The Great Black-backed Gull (Larus marinus) is the largest gull in the world, which breeds on the European and North American coasts and islands of the North Atlantic.

It is 71–79 cm (28–31 in) long with a 1.5–1.7 m (4 ft 10 in–5 ft 7 in) wingspan and a body weight of 1.3–2.3 kg (2.9–5.1 lb), though large males may exceed this weight.

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The European Herring Gull (Larus argentatus) is a large gull (up to 26 inches or 66 cm long), and is the most abundant and best known of all gulls along the shores of western Europe. It breeds across Northern Europe, Western Europe, Scandinavia and the Baltic states. Some European Herring Gulls, especially those resident in colder areas, migrate further south in winter, but many are permanent residents, e.g. in the British Isles, Iceland, or on the North Sea shores.

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The Common Gull (European and Asian subspecies) or Mew Gull (North American subspecies) Larus canus is a medium-sized gull which breeds in northern Asia, northern Europe and northwestern North America. It migrates further south in winter.

Both Common and Mew Gulls breed colonially near water or in marshes, making a lined nest on the ground or in a small tree;

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The Iceland Gull, Larus glaucoides, is a large gull which breeds in the Arctic regions of Canada and Greenland, but not Iceland, where it is only seen in the winter. It is migratory, wintering from in the North Atlantic as far south as the British Isles and northernmost states of the eastern USA, as well as in the interior of North America as far W as the western Great Lakes. It is much scarcer in Europe than the similar Glaucous Gull.

These are omnivores like most Larus gulls, eating fish, molluscs, offal, scraps and eggs. These birds forage while flying, picking up food at or just below the water's surface, also feeds while walking or swimming.

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