Puffins become sexually mature at the age of three, but most do not mate until they're four. Juveniles moult during their first winter at sea, and again the following autumn. Adult puffins moult completely following the breeding season, and partially before breeding. When faced with an intruder close to their burrow, puffins open their bills and lower their head, and may follow this action with bill grappling or kicking. They have a limited range of calls, including a low grumbling noise heard usually from underground in breeding colonies.
Chicks often peep to indicate that they want food.
When conspecifics fight, they spread their wings, open their mouths wide, stomp their feet, and wrestle with their opponents. Such displays often draw crowds of birds to watch. Every year puffins over-winter out on the ocean. Their waterproof feathers and their ability to drink salt water and catch fish make staying long periods on the sea possible. They disperse widely while at sea but return to the colony where they were born, and usually to the same mate, every year for breeding.