Chocobo colors

[impatient_cat]

I have one Chocobo left to make, but I don't know what color to make it. Currently I have two yellow ones, one black, and one blue. I don't have the resources to make another blue one. That said:
What color should that last Chocobo be?

Yellow
Red    
Black  
Green 
Some thing else entirely

EDIT: Here're the Blue and Black Chocobos