Family Auks (Alcidae)


Japanese Murrelet (Synthliboramphus wumizusume)


French: Guillemot du Japon German: Japanalk Spanish: Mérgulo japonés
Other common names: Crested Murrelet

Uria wumizusume


, 1836,



Closely related to S. antiquus. Monotypic.


Coasts and islands off E & S Japan (mainly from S Honshu and Izu Is S to Shikoku and Kyushu) and S Korea; possible breeding in Russia (Peter the Great Bay). Winters mostly offshore from breeding locations.

Descriptive notes

24–26 cm; 139–213 g. Short, thick, pale bluish-grey bill with dark culmen; iris dark brown, almost blackish; black head with crest of long, narrow black feathers... read more


Two calls described, a "byubyubuy" nocturnally at colonies, and a bunting-like "chi... read more


Offshore and along sea coasts in boreo-cool subtropical waters of NW Pacific. Breeds on small rocky... read more

Food and feeding

Mostly planktonic crustaceans, especially euphausiids, and small larval fish throughout year. Summer foods probably similar to those of... read more


Phenology and reproductive biology poorly known. Spring arrival mid to late Feb; laying normally mid Mar to late Jun or early Jul, and... read more


Winters mainly offshore, mostly close to breeding areas. General post-breeding dispersal normally... read more

Status and conservation

VULNERABLE. Rarest and most threatened alcid, and probably second-most threatened seabird species in N Hemisphere. Population small and still declining, estimated by BirdLife... read more

Recommended citation

Nettleship, D.N. & Kirwan, G.M. (2020). Japanese Murrelet (Synthliboramphus wumizusume). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 3 April 2020).