Mesoplodon densirostris

(de Blainville, 1817) - Blainville's beaked whale

Distinctive Characteristics

Adult Blainville's beaked whales are blue-grey above and white below; coloration of young has not been properly described. The dark areas tend to have round or oval white scars and scratches.

The lower skull jaw of this species is highly arched; a massive flattened tusk erupts from the top of this arch in adult males, and it extends above the top of the upper jaw. In some individuals the tusks are covered by a tassel of barnacles.

Can be confused with

Generally, only adult males of this species will be distinguishable from other species of Mesoplodon. The high arching mouthline and massive flattened tusks that extend above the upper jaw will allow identification of bulls.


Maximum size for both sexes appears to be around 4.7 m. Weights of up to 1033 kg have been recorded. Length at birth is presumed to be between 2 and 2.5 m.

Geographical Distribution

Blainville's beaked whales occur in temperate and tropical waters of all oceans. Like other beaked whales, they are found mostly offshore in deep waters.

Biology and Behaviour

Groups of 3 to 7 individuals have been recorded, although singles or pairs are most common. Dives of over 45 minutes have been recorded. Squid are probably the main food items, but some fish may be taken as well.


Some whales of this species have been taken in the North Pacific by Taiwanese whalers, and accidentally by Japanese tuna fishermen in the Indian Ocean.

IUCN Status

Insufficiently known.