While the snow still clings to the cliffs of Bird Rock and Bonaventure Island in the Gulf of St. Lawrence, large seabirds come in flocks to build their nests on the windswept ledges. They are northern gannets (Morus bassanus or Sula bassana), the only northern representative of the gannet and booby family, Sulidae. The largest seabirds in the northern Atlantic, northern gannets are up to 40 inches (100 centimeters) long. They nest on islands in Canada, Greenland, Iceland, and northeastern Europe. The two southern species are slightly smaller. The Australian gannet (M. serrator) breeds on land around Tasmania and New Zealand, and the Cape gannet (M. capensis) breeds on islands off South Africa. Gannets and boobies are related to pelicans and cormorants.
Adult gannets have white plumage with black-tipped wing feathers. They have a tapered beak and a pointed tail. Excellent fliers and gliders, they spend most of their lives over water. To catch fish and squid, they dive into the sea from great heights with their wings half-closed. They nest in large colonies on cliffs.
Boobies also are sea dwellers that catch fish and squid by plunging into the water from far above the surface. Some boobies also catch flying fish in midair. Boobies are about 25 to 35 inches (65 to 85 centimeters) long, with long bills and long, narrow wings. They nest in colonies. There are several species, all tropical. The red-footed booby (Sula sula), the brown booby (S. leucogaster), and the masked, or blue-faced, booby (S. dactylatra) are wide-ranging in the Atlantic, Pacific, and Indian oceans. The blue-footed booby (S. nebouxii) is found in the Pacific from southern California to northern Peru and on the Galápagos Islands.