WatchList Species Account for Ivory Gull (Pagophila eburnea) |
Qualifies for the list as a Red List Species
|Photo: Greg Homel, Natural Images
This circumpolar species breeds in northern Canada, Greenland, and in archipelagos north of the Russian Federation. It winters just south of the Arctic pack ice and appears as a vagrant in western Europe and Japan and China. The Ivory Gull is associated with ice edges and pack ice near islands where there is open water, nests colonially on cliffs and rocky islands and the sides of steep limestone ridges that may be as far as 35 miles from the coast and at an elevation as high as 6,000 feet. It occasionally nests in colonies with other seabirds.
During the nonbreeding season, the bird occurs solitarily or in small flocks. Though fish and invertebrates form the bulk of its diet, like other gulls it is a highly opportunistic feeder, scavenging faeces and carrion of seals killed by polar bears, offal from whales, walruses and seals, and garbage scavenged near Arctic settlements; in fact it is known to follow polar bears and Inuit hunters to scavange food. Most predation of Ivory Gulls is on eggs and young at the breeding colonies, accounting for the choice of remote sites for nesting.
The main predator is the arctic fox, which sometimes takes eggs and young from entire colonies; other predators include polar bear, Parasitic and Long-tailed jaegers, Snowy Owl, and Glaucous and Thayer’s gulls. Gyrfalcons are known to prey on adults. Long-standing colonies have a fertilizing effect that results in a relatively highly-developed vascular flora. Chicks are fed largely on small fish and crustaceans, caught at sea rather than near the nest. As for conservation, the first need is to get a better idea of the number of colonies and their sizes in the North American population. Also important is to determine the extent to which the species relies on one or two main wintering areas, so an international plan of protection can be developed for this circumpolar species.