Arnoux's beaked whale - Berardius arnuxii

Taxonomy & Nomenclature

Scientific Name Berardius arnuxii
Author Duvernoy, 1851
Taxonomic Rank Species
Taxonomic # 180495
Common Names English: Arnoux's Beaked Whale
Current Standing valid
Taxonomic Parents Kingdom: Animalia
  Phylum: Chordata
    Subphylum: Vertebrata
      Class: Mammalia
        Subclass: Theria
          Infraclass: Eutheria
            Order: Cetacea
              Suborder: Odontoceti
                Family: Hyperoodontidae
                  Genus: Berardius
Taxonomic Children
Synonyms (since 1950)

Taxonomic data is courtesy of the Integrated Taxonomic Information System (ITIS)
See ITIS metadata in XML

Physical Description / Field Identification

Similar in appearance to Baird’s beaked whale, this species has a small head, with a long tube-like beak, moderately steep bulbous forehead, small rounded flippers, short slightly falcate dorsal fin, and (usually) un-notched flukes. A pair of V-shaped throat grooves is present.

Arnoux’s beaked whales are slate gray to light brown; the head region is generally lighter than the rest of the body. The body is often heavily scarred and scratched, and the underside tends to be lighter, and covered with white blotches.

Two pairs of triangular teeth are present at the tip of the lower jaw; they erupt in both sexes and are visible outside the closed mouth. The pair nearest the tip of the jaw is larger.

Arnoux’s beaked whales reach a known maximum size of 9.75 m; females are probably larger than males, as is generally true in beaked whales. Length at birth is unknown, but is probably around 4 m.

Can be Confused With

Arnoux’s beaked whales can be easily confused with southern bottlenose whales, which share much of their range. Differences in head shape, dorsal fin shape, and tooth size and position should be sufficient to distinguish them, if clearly seen. Individuals of some species of Mesoplodon and Indopacetus could also be confused with this species, but they are generally much smaller.


Although this species probably has a circumpolar distribution in deep cold temperate and subpolar waters of the Southern Hemisphere, most records are from the southeast coast of South America, near the Antarctic Peninsula, South Africa, and the Tasman Sea.

Ecology and Behavior

Not much is known of the biology of this species. Most groups number between 6 and 10 individuals, but some as large as 80 whales have been seen. Arnoux’s beaked whales are reportedly shy of boats and can dive for over an hour, making observation difficult.

This species’ reproductive biology is poorly known.

Feeding and Prey

The feeding habits of Arnoux’s beaked whales are assumed to be similar to those of their Northern Hemisphere relatives, Baird’s beaked whales, thus consisting of benthic and pelagic fishes and cephalopods.

Threats and Status

This species has never been hunted to any significant level, and other threats are not known at this point.

Currently, Arnoux’s beaked whales are listed as ‘Lower Risk/Conservation Dependent’ (IUCN) and ‘Not Listed (ESA)’.



Balcomb, K.C. 1989. Baird’s beaked whale Berardius bairdii Stejneger, 1883 Aroux’s beaked whale Berardius arnuxii Duvernoy, 1851. pp. 261-288 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 4: River dolphins and the larger toothed whales. Academic Press.

Hobson, R.P. and A.R. Martin. 1996. Behaviour and dive times of Arnoux’s beaked whales, Berardius arnuxii, at narrow leads in fast ice. Canadian Journal of Zoology 74:388-393.

Kasuya, T. 2002. Giant beaked whales Berardius baridii and B. arnuxii. pp. 519-522 in W.F. Perrin, B. Würsig and J.G. M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.

ITIS TSN180495
Status - ESA, U.S. FWS
Status - Red List, IUCN
    LC (Global)
#records (spatial)52
#records (non-spatial)0
Year1975 - 2024
Latitude-77.86 - -32.67
Longitude-179.37 - 177.94
See metadata in static HTML