Whiteface Cockatiels: Genetics and Heredity

The whiteface cockatiels mutation is created by an autosomal recessive gene that deactivates the production of the yellow pigments. Basically, all yellows and oranges are totally absent in the whiteface and it is apparent even in the newly hatched chick of this mutation. As soon as a chick hatches a whiteface bird can be determined by the white down. All other colours have yellow down except for the whiteface.

In parrots this mutation is referred to as 'blue'. As most people are aware that yellow and blue make green, in the usual green coloured parrot species when the yellow is removed we are left with basically blue. In cockatiels which are not green coloured but in fact grey, the gene still in effect removes the yellows and oranges but leaves a grey bird lacking the characteristic orange cheekpatches and yellow facial colouring.

For a cockatiel to be a whiteface bird.....ie have no yellow or orange colours ....it must have got a whiteface gene from both of it's parents and thus have a pair of whiteface genes. Recessive means that if it has only one gene from 1 parent and none from the other then the gene will not be able to express itself and thus the bird will be said to be split to whiteface. Therefore it is possible to breed visually whiteface cockatiels from two parents that do not look whiteface but do carry a single gene each and pass them on to the same chick.