Atlantic puffin
Puffins breed in colonies on coasts and islands; several current or former island breeding sites are referred to as Puffin Island. The male Atlantic puffin builds the nest and exhibits strong nest-site fidelity. Both sexes of the horned puffin help to construct their nest. Horned puffin burrows are usually about deep, ending in a chamber, while the tunnel leading to a tufted puffin burrow may be up to long. The nesting substrate of the tufted and Atlantic puffins is soft soil, into which tunnels are dug; in contrast, the nesting sites of horned puffins are rock crevices on cliffs. The Atlantic puffin burrow is usually lined with material such as grass, leaves, and feathers but is occasionally unlined. The eggs of the Atlantic puffin are typically creamy white but the occasional egg is tinged lilac.