Mallard plumage?

[Gamebird7]

I have a mallard drake who is a little under a year old and he still has not fully colored out. I have several younger drakes about 4 or 5 months old who already have their green heads and his is still a blackish green and he has a lot of brown juvinile feathers on his body. Is this genetics or nutrition? If it's genetics, are his offspring likely to have the same traits?

Thanks for any help.

Chad

[Patrick]

I've had one pop up occasionally in one of my lines, so I'd say that it is genetic. I have had some which did finally color up fully in their second year, and some which never did.

[Gamebird7]

Did their offspring have the same characteristics?