Genetics can be tricky for anyone who doesn't have a background in Biology or has never taken a genetics course. For that reason I will attempt to simplify the basics and provide a "crash" course in mendelian genetics to assist those who are truly interested in learning about Gouldian genetics. Learning can be rewarding not only because of the joy you get from understanding something so complex - but also because of the freedom to produce set clutches of babies based on your knowledge of the genetics and your birds.

If you are unfamiliar with terms commonly used in genetics, you can click HERE for a crash course.

If you are interested in Reverse Genetics, and have a mutation in mind and want to know what two birds paired together will give you said mutation, click HERE

Otherwise, let's get started!

Gouldian genetics can be divided into three basic categories:
1. Head Color
2. Breast Color and
3. Body Color

Head Color:
Gouldian's come in three head colors: Red, Black, and Orange (aka Yellow).



Red and Black head color can be understood as two “alleles” (varieties) of a single gene located on the sex chromosome. Because this gene is sex linked, males can either be “single factor” or “double factor” for each, whereas females can only ever be “single factor.” The Orange Head trait is autosomal recessive. What this means in a nutshell is that birds can potentially possess one or all traits associated with head color. Sound confusing? It's not really, I promise!

Red Head (RH): Red Head is sex-linked dominant. Because of this, hens can only be SF and express it, while cocks can either be SF or DF for the trait.

Black Head (BH): The alternative form (though which, Black or Red, is really the "mutation," is wildly debated and not completely understood), is Black Head, and is sex-linked recessive. So like RH, hens can only be SF and express the trait while cocks can either be SF or DF for Black Head. In a nutshell, this means that SF Red head cocks are inherently "split" for the Black Head trait.

Orange Head (OH): Orange Head is an autosomal recessive trait but also requires at least one red head allele to be present in order to be expressed (e.g., R- oo). If a bird has two orange head genes but no red head allele (it is genetically black head instead), it will have a black head with an orange tipped beak (OTB). This occurs because the bird is genetically an orange headed bird, but it cannot express the orange color because the orange head color depends in part on the red head color for expression, and the red head color is not there. Both cocks and hens can be "split" for orange head.

For more information on what sort of chicks can be produced based on head color pairings, click here.

Breast Color:
Gouldians come in three recognized breast colors:
1. Purple
2. Lilac and
3. White

These traits can be understood as different "alleles" of one gene. Meaning - breast color is defined by one gene, and there are three different alleles (read: varieties) available - one for Purple, one for Lilac and one for White. This means that no bird can ever be triply split for each allele. i.e., no purple/white/lilac bird will ever exist!

Purple Breast: Purple breast is an autosomal dominant trait to both lilac and white. Cocks and hens can both be SF or DF for Purple breast. Any bird that possesses at least one copy of the purple allele will always be visually purple breasted. The only way to know if your bird is split for lilac or white is by test breeding it to a lilac or white bird - if you get lilac or white babies, you know your bird is split!

Lilac Breast: Lilac breast is recessive to Purple but dominant to White. A bird that is visually Lilac Breast will either be DF Lilac or Lilac/White.

White Breast: White breast is recessive to both Purple and Lilac. The only way a bird will be visually white breasted is if it is DF for the White allele (no visually WB bird will be "split" for any of the other two breast colors).

For more information on possible chick outcomes based on breast color pairings, click here.

Body Color:
Body Color genetics is where things start to get confusing. Gouldian hens come in four different body colors: Green, Yellow, Blue and Silver. Gouldian cocks come in six different body colors: Green, Dilute (SF Yellow), Yellow, Blue, Pastel and Silver. Briefly, the reason cocks come in more colors is due to the sex-linked Yellow mutation. This will be explained more later. At the end of the body color explanations there will be a link available which will explain some of the possible combinations that can be produced based on the body colors of the parents.

Certain body colors affect the expression of other pigments. I.e., the yellow body color gene prevents the expression of black pigment, while the presence of two recessive blue genes inhibits the expression of red and orange coloration. A link to a separate section describing pigmentation and how the genes affect it is found at the end of this page.

