Caspian Gull vs Glaucous Gull

The Caspian Gull and Glaucous Gull are large gulls that can be distinguished by their size, plumage, and bill structure. Caspian Gulls are generally smaller with a more slender bill, while Glaucous Gulls are bulkier with a thicker bill and lack black markings on their wingtips. Both species have similar habitats but differ in vocalizations and behavior.

1. Bill Structure: Caspian Gulls have a more slender bill with a pronounced gonys angle, while Glaucous Gulls have a thicker, more robust bill. 2. Wing Markings: Look for black markings on the wingtips of Caspian Gulls, absent in Glaucous Gulls. 3. Size and Bulk: Observe the overall size and bulk; Glaucous Gulls are larger and bulkier. 4. Plumage Tone: Note the paler plumage of the Glaucous Gull, especially in the wingtips. 5. Habitat and Range: Consider the location; Glaucous Gulls are more likely in northern, colder regions.

Caspian Gull is smaller and more slender compared to the larger, bulkier Glaucous Gull.

Caspian Gulls have black markings on their wingtips, while Glaucous Gulls have entirely white wingtips. The Glaucous Gull also tends to have a paler overall appearance.

Both species are opportunistic feeders, but the Glaucous Gull is more likely to be seen scavenging and pirating food from other birds.

Both species can be found in coastal areas, but the Glaucous Gull is more commonly associated with Arctic and sub-Arctic regions, whereas the Caspian Gull is more widespread across Europe and Asia.

Caspian Gulls have a more varied and complex call compared to the simpler, harsher calls of the Glaucous Gull.