- Common Name:
- Ring-Billed Gull
- Scientific Name:
- Larus delawarensis
- Length: 17 to 20 inches; wingspan: 44.5 to 49 inches
- IUCN Red List Status:
- Least concern
- Current Population Trend:
This is the common and familiar “seagull” across much of North America—from coastal beaches to malls in the middle of the continent—yet it is rarely seen offshore. This notably adaptable and bold feeder takes bread from children, soars to catch insects, scavenges at dumps, and even plucks berries from trees. Monotypic. Length 17–20"; wingspan 44.5–49".
Medium-size, 3-cycle gull with sloping head, medium-size bill. On adult, note yellow legs, pale eyes, and neat “ring bill.” Breeding adult: pale gray upperparts; black wing tip with white mirrors on outer 1–2 primaries. Staring pale-yellow eyes set off by red orbital ring; yellow legs and bill; bill with a clean-cut black subterminal ring. Winter adult: head and neck with fine dusky streaking and spotting. Slightly duller bill and legs; dark orbital ring. Juvenile and first-winter: fresh juvenile has neat, scaly upperparts; back usually becomes pale gray by late fall. White head and underparts with coarse dark spots and chevrons, variably lost over winter by molt and bleaching; underwings mostly white. White uppertail coverts with sparse dark bars. Tail variable: base whitish (bleaching to white); broad blackish distal band; often dark wash basally (most heavily marked birds look dark-tailed); tail band sometimes broken subterminally by whitish marks. Dark brown eyes, flesh-pink bill with dark tip, flesh-pink legs. Second-winter: resembles winter adult, but has more black (less white) on wing tips (wing tips at rest usually all black); tail sometimes has black markings (but often all white), head and neck more heavily marked dusky. Legs and bill flesh to yellowish; bill with broad black tip or ring; eyes pale to dark.
The ring-billed is distinctive, but variable, and should be learned well as a reference point for less common species. The larger California (commonly occurs alongside the ring-billed in the west) is a 4-cycle gull with a stouter bill and dark eyes in all ages. The adult California has slightly darker medium gray upperparts (white scapular and tertial crescents contrast, unlike the ring-billed); a red gonys spot as well as a black bill band. Legs often duller and more greenish in winter. The California has relatively longer and narrower wings, which from above have a larger and blunter-based black wing-tip area and larger white mirrors; in flight from below, slightly darker tone of the California’s upperparts apparent as a dusky-gray subterminal secondary band that offsets white trailing edge (underwings more evenly white on the ring-billed). The first-year California is brownish overall, unlike the ring-billed; but the second-winter California is similar to the first-winter ring-billed: In addition to noting size and structure, note the California’s medium gray back; dark brownish greater coverts (pale gray on the ring-billed); and paler legs, often with a greenish hue. The second-winter Herring can also suggest a first-winter ring-billed, but is much larger (not always easy to judge on lone birds) with stouter bill, dark brownish greater coverts, more finely peppered whitish tertial markings, more extensively dark tail, and usually messier and browner appearance overall. Also see the smaller Mew Gull.
Mewing calls and laughing series, higher pitched and less crowing than the California gull’s.
Status and Distribution
Midlatitude North America, winters to Middle America. Breeding: common and usually colonial, on low, sparsely vegetated islands in lakes. Arrives late March–May, departs July–August Dispersal: postbreeding dispersal begins by late June, with juveniles recorded by mid-July as far south as Salton Sea, California. Casual north to central Alaska, accidental Arctic coast of Alaska. Migration: nearly throughout North America where common to abundant in many regions. Mainly August–October. and March–mid-May. Oversummering nonbreeders regular along Pacific, Atlantic, and Gulf coasts, local elsewhere. Winter: Main arrival in most of United States September–October, with most departing February–April. Rarely north to Newfoundland, casually to south-coastal Alaska. Vagrant: casual Europe, West Africa, Hawaii; accidental to Amazonian Brazil.
Largely disappeared from the Great Lakes region and other areas during late 1800s due to human persecution. Recolonization occurred by 1920s, and populations in the Great Lakes/St. Lawrence River region exploded during 1960s and 1970s. Range still expanding in many areas, and today the ring-billed may be the most populous gull in North America, with an estimated 3 to 4 million individuals (70 percent nesting in Canada).