Beaks, bills, bird noses—whatever you wish to call them—they are important to every bird. ((FYI: The visible portion of the bill is called the rhamphotheca. The bill actually does extend inside the face.)) They are full of live tissues, regenerating after billing (a puffin’s form of kissing / affection where they rub bills together), bill-wiping (to clean their bills—typically on rocks or hard surfaces), eating, and defending their young. The tips of bird beaks grow constantly due to continual wear and tear. Some bird’s beaks even grow longer according to the season. The beak of the Puffin is one example of seasonal change. While it does not change in size, it changes in color. Puffins molt the the colorful outer sheath of their bills after breeding (seasonally). Their beaks brighten or fade in color when the old skin is worn down and the new layers are revealed depending on which season it happens to be. Maybe they do not need the extra attention they receive with their bright colorful beaks after they have wooed their loves and mated for the season. Perhaps it becomes a liability—making them more susceptible to predators.
Nares (nostrils) are often on the upper part of the beak. These can vary depending on the bird and its needs. For example, some birds have a protective flap, the operculum, covering part of the nostrils. This is helpful in keeping debris out. ((Podulka, Sandy, Ronald W. Rohrbaugh, Jr., and Rick Bonney, Editors. Handbook of Bird Biology. 2nd edition. Ithaca, NY: Cornell Lab of Ornithology, 2004.)) To each bird their own beak.
Most birds have black beaks and bills. There are some birds who have colorful beaks such as the Common Merganser, the Ruddy Duck or the choughs from the Corvid Family of birds. Besides the Toucan, no other birds compare to the magnificently colorful beaked Puffins.
Podulka, Sandy, Ronald W. Rohrbaugh, Jr., and Rick Bonney, Editors. Handbook of Bird Biology. 2nd edition. Ithaca, NY: Cornell Lab of Ornithology, 2004.