The cockatiel, Nymphicus hollandicus, or Quarrion, is a perfect avicultural subject. Originally from Australia, many thousands are reared commercially worldwide for the pet industry. The American Cockatiel Society has established a standard of excellence for the exhibition minded fancier. The cockatiel now occurs in six well-established mutations. These factors, three sex-linked recessive and three autosomal recessive, all affect the coloration of the plumage.
Some traits also change the eye color from black to red.
Many other color variants are reported. Some of these new colors are definite mutations in the process of becoming established. Others are simply combinations of pre-existing varieties or are imaginitive names used in sales pitches. The normal cockatiel is slate grey, reminiscent of a blue domestic pigeon. Some white extends from the wing butt down the outer edge of the wing.