The Atlantic Puffin (Fratercula arctica), also known as the Common Puffin, is a species of seabird in the auk family. It is the only puffin native to the Atlantic Ocean; two related species, the Tufted Puffin and the Horned Puffin, are found in the northeastern Pacific. The Atlantic Puffin breeds in Iceland, Norway, Greenland, Newfoundland and many North Atlantic islands, and as far south as Maine in the west and the British Isles in the east. The Atlantic Puffin has a large population and a wide range. It is not considered to be endangered although there may be local declines in numbers. On land, it has the typical upright stance of an auk. At sea, they swim on the surface and feed mainly on small fish, which they catch by diving underwater, using their wings for propulsion.
The Atlantic Puffin has a black crown and back, pale grey cheek patches and white underparts. Its broad, boldly marked red and black beak and orange legs contrast with its plumage. It moults while at sea in the winter and some of the bright-coloured facial characteristics are lost. The external appearance of the adult male and female are identical except that the male is usually slightly larger. The juvenile has similar plumage but its cheek patches are dark grey. The juvenile does not have brightly coloured head ornamentation, its bill is less broad and is dark-grey with a yellowish-brown tip, and its legs and feet are also dark. Puffins from northern populations are typically larger than their counterparts in southern parts of the range. It is generally considered that these populations are different subspecies.
The Atlantic Puffin spends the autumn and winter in the open ocean of the cold northern seas and returns to coastal areas at the start of the breeding season in late spring. It nests in clifftop colonies, digging a burrow in which a single white egg is laid. The chick mostly feeds on whole fish and grows rapidly. After about six weeks it is fully fledged and makes its way at night to the sea. It swims away from the shore and does not return to land for several years.
Colonies are mostly on islands where there are no terrestrial predators but adult birds and newly fledged chicks are at risk of attacks from the air by gulls and skuas. Sometimes a bird such as an Arctic Skua will harass a Puffin arriving with a beakful of fish, causing it to drop its catch. The striking appearance, large colourful bill, waddling gait and behaviour of this bird have given rise to nicknames such as "clown of the sea" and "sea parrot". It is the official bird symbol for the Canadian province of Newfoundland and Labrador.