The cockatiel is the only member of the genus Nymphicus. It was previously considered a crested parrot or small cockatoo; however, more recent molecular studies have assigned it to the Cockatoo subfamily Calyptorhynchinae (commonly known as Dark Cockatoos). It is, therefore, now classified as the smallest of the Cacatuidae (Cockatoo family). Cockatiels are native to the outback regions of inland Australia, and favour the Australian wetlands, scrublands, and bush lands.
Sexual dimorphism
All wild cockatiel (also known as the Normal Grey Cockatiel) chicks and juveniles are phenotypically female, and virtually indistinguishable from the time of hatching until their first molting. 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 gray colored crest and face, and a dull orange patch on each of their cheeks.
Adult cockatiels are sexually dimorphic, though to a lesser degree than many other avian species. This is only evident after the first molting, 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 gray 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 gray, though also with an orange cheek patch. Additionally, the female commonly retains the horizontal barring on the underside of her tail feathers.
The color in cockatiels is derived from two pigments: Melanin (which provides the gray color in the feathers, eyes, beak, and feet), and lipochromes (which provide the yellow color on the face and tail and the orange color of the cheek patch). The gray color of the melanin overrides the yellow and orange of the lipochromes when both are present.
The melanin content decreases in the face of the males as they mature, allowing the yellow and orange lipochromes 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 vocalization of adult males is typically louder and more complex than that of females.
Portrayal
The Cockatiel's distinctive erectile crest expresses the animal's state of being. 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. In contrast to most Cockatoos, the Cockatiel has long tail feathers roughly making up half of its total length. At 300 mm to 330 mm (12 to 13 ins), the Cockatiel is the smallest and only parakeet type of Cockatoo species. The latter ranging between 300 mm to 600 mm (12–24 in) in length.
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 sexes feature a round orange area on both ear areas, often referred to as "cheek patches." 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.
Distribution and habitat
Cockatiels are native to Australia, where they are found largely in arid or semi-arid country, but always near water. Largely nomadic, the species will move to where food and water is available. They are typically seen in pairs or small flocks. Sometimes, hundreds will flock around a single such body of water. To many 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.
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 36 years old. Diet and exercise are major determining factors in cockatiel lifespan.
Colour mutations
Fifteen different Cockatiel colour mutations are currently established in aviculture, including Grey, Pied, Pearled, Cinnamon, Whitefaced, Lutino, Albino (aka. Whitefaced Lutino) and Yellowcheeked Cockatiels.
Aviculture
Cockatiels are generally regarded as good pets. Like most other pets, the manner in which the animal is raised, handled, and kept along with inherited "personality" traits have 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. If handled often and if they have a patient owner, cockatiels become tame very quickly compared to some other parrot species.
