This is NOT moulting. It looks like she got her face dirty somehow.
Why is my budgies feathers changing Colour?Molting. Some parakeets molt more frequently than others, but it is normal for a parakeet to molt, or shed his feathers and replace them with new ones, once or twice a year. During this process, patches of new feathers emerge next to patches of old ones.
Sometimes, a male budgie will have a color change of the cere from blue to tan. This usually occurs because the budgie has a tumor of the testicle that is producing female hormones, resulting in the cere color change. Females with a tan cere may develop brown hypertrophy of the cere, a thickening of cere tissue.
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