Normal aka Green Body:

Green body can be considered the "wild type", and is also referred to as "normal body." The green body color is due to a combination of genes, pigments, and structural colors which result in the green color we see. Often, you will see green body described as "sex-linked dominant" which is probably an effort to avoid confusion, though it is not entirely accurate. The genes, et.al., responsible for the green body coloration are incompletely (a.k.a. co-) dominant to yellow body, and dominant to blue body.

Yellow Body:

Yellow Body is a sex-linked gene which is incompletely dominant to the green wild type. Because it is a sex-linked gene, cocks can be DF or SF for Yellow while hens can only ever be SF. The gene responsible for yellow body interferes with the expression of black pigment, so any area which would normally be black on a green bird appears smokey gray or white/off-white on a yellow bird. This is why genetically black headed yellow birds appear to have white or near-white heads (as seen on the cock pictured above and below).

Keep in mind - a cock will only be visually yellow if he is DF for the yellow gene, or if he is SF Yellow with a White or Lilac breast. You can guess whether a yellow bird with a white or lilac breast is SF or DF by checking the color of his bib. In a SF male this will appear grey in color, in a DF bird it will be almost white; because the two yellow genes are completely blocking the expression of black pigment.

Dilute Body:


Dilute body results in a cock that inherits a single yellow gene. Dilute body only occurs in purple-breasted cocks. The single yellow body gene, being co-dominant to green body color, results in a partial masking of the green body coloration - so a little of each is expressed making the bird an "in-between" green and yellow. (Two yellow genes would would result in 100% masking of green body color, producing an all over yellow bird) Dilutes do not occur in white or lilac breasted cocks. A dilute male will only exhibit partial masking of black pigmentation, so the bib (or black head color) will appear grey. To be clear - a dilute male is essentially "SF Yellow," however, the phrase "SF Yellow" is usually reserved to describe cocks that are "SF Yellow" with white or lilac breasts, and thus appear visually yellow.

Blue Body:

Blue body is an autosomal recessive gene, so both cocks and hens can be DF and express the color blue or SF and be "split" for blue body. The bird will only appear blue in color, however, when it is strictly green in body color (as opposed to yellow or dilute) and is also DF for the blue body gene. This body color can occur in combination with any head or breast color, however, because the blue gene suppresses the expression of red and orange, any bird with a genetically red or orange head will appear to have a salmon or caramel colored head, and the normally yellow belly will appear beige or off-white.

Pastel (aka Blue Dilute) Body:

Pastel occurs in birds that carry a single yellow gene (in cocks only) and are also genetically blue bodied. Pastel only occurs in purple-breasted cocks. As with Dilutes, the normally black area(s) on the bird will appear grey (as opposed to white), so black headed birds will have grey heads, and the normally black bib of red/orange headed birds will be grey. Also, because the blue genes suppress the expression of red and orange, any areas of the bird which would normally be red or orange (such as the head or also yellow belly of the bird) will appear salmon or off-white, respectively.
Because the single yellow gene only partially masks green body, black pigmentation, and structural blue color, the overall look of the bird is a light blue color. This is how the descriptions "Blue Dilute" and "Powder Blue" are derived. Since females can only be SF for yellow, the yellow completely inhibits green, black and structural blue; while the blue genes inhibit red and yellow pigment, resulting in a bird which lacks the ability to produce most pigments and you get a "silver" bird. This is why hens can never be pastel.

Silver Body:

Silver body can occur in both cocks and hens and is the result of yellow body genes being combined with blue body genes. A genetically yellow bodied blue bird will appear silver in phenotype. (Note: A SFYB DF blue cock will only appear silver if he is white breasted, otherwise he will appear pastel as explained above.) It is easy to understand why these birds are silver by going back to previous discussion of what colors suppress others. So - because the yellow gene masks green body and suppresses the expression of black coloration; and because the blue genes suppress the expression of red and orange/yellow, the bird is left with nearly all colors being canceled out, and the entire body of the bird appears grey to "silver" in color. The purple of the chest is not affected, however, and red or orange headed birds will have salmon colored (not white) heads. Therefore, in order to achieve a bird which is nearly all white, you would need to produce a genetically black headed, white breasted, yellow bodied blue bird. To get the brightest silver coloring, cocks should preferably be DF for Yellow body.

For more information on what sort of chicks can be produced based on parent body color pairings, click here.

For those of you who are interested in diving a little deeper to a more advanced discussion of color genetics, you can click HERE.

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