A cere is a fleshy, often waxy area above a bird's beak.
Budgerigars are dimorphic because the males' ceres turn bright blue upon maturity, while the females' ceres turn tan. The female budgies' ceres also appear wrinkled, to a greater extent during periods of fertility.
Immature budgies have pale pinkish ceres which are smooth and shiny.
The nares are set within the cere.
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Photo of a male budgie's cere
