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Ring-billed Gull

Chao Wu
Nov 14, 2015
3 min read

Ubiquitous in nature and disposition, the Ring-billed Gull (Larus delawarensis) is certainly a common sight across a large majority of North America.

Description

Ring-billed Gulls are considered “medium” sized gulls, which are generally smaller in size than some of the Larus gulls it is sympatric (found together) with across its vast range. Adults in breeding plumage have a light grey mantle (back) with black wingtips (which themselves are tipped with white). The key identifying trait is a “ring” of blackish color on the tips of their beaks, hence their common name. Breeding adults also have striking yellow bills, olive-yellow legs and reddish eye-rings. When the breeding season ends, adults often lose some of vibrant coloration and instead becomes a more modest grey-white. In addition, non-breeding individuals also have generally duller yellow coloration on their bills and legs along with faint-grey streaks on their heads and neck. Juveniles are much more difficult to distinguish from other closely related species with their mottled brown and dark eyes. Adults average about 43cm (19in) in length and reach an approximately 124cm (49in) wingspan.

Adult:

Juvenile:

Behavior and Lifestyle

This is probably the best example as to why the use of the word “seagull” is more or less a fallacy. Ring-billed Gulls actually breed within many parts of the mainland, often centered around large sources of open water. Breeding occurs across much of Southern Canada, the Great Lakes, as well as Northern parts of New England in the East. In the West, the birds are often year-round residents of inland areas across patches of Oregon, Washington and Idaho. However, for the large majority of residents, the Ring-billed Gull is often a winter “specialty.” Though, for many individuals, even birders, the word “specialty” is probably too significant. Hundreds to thousands often gather in various reservoirs and lakes across the Atlantic and Pacific seaboards, the American Southeast and even as far Inland as Kansas and Colorado. Some individuals also stray farther South across the border into Mexican waters. Ironically, many Ring-billed Gulls never even set foot into saltwater. For many researchers and scientists, this is said to be the most common and widespread gull in North America.

It is also during the winter months that Ring-billed Gull becomes prominent not just around inland lakes, but also garbage dumps and shopping mall parking lots. They are omnivores which feed on a wide variety of materials and diet varies across location and habitat. Insects, fish, grains are often common foods. In more urbanized areas, Ring-billed Gulls often feed on human refuse and whatever leftover food particles are available. In locations far away from any Ocean, it often is the Ring-billed Gull that one would find scavenging from urbanized areas. While the Ring-billed would not hesitate to steal your bag of fries, it also is a generalist predator which feeds on more conventional prey items. Near bodies of water, these gulls would capture fish and other aquatic organisms. Or, as an alternative, pirate them from other bird species. Interestingly, due to their adaptability to urbanization, the expansion in Ring-billed Gull numbers might harm less aggressive bird species.

Hunting in the Ocean:

Waiting for Handouts:

Population

Today, the Ring-billed Gull continues to expand its population (estimates over two decades ago suggest a size of about 3-4 million...probably much more now). However, during the 19th Century, this species was significantly depleted due to persecution. With better judgment along with the implementation of the Migratory Bird Treaty Act which protects native avian species, the Ring-billed Gull has made a significant comeback.

Similar Species

Herring Gulls are generally the species often confused with Ring-billed Gulls. However, they are significantly larger with a larger, more heavyset bill. In the West, California Gulls are similar to Ring-billed Gulls. However, the former has two spots (one red one black) on the bill versus the single black ring on the latter.

Range Map