The Antarctic Fulmar, a common seabird of the Southern Hemisphere, is the "sister" of the Northern Fulmar (F. glacialis) in the Arctic. It is also known as the Southern Fulmar and looks much lighter than the Northern sister species. It is largely pale grey above and white below with a distinctive white patch on the wing. It breeds on the coast of Antarctica and on surrounding islands. It nests in colonies on cliffs, laying a single egg on a ledge or crevice. Its diet includes krill, fish and squid picked from the water's surface. Their population is not endangered and estimated to be around 4 million.