cite journal |last1=seki |first1=Yoshimasa |date=3 September 2021 |title=Cockatiels sing human music in synchrony with a playback of the melody |journal=PLOS ONE |volume=16 |issue=9 |article-number=e0256613 |bibcode=2021PLoSO..1656613S |doi=10.1371/journal.pone.0256613 |pmc=8415583 |pmid=34478436 |doi-access=free}}</ref>  Others have independently learned to mimic household sounds, including alarm clocks, phones, tunes or other birds from the outdoors.<ref>{{Cite web |last=birdy |date=2022-05-28 |title=How to Get a Cockatiel to Like You [Proven Tips] |url=https://birdsology.com/how-to-get-a-cockatiel-to-like-you/ |access-date=2023-05-13 |website=birdsology |language=en-US}}</ref><ref>{{Cite web |title=Cockatiels: Some of the Most Popular Pet Birds |url=https://www.thesprucepets.com/cockatiels-as-pets-1236728 |access-date=2024-01-07 |website=The Spruce Pets |language=en}}</ref><ref>{{Cite web |last=Doering |first=Laura |date=2013-05-16 |title=Cockatiel Sounds Explained – Pet Birds by Lafeber Co. |url=https://lafeber.com/pet-birds/cockatiel-sounds/ |access-date=2024-01-07 |website=Lafeber® Pet Birds |language=en-US}}</ref>

== See also ==
* [[Normal grey cockatiel]]
* [[Cockatiel colour genetics]]
* [[Companion parrot]]
* [[Pied cockatiel]]
* [[Lutino cockatiel]]
* [[Budgerigar]]
* [[White-faced cockatiel]]
* [[Cockatoo]]
* [[Bronze Fallow Cockatiel]]

== References ==
{{Reflist|30em}}

== Further reading ==
* 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. [https://web.archive.org/web/20060519005713/http://www.ees.hokudai.ac.jp/coe21/J/study/17result/dwi.pdf PDF fulltext]
* {{Cite journal|title=Phylogenetic relationships within Cockatoos (Aves: Psittaciformes) Based on DNA Sequences of The Seventh intron of Nuclear β-fibrinogen gene|journal=Jurnal Biologi Indonesia|volume= 7 |issue=1|pages= 1–11|year=2011|author=Dwi Astuti|url=https://perbiol.files.wordpress.com/2014/08/7-1-1-11.pdf|issn=0854-4425}}
* [[Jim Flegg|Flegg, Jim]] (2002): ''Photographic Field Guide: Birds of Australia''. Reed New Holland, Sydney & London. {{ISBN|1-876334-78-9}}
* {{cite book |last=Martin |first=Terry |year=2002 |title=A Guide To Colour Mutations and Genetics in Parrots |publisher=ABK Publications |isbn=978-0-9577024-6-2}}
* {{cite book |last=Hayward |first=Jim |year=1992 |title=The Manual of Colour Breeding |publisher=The Aviculturist Publications |isbn=978-0-9519098-0-5}}

== External links ==
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{{Commons category|Nymphicus hollandicus}}
{{Wikispecies|Nymphicus hollandicus}}
* {{Wikiquote-inline}}
* [http://www.euronet.nl/users/hnl/ Inte Onsman's MUTAVI Research & Advice Group]
* [http://www.cockatiels.org/ Cockatiels – National Cockatiel Society]
* [http://talkcockatiels.com/ Cockatiel Information Forum and Bulletin Board] – Talk Cockatiels
* [https://4av.net/fa/cockatiel-sounds/ Cockatiels Sound Effects] – The sounds of male and female cockatiels in different conditions

{{Cockatiel mutations}}
{{Cockatoos}}
{{Psittacopasseres|Ps.|state=collapsed}}
{{Taxonbar|from=Q514809}}
{{Authority control}}

[[Category:Cockatiel| ]]
[[Category:Calyptorhynchinae]]
[[Category:Endemic birds of Australia]]
[[Category:Domesticated birds]]
[[Category:Parrots of Oceania]]
[[Category:Talking birds]]
[[Category:Birds described in 1792]]
[[Category:Articles containing video clips]]
[[Category:Taxa named by Robert Kerr (writer)]]