Cuvier’s beaked whales are relatively robust, as beaked whales go. They have a short, poorly-defined beak, a sloping forehead, and a mouthline that is upcurved at the rear. A pair of V-shaped throat grooves is present. A diagnostic feature is the slight concavity on the top of the head, which increases in detectability in older animals. A fluke notch is only sometimes present. The dorsal fin is small and falcate, and is set about two-thirds of the way back from the snout tip.
The body is dark gray to light rusty brown, with lighter areas around the head and belly. The head and much of the back of adult males can be completely white. Generally, adults are covered with light scratches and circular marks.
There is a single pair of forward-pointing conical teeth at the tip of the lower jaw; they generally erupt only in adult males and are exposed outside the closed mouth in large bulls.
Length at birth is about 2.7 m; adults reach 7.5 m (males) and 7 m (females). Maximum recorded weight is nearly 3000 kg.
Can be Confused With
This species is most likely to be confused with other beaked whales, especially species of Mesoplodon. The robust body, blunt head, and lighter coloration (especially around the head, and in adult males) may be sufficient to distinguish Cuvier’s beaked whales, if visible. Whales of the genera Hyperoodon and Berardius are larger and have more bulbous foreheads and long tube-like snouts.
Cuvier’s beaked whales are widely distributed in offshore waters of all oceans, from the topics to the polarregions in both hemispheres. They probably have the most extensive range of any beaked whale species.
Ecology and Behavior
This species is the most cosmopolitan of the beaked whales, and is fairly common in certain areas, such as the eastern tropical Pacific. Dives of up to 40 minutes have been documented. Cuvier’s beaked whales are found mostly in small groups of 2-7, but are not uncommonly seen alone.
Seasonality of calving is not known in this species. In general, Cuvier’s life history is very poorly-known.
Feeding and Prey
Cuvier’s beaked whales, like all beaked whales, appear to prefer deep water. Although few stomach contents have been examined, they appear to feed mostly on deep-sea squid, but also take fish and some crustaceans.
Threats and Status
Never the main target of commercial whalers, Cuvier’s beaked whales have sometimes been taken in other fisheries. A few (3-35 per year) were taken in past years in the Baird’s beaked whale fishery off the coast of Japan. The only other threat that is known is the apparent mass strandings of Cuvier’s beaked whales that have resulted from Naval sonar tests, such as those occurring recently in the Bahamas, Caribbean, and the Mediterranean.
Currently, Cuver’s beaked whales are listed as ‘Data Deficient’ (IUCN) and ‘Not Listed (ESA)’.
Heyning, J.E. 1989. Cuvier’s beaked whale Ziphius cavirostris G. Cuvier, 1823. pp. 289-308 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 4: River dolphins and the larger toothed whales. Academic Press.
Heyning, J.E. 2002. Cuvier’s beaked whale Ziphius cavirostris. pp. 305-307 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
Houston, J. 1991. Status of Cuvier’s beaked whale, Ziphius cavirostris, in Canada. Canadian Field-Naturalist 105:215-218.