California Gull vs Iceland Gull

In short

California Gull and Iceland Gull can be distinguished by structural differences and plumage details. California Gull is generally larger with a heavier bill, while Iceland Gull is smaller and more delicate. Plumage differences are subtle but can be key in identification.

Identification tips

• Bill Size: California Gull has a heavier, more robust bill compared to the slender bill of Iceland Gull.
• Wing Tips: Look for black wingtips with white spots on California Gull; Iceland Gull lacks these black markings.
• Mantle Color: California Gull's mantle is darker than the pale grey of Iceland Gull.
• Seasonal Variation: Be aware of seasonal plumage changes, especially in Iceland Gull, which can vary widely.
• Location: Consider the habitat; Iceland Gulls are more likely in coastal areas, especially in winter.

Size

California Gull is larger and bulkier compared to the smaller, more delicate Iceland Gull.

Plumage

California Gull has a darker mantle and more pronounced black wingtips with white spots, whereas Iceland Gull has a paler mantle and lacks black wingtips, showing more uniform pale grey or white primaries.

Behaviour

Both species exhibit similar gull behaviors, often seen foraging in flocks or resting in groups. No significant behavioral differences are noted.

Habitat

California Gull is often found in coastal and inland habitats including lakes and rivers, while Iceland Gull is more associated with coastal regions and often nests on rocky cliffs.

Voice

Both species have typical gull calls, but specific vocal differences are not well-documented.