Great Cormorant vs European Shag

In short

The Great Cormorant and European Shag are both large, dark waterbirds, but the Great Cormorant is bulkier with a thicker neck and a more robust bill. The European Shag is more slender with a distinctive greenish sheen to its plumage and a thinner, more hooked bill.

Identification tips

1. Size and Structure: Look for the larger size and thicker neck of the Great Cormorant. 2. Bill Shape: The Great Cormorant has a more robust bill, while the European Shag's bill is thinner and more hooked. 3. Plumage: In breeding season, check for the white throat patch on the Great Cormorant; the European Shag has a greenish sheen. 4. Habitat: Note the habitat; European Shags are more likely to be seen in strictly coastal areas.

Size

The Great Cormorant is larger and bulkier than the European Shag.

Plumage

The Great Cormorant has a more uniform dark plumage with a white patch on the throat during the breeding season, while the European Shag has a glossy greenish sheen and lacks the white throat patch.

Behaviour

Both species dive for fish, but the Great Cormorant often forages in flocks, especially in areas with schooling fish. The European Shag tends to be more solitary or in smaller groups.

Habitat

Great Cormorants are more adaptable, found in both inland and coastal waters, whereas European Shags are more strictly coastal.

Voice

Vocalizations are not a primary distinguishing feature in the field; both species are generally quiet, with guttural calls.