How to identify the Yellow-legged Gull

To correctly identify the Yellow-legged Gull (Larus michahellis), check each of these features. Birds can be tricky: habit, habitat, and call often confirm a sighting that a single photo cannot.

Size at a glance

Length

52-68 cm (20-27 in)

Wingspan

120-155 cm (47-61 in)

Weight

760-1600 g (1.7-3.5 lbs)

Physical features to check

1. 1

   Plumage

   Overall feather coloration and pattern.

   Adults in breeding plumage have a white head, neck, underparts, and tail. The back and upperwings are medium to dark grey. The wingtips are black with prominent white 'mirrors' (spots). Non-breeding adults show fine streaking on the head and nape, which is less extensive than in Atlantic Herring Gulls.

2. 2

   Beak shape

   Shape and color of the bill: a key field mark.

   Strong, heavy, and conical, yellow with a prominent red spot (gonys spot) on the lower mandible.

3. 3

   Eye color

   Iris color and any distinctive eye markings.

   Pale yellow, surrounded by a distinct red orbital ring.

4. 4

   Leg color

   Leg and foot color.

   Bright yellow, becoming duller, more yellowish-orange, or even greyish-yellow outside the breeding season, especially in younger adults.

5. 5

   Distinguishing features

   Standout features that separate this species.

   Combination of yellow legs (especially bright in breeding season), red orbital ring, relatively dark grey mantle, and heavy yellow bill with a red spot. Juveniles and immatures are complex and variable but generally feature dark streaking/mottling on a pale ground, dark bills, and dark eyes.

6. 6

   Juvenile appearance

   How young birds differ from adults.

   First-year birds are heavily mottled brown and grey, with a dark bill, dark eyes, and pinkish-grey legs. The rump and tail base are whiter than in first-year Herring Gulls. Second-year birds show an intermediate plumage, with a greyer mantle developing, often a paler bill base, and legs starting to turn yellowish-pink. The plumage develops gradually, becoming more adult-like over 3-4 years.

7. 7

   Seasonal changes

   Plumage variation between breeding and non-breeding seasons.

   Adults show subtle seasonal changes, mainly a slight streaking on the head and nape in non-breeding plumage and a dulling of leg and bill coloration. The red orbital ring is most prominent during the breeding season. Juveniles undergo significant plumage changes over several years before reaching adult plumage.

8. 8

   Sexual dimorphism

   How males and females differ.

   Minimal in plumage or coloration. Males are generally slightly larger and heavier than females, but this difference is not consistently discernible in the field.

Key field marks

• Leg Color. Look for bright, rich yellow legs in adults, especially during the breeding season. Duller yellow or yellowish-orange can occur at other times or in younger adults.
• Mantle Color. Observe the grey saddle (back and upperwings); it's typically a medium to dark grey, darker than Herring Gull but lighter than Lesser Black-backed Gull.
• Bill Characteristics. Identify the heavy yellow bill with a prominent red spot on the lower mandible (gonys spot). The bill often appears proportionally larger and more powerful than a Herring Gull's.
• Red Orbital Ring. A distinct red ring around the eye in adults is a key field mark, especially prominent in breeding birds.
• Head Streaking (Non-breeding). Note the relatively clean white head in non-breeding plumage, with minimal or only fine streaking on the nape and hindneck, less extensive than seen in Herring Gulls.
• Juvenile Plumage. In juveniles, look for a generally paler, washed-out brownish appearance with a whiter rump and tail base compared to the more uniformly dark first-year Herring Gulls. The primaries are often darker, appearing almost black, and the bill dark.

Explore the Yellow-legged Gull