Ring-billed Gull

The Ring-billed Gull, Larus delawarensis, is a medium-sized gull with a distinctive dark ring encircling its yellow bill. The species exhibits a white head, neck, and underparts, while the back and wings are a sleek silver gray. The legs are a bright yellow, complementing the yellow eyes surrounded by red rims. This bird undergoes a transformation over three years to attain its breeding plumage, with each annual moult altering its appearance.

Identification Tips

Adult Ring-billed Gulls are recognized by their yellow bill with a black ring, a feature from which they derive their name. They measure between 16.9–21.3 inches in length, with a wingspan ranging from 41.3–46.1 inches, and weigh approximately 10.6–24.7 ounces. Observers should note the changes in plumage through the seasons, as juveniles and non-breeding adults will present different markings compared to breeding adults.

Habitat

These gulls favor habitats near bodies of water, such as lakes, rivers, and coastal regions in Canada and the northern United States. They are known to nest colonially on the ground, often on islands, displaying a strong site fidelity year after year.

Distribution

Ring-billed Gulls are commonly found across North America, particularly in American and Canadian parking lots where they gather in large numbers. They are migratory birds, retreating southward to the Gulf of Mexico, the Atlantic and Pacific coasts of North America, and the Great Lakes during the colder months.

Behaviour

The Ring-billed Gull is a sociable bird, often seen in large flocks. It has a reputation for being somewhat of a kleptoparasite, stealing food from other birds, and is also known to scavenge with gusto. These gulls are not shy of human presence and will readily approach areas where food is available.

Song & Calls

The vocalizations of the Ring-billed Gull include a variety of calls that can be heard over the clamor of their flocks, particularly in their communal nesting sites and feeding grounds.

Breeding

These gulls are monogamous during the breeding season and exhibit strong nest site fidelity. They nest in colonies, often returning to the same location annually, though not necessarily with the same mate.

Similar Species

The Ring-billed Gull can be confused with other gull species, but its yellow bill with a black ring, along with its size and leg color, help distinguish it from its relatives.

Diet and Feeding

An omnivorous bird, the Ring-billed Gull's diet is quite varied, including insects, fish, grain, eggs, earthworms, and rodents. They are opportunistic feeders, often seen foraging in flight or picking up food while swimming, walking, or wading. They have adapted well to human environments, where they can be seen taking advantage of discarded or unattended food.

Conservation status

Once hunted for their plumage in the late 19th century, the Ring-billed Gull has since made a remarkable recovery. It is now considered the most common gull in North America, with an estimated population of 2.55 million birds as of 2006, and is listed as Least Concern by the IUCN.