Abstract')"( n 1989 when visiting another ;J} Cockatiel breeder, I spotted an unusually colored Cockatiel. It was an adult normal gray cock however its face and cheek patches were diluted. The rich yellow of a normal cock was diluted to a pale lemon and the orange cheeks were diluted to a pale peach. As the breeder had no plans for this bird, I purchased it hoping that it was a new mutation.
Initially I paired the cock to a Lutino hen but, unfortunately, the hen died prior to laying. I then paired it to a spare White-faced hen. They hatched and reared four chicks; three were White-faced but the other was a young normal gray which appeared to have diluted cheek patches. The bird turned out to be a cock and molted out to be identical to its father.
The White-faced chicks could easily be explained-the father must have been split for White-faced. The appearance of the young Pastel-faced caused me a few problems.
I then embarked on a breeding program to determine whether or not this was a genuine new color mutation and how it was passed from parent to young.
After several years I determined that the Pastel-faced was an Autosomal Recessive mutation when paired to non-White-faced birds. However, when paired to a White-faced or a split White-faced, it acted as a dominant gene.
Although the mutation is Autosomal Recessive and is inherited the same way as, for example, the Pied and the White-faced, it is new in that it is carried on the same pair of chromosomes as the White-faced color mutation. All the other Autosomal Recessive color mutations are carried in different matching pairs of chromosomes.
This is a first in the Cockatiel world but the phenomenon is known in other species, for example, in Budgerigars the dilute (black-eyed yellow) and the White-wing are carried on the same chromosomes.
For the Pastel-faced to be visible in Cockatiels without White-faced in them, the mutation must be present in both matching chromosomes. If the Pastel-faced mutation is present in one chromosome and White-faced is pre- sent in the other, then the Pastel-faced is dominant to the White-faced and the bird is a visual Pastel-faced.
It will be seen that there are two types of visual Pastel-faced, one that is pure and carries the mutation in both chromosomes and one that is half Pastel-faced and half White-faced (i.e, Pastel-faced split White-faced).
I have now bred the mutation into several other colors and this has shown me the overall effect of the Pastel-faced mutation. It affects the psittacin color pigments by diluting the rich yellows to a pale lemon color. This affects the entire body. The orange-red of the ear patches are diluted to a pale peach. It has no affect on the melanin gray or brown apart from reducing the affect of the yellow ground color, if present.
The affect of this mutation is most noticeable in the plumage of the face and head of cock birds in normal grays. The melanin present in a normal gray hen's face does inhibit the clarity of the Pastel-faced.
In other color mutations like the Lutino, Cinnamon Pearl and Pied, where no melanin appears in the face of either cock or hen, the Pastel-faced is just as striking in both sexes.
To date (February 1995) I have successfully combined the Pastel-faced with Lutino, Cinnamon, Pearl, Pied, Dominant Silver, Cinnamon Pied, Cinnamon Pearl, Cinnamon Pearl Pied and Lutino Pearl.
The Pastel-faced Dominant Silver is a striking bird and has provided me with the first true dilute Cockatiel-the Pastel-faced dilutes the yellow psittacin color pigments and the Dominant Silver dilutes the melanin gray.