*Pallid* Cacatua galerita Eleonora??
In the R&D centre in Belgium, they have a female Cacatua galerita Eleonora (The Eleonora cockatoo, aka medium sulphur-crested cockatoo) with a different color of the beak, legs and nails. The color of the beak is grey, the legs and nails are light grey (in wildtype beak, legs and nails are completely black).
The bird is born with red eyes, which turned dark after a few days. The fact that these ‘paler’ birds are all females let us SUSPECT (for the sake of a good order: we did not examine any feathers or DNA of this bird), that it is most possible a sex-linked recessive mutation and (possible) a pallid mutation.
Pallid is a sex-linked recessive mutation that reduces the eumelanine for +/- 50% and pallid youngsters are born with red eyes and they turn dark after a few days. So the phenotype of this bird fits perfectly in this description. Of course, in this species, we can not see any eumelanin reduction in the feathers, since there is no melanin in it.
The owner is looking for breeders who maybe have the same mutation in their collection. Any info is welcome!