The Ross's Gull, Rhodostethia rosea, is a small gull, the only species in its genus, although it has been suggested it should be moved to the genus Hydrocoloeus, which otherwise only includes the Little Gull.

It breeds in the high arctic of northernmost North America, and northeast Siberia. It migrates only short distances south in autumn, most of the population wintering in northern latitudes at the edge of the pack ice, although some birds reach more temperate areas, such as north west Europe. In North America, a Ross's Gull has been spotted as far south as Salton Sea in California, although sightings this far south are extremely rare.

This small bird is similar in size and some plumage characteristics to the Little Gull. It is slightly larger and longer winged than that species, and has a pointed tail. Its legs are red. Summer adults are pale grey above and white below, with a pink flush to the breast, and a neat black neck ring. In winter, the breast tints and neck collar are lost.

Young birds resemble winter adults, but have a dark "W" pattern on the wings in flight, like young Little Gulls. The juveniles take two years to attain full adult plumage.

The Ross's Gull breeds on swampy Arctic estuaries, laying two to three eggs in a ground nest. It will eat any suitable small prey, and often feeds on mudflats like a wader.

This bird is named after the British explorer James Clark Ross.