Ring-billed Gulls are often found in and around urban, suburban, and agricultural areas. In coastal areas, Ring-billed Gulls frequent estuaries, beaches, mudflats, and coastal waters. In winter, these birds are common around docks, wharves, and harbors. Ring-billed Gulls are more commonly seen inland than most other gull species. They can be found at reservoirs, lakes, ponds, streams, landfills, parking lots, and shopping malls.Back to top
Able to thrive on almost any available source of nutrition, Ring-billed Gulls eat mostly fish, insects, earthworms, rodents, grain, and garbage. Common fish prey include alewife, smelt, nine-spined stickleback, and yellow perch; insect meals feature primarily beetles, flies, dragonflies, and bugs. In the western U.S., many Ring-billed Gull populations find most of their food on farm fields, forgoing fish altogether. In addition to their more common fare, Ring-billed Gulls have been known to eat dates, cherries, blueberries, and strawberries, as well as French fries and other food discarded—or left unguarded—by people.Back to top
Ring-billed gulls nest in colonies numbering from 20 to tens of thousands of pairs. They build their nests on the ground near freshwater, usually on low, sparsely vegetated terrain. They may nest on sandbars, rocky beaches, driftwood, bare rock, concrete, or soil. They often choose sites near or underneath low plants to hide them from aerial predators. Nest sites tend to be used for multiple seasons, by new or returning pairs.
The male and female cooperate in constructing the nest—a scrape in the ground lined with twigs, sticks, grasses, leaves, lichens, or mosses. Some nests are minimalist affairs with almost no lining. The nest's outer diameter ranges from about 10 to 25 inches, with an inner cup about 9 inches in diameter and 2 inches deep.
|Clutch Size:||2-4 eggs|
|Number of Broods:||1 brood|
|Egg Length:||2.0-2.6 in (5-6.6 cm)|
|Egg Width:||1.4-1.8 in (3.6-4.6 cm)|
|Incubation Period:||20-31 days|
|Nestling Period:||4-5 days|
|Egg Description:||Pale olive gray with dark brown speckles.|
|Condition at Hatching:||Covered in camouflaged gray and brown down feathers; eyes open by end of the first day; may leave nest briefly by 2 days old.|
Ring-billed Gulls are strong, graceful flyers. They can race along at more than 40 miles per hour, and they're adept at snatching food from the air. You may see these birds hovering, soaring, or poised and stationary in the wind. Adults play by repeatedly dropping objects, then swooping to catch them—perhaps honing their hunting moves. These gulls use a wide variety of foraging methods: walking around on land; stamping their feet in shallow water to uncover small invertebrates; skimming shallow water for small fish; nabbing insects out of the air. They steal food from other birds, hunt for small rodents, and scavenge along beaches, parks, and garbage dumps. Birds in large nonbreeding groups usually space themselves evenly, about 3–6 feet apart. Like many other gull species, when Ring-billed Gulls are feeling aggressive they'll lower their head, begin calling, and then raise their head up to their shoulders. This can escalate to an exaggerated toss of the head over the back while calling. To signal submission, a Ring-billed Gull will draw its head back in toward its shoulders and make shorter, calmer calls, sometimes tossing its head up or away from its opponent as well.Back to top
After nearly succumbing to hunting and habitat loss, Ring-billed Gull populations increased in most areas between 1966 and 2014, according to the North American Breeding Bird Survey. The North American Waterbird Conservation Plan estimates a continental breeding population of 1.7 million birds, and rates the species a 5 out of 20 on the Continental Concern Score. Ring-billed Gull is not on the 2014 State of the Birds Watch List. These gulls can be found throughout the year in the U.S. and Canada, with some wintering in Mexico and other areas of Central America. Their populations plummeted during the late nineteenth century, when humans encroached on the birds' nesting grounds and killed them for feathers to decorate hats. By the early 1900s many breeding sites were defunct. Protection under the 1917 Migratory Birds Convention Act (Canada) and 1918 Migratory Bird Treaty Act (U.S.) helped bring the species back, and now this species once again thrives across the United States and southern Canada—so numerous in some places that they are considered pests. In the middle of the twentieth century, Ring-billed Gulls around Lake Ontario proved susceptible to the pesticide DDT and to PCB pollution. Environmental regulations in the 1970s helped reduce pollution levels. Humans have generally helped Ring-billed Gulls by providing extra foods, including introduced fish; insects and grain exposed on farm fields; and discarded food and refuse. The Ring-billed Gull continues to extend its breeding range—likely fueled in part by the edible garbage available at open landfills.Back to top
Dunne, Pete. 2006. Pete Dunne's essential field guide companion: Houghton Mifflin Harcourt.
Ehrlich, P. R., D. S. Dobkin and D. Wheye. 1988. The birder's handbook. A Field Guide to the natural history of North American birds, including all species that regularly breed north of Mexico. New York: Simon and Schuster, Inc.
Lutmerding, J. A. and A. S. Love. Longevity records of North American birds. Version 2015.2. Patuxent Wildlife Research Center, Bird Banding Laboratory 2015.
North American Bird Conservation Initiative. 2014. The State of the Birds 2014 Report. US Department of Interior, Washington, DC, USA.
Pollet, Ingrid L., Dave Shutler, John W. Chardine and John P. Ryder. 2012. Ring-billed Gull (Larus delawarensis), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Sibley, David Allen. 2014. The Sibley guide to birds, second edition. Alfred A Knopf, New York.