Possible Clues:

• Brilliantly coloured birds of tropical America
• Brilliantly coloured birds with very large beaks
• Those billed for Guinness ads?
• They're billed a huge amount for pressing uniform roughly
• Ones who can't change large bills?
• Sam the Froot Loops mascot and others
• Big-billed birds on cereal boxes
• Tropical birds known for their huge beaks
• Birds with large beaks
• The sound of the cancan, perhaps? That's for the birds