Fee

Fee is a mutation in the United States and Europe that dilutes the pheomelanin (red pigment) in the feathers of coturnix quail, but leaves the eumelanin (black pigment). It does not affect the pattern of the feathers, but just the underlying color, diluting the bird to shades of black, white, and grey (1).

It was imported to the United States mixed in the German Pastel Collection before 2018 (2), and is believed to originate in Bavaria (2). It has never been studied in a scientific setting, though is common in backyard flocks outside of Australia. So far the locus is unknown, it is compatible with every other mutation in public hands, and there are no confirmed linkage groups.

It goes by a variety of different names, including Falb Fee (German for "Fallow Fairy") when on Pharaoh, Perl-Fee on Fawn ("Pearl Fairy"), and Grau Fee (or "Grey Fairy") on EB. They are called the same whether they have one or two copies of fee, though two copies are generally considered more desirable.

In homozygous form (two copies), the bird will be entirely black, white, and shades of grey. In heterozygous form (one copy of fee, one "natural"), the plumage will be mainly shades of black and white, though there will be some color leakage. In both forms, the fee is clearly visible.

The proposed gene symbol is F, and the order of dominance is Fee > Wildtype.

Breeding with Fee:

Homozygous Fee x Homozygous Fee = 100% Homozygous Fee

(F/F x F/F = 100% F/F)

Homozygous Fee x Wildtype = 100% Heterozygous Fee

(F/F x f+/f+ = 100% F/f+)

Homozygous Fee x Het. Fee = 50% Homozygous Fee, 50% Heterozygous Fee

(F/F x F/f+ = 50% F/F, 50% F/f+)

Heterozygous Fee x Het. Fee = 25% Wildtype, 50% Heterozygous Fee, 25% Homozygous Fee

(F/f+ x F/f+ = 25% f+/f+, 50% F/f+, 25% F/F)

Heterozygous Fee x Wildtype = 50% Wildtype, 50% Heterozygous Fee

(F/f+ x f+/f+ = 50% f+/f+, 50% F/f+)

For more information about breeding with this kind of gene, including tips and tricks and a full explanation of how these results were calculated, please see here.