I think the colors have to do with age. This is Mama T and she is on a good diet of veggies, frozen and fresh, fresh fruit, pellets, and nuts.

The blue on her is turning very green but I believe that is old age not diet.
She has arthritis in her beak and talons and is not tame. We hate to move her to much afraid of what the stress will do to her. She is wild caught.
How lucky are you to be able to care for your new aging friend.
I really think for his age Raw looks really good and a good diet well help him to live to be 70 plus years too like Mama T.