- 15.7–16.9 in
- 42.5–47.2 in
- 15.8–24.2 oz
- Goéland sénateur, Mouette blanche (French)
- Gaviota marfil (Spanish)
- The Ivory Gull casts up pellets of indigestible matter from its food, such as bones and fur. Pellet-casting is most frequent where lemmings are abundant and are the major prey.
- The adult Ivory Gull attending the nest expels its faeces powerfully by aiming its cloaca outward from cliff nest sites.
- Large nests of the Ivory Gull are eaten by caribou during the winter and early spring.
- The oldest recorded Ivory Gull was at least 23 years, 11 months old when it was shot in Greenland in 2005. It had been banded in Nunavut in 1982.
Breeds on rocky islands and cliffs near pack ice. Winters on pack and drift ice.
Fish, marine invertebrates, some small mammals, carrion. Also feces and placentas of seals.
- Clutch Size
- 1–3 eggs
- Egg Description
- Dark to pale brown with variable amount of dark spotting and blotching.
- Condition at Hatching
- Alert and mobile, covered with white down.
Mound of mosses, dry grass, splinters of driftwood, feathers, down, stalks, algae or seaweeds, lichen, or dried mud. Placed on cliff ledges, dry stony ridges within a few meters of the ice cap, gently-sloping boulder-strewn mounds, or gravel banks in small streams.
Hovers, dips, and plunges into water to get food. Attracted by red splashes on snow. Follows whales. Scavenges carrion from polar bear kills.
Little information is available on Ivory Gull numbers and population trends because of the species' remote breeding and wintering areas. The North American Waterbird Conservation Plan estimates a continental breeding population of more than 2,400 birds, rates the species a 14 out of 20 on the Continental Concern Score, and lists it as a Species of Moderate Concern. Ivory Gull is on the 2014 State of the Birds Watch List, which lists bird species that are at risk of becoming threatened or endangered without conservation action.
- Haney, J. C., and S. D. MacDonald. 1995. Ivory Gull (Pagophila eburnea). In The Birds of North America, No. 175 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, and The American Ornithologists' Union, Washington, D.C.
- Kushlan, J.A., et al. 2002. Waterbird conservation for the Americas: the North American Waterbird Conservation Plan, version 1. Waterbird Conservation for the Americas. Washington, DC.
- North American Bird Conservation Initiative, U.S. Committee. 2014. State of the Birds 2014 Report. U.S. Department of Interior, Washington, DC.
- USGS Patuxent Wildlife Research Center. 2015. Longevity records of North American Birds.