Puffins belong to a family of 22 species of seabirds called Auks, pigeon-sized birds that live on a diet of small fish and crustaceans. Puffins catch their prey by swimming underwater and chasing it down. There are four species of puffins. One species, the Atlantic puffin, is around 18-20 cm (7-7.8 inches) in height and weighs between 350-600 grams (.8-1.3 pounds). It is found across a wide geographic area, all the way from France to the Gulf of Maine.