Mesoplodon stejnegeri

True, 1885 - Stejneger's beaked whale

Distinctive Characteristics

Stejneger's beaked whale has the characteristic Mesoplodon body shape. Apparently, both sexes are uniformly grey to black, often with extensive scarring in bulls.

The flattened tusks of males are situated near the middle of the lower jaw, and point forward. They are located on raised prominences, so that the crowns extend above the rostrum.

Can be confused with

Adult males will be distinguishable from most other Mesoplodon species by tooth shape and position. Within Stejneger's beaked whale's range, both Hubbs' and Blainville's beaked whale beaked whale males have similar teeth.


Both sexes reach lengths of at least 5.3 m. Newborns are assumed to be between 2 and 2.5 m in length.

Geographical Distribution

Stejneger's beaked whales are found in continental slope and oceanic waters of the North Pacific Basin, from southern California, north to the Bering Sea, and south to the Sea of Japan. This appears to be primarily a cold temperate and subarctic species. It is most commonly stranded in Alaska, especially along the Aleutian Islands.

Biology and Behaviour

Groups of 5 to 15 individuals have been observed, often containing animals of mixed sizes. Stejneger's beaked whales are known to feed on squid.


Several Stejneger's beaked whales are known to have been taken in salmon driftnets off Japan, and there have probably been occasional direct catches of this species off Japan and possibly elsewhere.

IUCN Status

Insufficiently known.