Cockatiel's mutations
Cockatiel comes in many mutations. Some of them you can see here, we will update this topic with more mutations.
Normal cockatiel
Inheritance: Dominant
Body: Dark grey
Mask: Male have yellow facial mask and portion of yellow to the base of the crest. Hens will have the orange cheek patch and slight yellow on the face, edging the beak, around the eyes, and a dot on the forehead.
Both sexes will have the white wing bar on the side of the wing. Males can be darker than hens. Sometimes the splits that the cock carries can effect the depth of color to the facial mask and/ or body plumage.
Cinnamon cockatiel
Inheritance: Sex-linked recessive
Body: Pale ‘dusty' silver/brownish color.
Mask: The bright face and clear tail feathers of the male, as well as the immature and the females' dull face and barred tails is the same as for the normal grey.
Cinnamon is one of the most common colors apart from normal grey. It can be mistaken for a light grey, but has a browner overtone, and a paler, softer appearance. Some are a very obvious brown color too. In Cinnamons, the eumelanin pigment are partially oxidized (eumelanin granules are stopped at the brown stage of their development to end up in their natural black colour state)
Fallow cockatiel
Inheritance: Recessive
Body: Dusty brown color, though fallow tends more to the yellowish side than the cinnamon's brownish color.
Mask: The hen will have a subtle yellow face/head.
Eyes: Red
Fallow is very similar to the cinnamon, and they are hard to tell apart unless you have them side-by-side. The main difference between them is that the fallow colored birds have deep red eyes. At first glance, and even on close inspection, it often looks like the normal dark eyes. But get them in the right light (often a camera flash will bring them out, but look for a red IRIS, not the red pupil that happens in any colored eye hit with a camera flash!) and you will find they are actually a dark red color.
Pearl cockatiel
Inheritance: Sex-linked
Body: The pearl gene decreases the spread of grey pigments (melanin) and increases the spread of the yellow pigments. Melanin is absent from the center of each individual feather, it can vary in color from white to deep golden yellow creating a scalloped pattern. If you look carefully at an individual pearl feather, it can either be yellow with grey/dark edging, or grey/dark with yellow edging. The pearl pattern can be seen on the back, nape, and wings. There are both lightly pearled birds and heavily pearled birds. Starting with the first molt (starting at 5-6 months old), a male pearl will loose his markings and return to a normal gray coloration over a period of years. Males don't actually loose the pearling but it becomes so faint that it can only be seen on some of the heavily pearled mature males, and even then it only looks like a shadow. The female will not loose her markings.
Lutino cockatiel NEW!!!!
Inheritance: Sex-linked
Body: Colour of the body can vary from yellow to a cream white
Mask: It can vary from yellow to a cream white with orange cheek-patches.
Eyes: Red
Feet and nails: Flesh colored
Colour of the body can vary from yellow to a cream white with orange cheek-patches. Same colour will be present in the crest and sides of the face, and tail. The Lutino mutation lacks the melanin pigment, which enables the black, brown and grey colors.
The beak, feet and nails are flesh colored.