Rhinoceros Auklet vs Marbled Murrelet

In short

The Rhinoceros Auklet and Marbled Murrelet are both members of the alcid family, but they differ significantly in appearance and behavior. The Rhinoceros Auklet is notable for its prominent 'horn' above the bill during breeding season, while the Marbled Murrelet is smaller and lacks this feature. Their habitats also differ, with the auklet favoring open waters and the murrelet nesting in coastal forests.

Identification tips

• Look for the 'horn': The Rhinoceros Auklet's 'horn' above the bill is a key breeding season feature.
• Size and shape: The Rhinoceros Auklet is larger and more robust; the Marbled Murrelet is smaller and more compact.
• Plumage patterns: Marbled Murrelets have a marbled appearance, especially outside the breeding season.
• Habitat context: Consider the environment—auklets are more marine, while murrelets are associated with coastal forests.

Size

The Rhinoceros Auklet is larger and more robust compared to the smaller, more compact Marbled Murrelet.

Plumage

The Rhinoceros Auklet has a distinctive 'horn' above the bill in breeding plumage, which the Marbled Murrelet lacks. The murrelet has a marbled brown and white plumage, especially in non-breeding season, while the auklet is generally darker.

Behaviour

Rhinoceros Auklets are mainly nocturnal at breeding colonies and carry fish externally. Marbled Murrelets are elusive, often seen alone or in pairs, and are known for their secretive nesting habits in trees.

Habitat

Rhinoceros Auklets are found in temperate waters of the North Pacific, often near breeding islands. Marbled Murrelets nest in coastal, older forests and are affected by logging and coastal development.

Voice

Vocalizations are not well-documented in the sources, but Marbled Murrelets are known for their high-pitched calls, often heard in forested nesting areas.