Razorbill vs Common Guillemot

The Razorbill and Common Guillemot are both members of the Alcidae family, but they can be distinguished by their bill shape and plumage patterns. The Razorbill has a thick, blunt bill with a distinct white line, while the Common Guillemot's bill is longer and more slender. Both species have similar dark upperparts and white underparts, but the Razorbill's white line on the bill is a key distinguishing feature.

1. Bill Shape: Look for the Razorbill's thick, blunt bill with a white line. The Common Guillemot has a longer, more slender bill. 2. Plumage: Check for the Razorbill's white line on the bill and the absence of a 'bridle' around the eye. 3. Behavior and Habitat: Observe their proximity to shore and preference for sheltered waters. 4. Vocalization: Listen for the Razorbill's lower-pitched calls if audible.

Both species are similar in size, but the Razorbill is slightly more robust with a thicker neck.

The Razorbill has a black head and back with a sharp contrast to its white underparts. The Common Guillemot also has dark upperparts and white underparts, but lacks the Razorbill's white line on the bill. In breeding plumage, the Common Guillemot may show a faint white 'bridle' around the eye, which the Razorbill does not have.

Both species are often seen swimming and diving for fish, but the Razorbill may be observed closer to shore, especially during the breeding season.

Both species inhabit coastal waters and are often found on rocky cliffs during the breeding season. The Razorbill tends to prefer slightly more sheltered waters compared to the Common Guillemot.

Vocalizations are not the most reliable distinguishing feature, but the Razorbill's calls are generally described as lower-pitched and more guttural compared to the Common Guillemot's higher-pitched calls.