Short-billed Gull
Larus brachyrhynchus
The Short-billed Gull, formerly known as Mew Gull in North America (the name "Mew Gull" now generally refers to European forms of *Larus canus*), is a graceful, medium-sized gull that is a common sight in Oregon, especially along the coast, in estuaries, and on larger inland bodies of water during migration and in winter.
Overall Characteristics of Short-billed Gulls:
Size & Build: It's a relatively small, "petite" or "dainty" gull, larger than a Bonaparte's Gull but smaller than a Ring-billed Gull. It has a round head, a short neck, and a relatively small, slender bill, giving it a "gentle" or "dove-like" expression. Its wings are moderately long, extending beyond the tail when at rest.
Bill: Entirely yellow in breeding adults, but can be duller, greenish-yellow, or even have a faint dusky band in non-breeding plumage and immatures. It is notably *without* a prominent black ring like a Ring-billed Gull.
Legs: Yellow in adults.
Flight: Buoyant and graceful, often seen flying with soft wingbeats. In flight, the upperwing shows a medium gray back and inner wings, with prominent black wingtips that have distinct white "mirrors" (spots) on the outer primaries. The trailing edge of the wing is white.
Voice: A high, clear, almost cat-like "mew" or "meow," which is how it got its previous common name.
Plumage - Very Similar for Male and Female, but varies by age and season:
1. Breeding (Alternate) Plumage (Adult, seen in Oregon during spring migration, late summer adults):
Head: Pure white head and neck.
Body: Pale to medium gray back and upperwings, bright white underparts.
Bill: Entirely yellow, with no markings.
Legs: Yellow.
Eyes: Dark, with a thin reddish orbital ring (eye-ring).
2. Non-breeding (Basic) Plumage (Adult, most common in Oregon from late summer through winter):
Head: Head and neck are white, but with varying amounts of **smudgy brownish-gray mottling** on the crown, nape, and around the eye/ear area. The extent of this mottling can vary individually.
Body: Pale to medium gray back and upperwings, white underparts, similar to breeding plumage.
Bill: Duller yellowish or greenish-yellow, often with a faint dusky or dark smudge/ring near the tip.
Legs: Pinkish-yellow to yellowish.
Eyes: Dark, with a grayish orbital ring.
3. First-Winter Plumage (Immature, very common in Oregon during fall and winter):
Overall: This plumage is a mix of brownish, gray, and white, with a more "messy" appearance than adults.
Upperparts: Back often has a mixture of gray feathers (newer adult-like feathers) and brownish, mottled juvenile feathers, often appearing quite dark and smudgy.
Wings: Darker than adults, with a prominent dark brown or blackish "carpal bar" (a diagonal band across the wing at the wrist joint) on the upperwing. The wingtips are blackish.
Tail: Has a distinct **black band** at the tip of the tail, contrasting with a white base.
Underparts: White, but often with some dusky mottling or streaking on the breast and flanks.
Bill: Pinkish at the base with a sharp black tip.
Legs: Pinkish.
Short-billed Gulls take three years to attain full adult breeding plumage, so you may also see second-winter birds which show intermediate plumages.
Distinguishing Male from Female:
As with many gulls, **male and female Short-billed Gulls have virtually identical plumage**. There are no specific feather patterns or colors that reliably differentiate the sexes in the field.
However, there can be very subtle structural differences:
Males** average **slightly larger** than females. This can include a slightly larger head, and a marginally thicker bill.
These differences are typically **not discernible** when observing a single bird. They are most apparent when comparing a known breeding pair standing side-by-side, where the male will usually appear marginally more robust. For general field identification in Oregon, these subtle differences are not practical for sexing.
Therefore, when identifying Short-billed Gulls in Oregon, you will primarily rely on the combination of size, bill shape and color, leg color, flight pattern (especially the white wingtip mirrors), and the specific plumage characteristics for their age and season.
Overall Characteristics of Short-billed Gulls:
Size & Build: It's a relatively small, "petite" or "dainty" gull, larger than a Bonaparte's Gull but smaller than a Ring-billed Gull. It has a round head, a short neck, and a relatively small, slender bill, giving it a "gentle" or "dove-like" expression. Its wings are moderately long, extending beyond the tail when at rest.
Bill: Entirely yellow in breeding adults, but can be duller, greenish-yellow, or even have a faint dusky band in non-breeding plumage and immatures. It is notably *without* a prominent black ring like a Ring-billed Gull.
Legs: Yellow in adults.
Flight: Buoyant and graceful, often seen flying with soft wingbeats. In flight, the upperwing shows a medium gray back and inner wings, with prominent black wingtips that have distinct white "mirrors" (spots) on the outer primaries. The trailing edge of the wing is white.
Voice: A high, clear, almost cat-like "mew" or "meow," which is how it got its previous common name.
Plumage - Very Similar for Male and Female, but varies by age and season:
1. Breeding (Alternate) Plumage (Adult, seen in Oregon during spring migration, late summer adults):
Head: Pure white head and neck.
Body: Pale to medium gray back and upperwings, bright white underparts.
Bill: Entirely yellow, with no markings.
Legs: Yellow.
Eyes: Dark, with a thin reddish orbital ring (eye-ring).
2. Non-breeding (Basic) Plumage (Adult, most common in Oregon from late summer through winter):
Head: Head and neck are white, but with varying amounts of **smudgy brownish-gray mottling** on the crown, nape, and around the eye/ear area. The extent of this mottling can vary individually.
Body: Pale to medium gray back and upperwings, white underparts, similar to breeding plumage.
Bill: Duller yellowish or greenish-yellow, often with a faint dusky or dark smudge/ring near the tip.
Legs: Pinkish-yellow to yellowish.
Eyes: Dark, with a grayish orbital ring.
3. First-Winter Plumage (Immature, very common in Oregon during fall and winter):
Overall: This plumage is a mix of brownish, gray, and white, with a more "messy" appearance than adults.
Upperparts: Back often has a mixture of gray feathers (newer adult-like feathers) and brownish, mottled juvenile feathers, often appearing quite dark and smudgy.
Wings: Darker than adults, with a prominent dark brown or blackish "carpal bar" (a diagonal band across the wing at the wrist joint) on the upperwing. The wingtips are blackish.
Tail: Has a distinct **black band** at the tip of the tail, contrasting with a white base.
Underparts: White, but often with some dusky mottling or streaking on the breast and flanks.
Bill: Pinkish at the base with a sharp black tip.
Legs: Pinkish.
Short-billed Gulls take three years to attain full adult breeding plumage, so you may also see second-winter birds which show intermediate plumages.
Distinguishing Male from Female:
As with many gulls, **male and female Short-billed Gulls have virtually identical plumage**. There are no specific feather patterns or colors that reliably differentiate the sexes in the field.
However, there can be very subtle structural differences:
Males** average **slightly larger** than females. This can include a slightly larger head, and a marginally thicker bill.
These differences are typically **not discernible** when observing a single bird. They are most apparent when comparing a known breeding pair standing side-by-side, where the male will usually appear marginally more robust. For general field identification in Oregon, these subtle differences are not practical for sexing.
Therefore, when identifying Short-billed Gulls in Oregon, you will primarily rely on the combination of size, bill shape and color, leg color, flight pattern (especially the white wingtip mirrors), and the specific plumage characteristics for their age and season.