A Unique Gull: Red-Legged Kittiwake

Red-legged kittiwake on St. George Island, Alaska.

Of the more than 50 gull species found worldwide, only the kittiwakes are known to venture far out to sea. All the other species live and feed along coastal and inland areas. There are two species of kittiwake, the red-legged and black-legged kittiwakes. The black-legged kittiwake is far more common than its counterpart, nesting in coastal areas throughout the North Atlantic and Pacific Oceans, and wintering as far south as southern Japan, Baja California, Florida, and northern Africa. On the other hand, the red-legged kittiwake is confined to the Bering sea and North Pacific Ocean. They breed on just a few islands in Alaska and Russia and winter in the open ocean, often near the edge of sea ice. About 80 percent of their population breeds on the Pribilof Islands in Alaska.

From Robinson et al, 2019. Potential northward expansion of the breeding range of Red-legged Kittiwake Rissa brevirostris. Marine Ornithology: 47: 229–234.

Kittiwakes are relatively small as gulls go. They are both about the size of a crow, but the red-legged is a few inches smaller than the black-legged. Red-legged kittiwakes are not only distinguished by the color of their legs, but they also have a shorter bill and bigger eyes than black-legged kittiwakes. The larger eyes are thought to aid red-legged kittiwakes in hunting at night especially when searching for one of their preferred foods, squid. When they hunt, they form large groups called “melees” often with black-legged kittiwakes.

Red-legged kittiwake colony on St. George Island, Alaska.

Red-legged kittiwakes breed in colonies on steep, rocky cliffs up to 900ft high on islands in the Bering Sea, with other colony nesting sea birds including black-legged kittiwakes, puffins, and murres. When born, the chicks instinctively know to stay still so they do not fall from their nests on the steep cliffs. The colony on St. George Island, Alaska contains over 80% of the world’s population of red-legged kittiwakes. Given the restricted distribution of the species, limited breeding habitat, and decreasing population size, the species is listed as vulnerable.

Adult red-legged kittiwake on St. George Island, Alaska.