The Wedge-Tailed Shearwater (Puffinus pacificus) is one of the most common seabirds in Hawaii. The wailing sound made by these birds at their burrows at night inspired its Hawaiian name, 'Ua'u kani, which means 'calling or moaning petrel'. Like other sherawaters, the birds cannot stand upright on their legs and have difficulty moving about on land. This species lays a single white egg in a burrow on the ground or in natural crevices. Kilauea NWR, Kaua'i, Hawaii.