• Appearance: white head and belly, light grey back and wings,black wingtips spotted with white, yellow beak and legs, dark black ring on beak near nostrils, in winter has brown speckles on back of head
  • Male is larger than female, but no significant difference in coloration
• Length: 17-20 inches (about 1.75 feet)
• Wingspan: 41-46 inches (almost 3 feet)
• Status: common, populations increasing
  • Almost went extinct in 1800s because of hunting and habitat loss
  • Protection under 1918 Migratory Bird Treaty Act led to recovery
• Habitat
  • Naturally found in estuaries, beaches, and mudflats
  • They also inhabit urban, suburban, and agricultural areas
    • Found inland more commonly than most other gulls
    • Some ring-billed gulls never travel to the coast in their lifetime
  • Found in southern Canada, throughout United States, northern Mexico, depending on season
    • Currently extending breeding range, especially in western U.S., because of availability of food, much of which are discarded scraps
    • May become most common gull in North America, if it is not already
• Diet
  • Opportunistic feeders – eat almost anything they can find
  • Natural diet is mostly fish, but also eat insects, earthworms, rodents
  • Forage by walking on land; wading or skimming in shallow water; nabbing insects out of the air, and stealing food midair from other birds
  • In areas settled by humans, eat agricultural grains, seeds, berries, discarded food scraps, and food from landfills
    • Very comfortable around humans, may even steal food from children
  • Can get very sick or even die if they eat plastic pieces
• Migration
  • Spend summer in northern United States and southern Canada
  • Spring migration March-May, fall migration August-October
  • Overwinter in southern United States and northern Mexico
  • Increasing number of populations are becoming year-round residents due to human-provided availability of food, especially where there are open landfills
    • If landfills are closed and replaced with waste incineration systems population declines because of dependence on this food source
  • Cruise speed is 10-20 mph, but can fly over 40 mph
• Nesting
  • Nest in colonies of about 20 up to tens of thousands of breeding pairs
  • Normally choose one mate per year, but large colonies may have small percentage of males with two females – lay egg “super clutches”
  • Breeding pairs/trios usually return to site of hatching or from previous years
  • Sometimes hybridize with laughing gulls (right)
  • Ground nesters – depending on habitat, nest sites include sandbars, rocky beaches, driftwood, bare rock, concrete, or soil
  • Nest usually depression lined with twigs, sticks, grasses, leaves, lichens, mosses
  • Both parents build nest and care for chicks
  • Average brood is 2-4 olive-gray eggs per female, “super clutches” have 5-8 eggs
• “Young of the Year”
  • Start briefly leaving nest after about 2 days, gradually spend more time foraging out of nest
  • Fledglings learn to fly after about 5 weeks
  • Juveniles are brown and white with pink beak and legs, transition into adult feathers over three years
  • Brown speckles at back of head last to vanish, only to return after breeding season
  • Average lifespan 5-10 years, but oldest ring-billed gull was 28 years old