Adults are similar in appearance to the western gull with a white head, dark, slate-colored back and wings, and a thick yellow bill.

Most are non-migratory, but an increasing number have been traveling to California's Salton Sea and southwards to Sonora during nonbreeding periods.

[5] Yellow-footed gulls nest on the beach, a few metres above the upper limits of the highest tides.

The nest is a scrape in the sand with a meagre lining of seaweed or dry plant material.

[5] The population is estimated at 60,000 individuals and appears to be stable, so the IUCN has rated the species as being of "least concern".