Cuvier's Beaked Whale (Ziphius cavirostris)

Cuvier's beaked whale
(Ziphius cavirostris)
Photo: NMFS Southwest Fisheries Science Center

Did You Know?

· Cuvier's beaked whales are one of the most frequently sighted species of beaked whales in the world.

· Like other beaked whales, Cuvier's beaked whales are skittish and will avoid ships, including research vessels.

· Of all beaked whale species, Cuvier's beaked whale probably has the most extensive range and distribution.

· Cuvier's beaked whales are the most commonly stranded beaked whale along the U.S. Atlantic coast.

Status
MMPA - Cuvier's beaked whales, like all marine mammals, are protected under the MMPA.

Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ziphiidae
Genus: Ziphius
Species: cavirostris

Species Description
Cuvier's beaked whales, sometimes called "goose-beaked whales," are members of the beaked whale family (Ziphiidae). They can reach lengths of about 15-23 ft (4.7-7 m) and weigh 4,000-6,800 lbs (1,845-3,090 kg). There is no significant "sexual dimorphism" in regards to body size for this species. These medium-size whales have a round and robust body, with a triangular "falcate" dorsal fin located far down the animal's back. The head is a sloping concave-shape with no obvious "melon", an indistinct beak, and a large slit-like blowhole. The jaw-line is slightly upturned giving the whale a "smiling" appearance. The profile of the head is sometimes described as goose-like. Like other beaked whale species, males have two small cone-shaped teeth erupting out of the tip of the bottom jaw that are often used for fighting.

A Cuvier's beaked whale's body has variable coloration that ranges from dark gray to a reddish-brown, with a paler counter-shaded underside. The reddish-brown coloration is caused by the infestation of microscopic "diatoms" and algae. The body is often covered with linear scratches and oval-shaped scars. As this species grows older, they become paler, develop a more significant indentation on the top of the head and accumulate more scarring (especially males). There is a whitish coloration on the face and dark-colored patch around the eye.

Many species of beaked whales (especially those in the genus Mesoplodon) are very difficult to distinguish from one another (even when dead). At sea, they are challenging to observe and identify to the species level due to their cryptic, skittish behavior, a low profile, and a small, inconspicuous blow at the waters surface; therefore, much of the available characterization for beaked whales is to genus level only. Uncertainty regarding species identification of beaked whales often exists because of a lack of easily discernable or distinct physical characteristics.

When at the surface, Cuvier's beaked whales rarely breach or display other active behavior. Their small blow is about 3 ft (1 m) tall, angled slightly forward and to the left, and occurs in 20-30 second intervals, often making it barely visible to observers. As they swim, their head and body will roll high out of the water. When preparing for a deep, vertical dive, they may arch their back more than normal and usually display their flukes. These whales are typically found individually or in small groups from 2-12 animals, but groups of up to 25 animals have been reported. Lone animals are most likely males.

Like other beaked whales, they are deep divers. Cuvier's beaked whales are capable of diving up to at least 3,300 ft (1,000 m) for 20-40 minutes to opportunistically feed on mostly cephalopods (e.g., squid and octopus) and sometimes fish and crustaceans. A pair of ventral throat grooves help to create a vacuum within their mouths, allowing the whales to suck in their targeted prey.

Cuvier's beaked whales reach sexual maturity at lengths of 18-20 ft (5.5-6.1 m) for males and 20 ft (6.1 m) for females, which is usually between 7-11 years of age. Breeding and calving can apparently occur year round, but often during the spring. After a year-long gestation period, females give birth to a single calf every 2-3 years. Newborn calves, dark black or blue in coloration, are about 6.5-9 ft (2-2.7 m) long and weigh 550-660 lbs (250-300 kg). They have an estimated lifespan of up to 60 years.

Habitat
Cuvier's beaked whales can be found in temperate, subtropical, and tropical waters. They have occasionally been sighted in "boreal" waters as well. They prefer deep "pelagic" waters (usually greater than 3,300 ft (1,000 m) of the continental slope and edge, as well as around steep underwater geologic features like banks, seamounts and submarine canyons. Recent surveys suggest that beaked whales, like this species, may favor oceanographic features such as currents, current boundaries, and core ring features.

Cuvier's Beaked Whale Range Map
(click for larger view PDF)

Distribution
Cuvier's beaked whales have a cosmopolitan distribution and can be found in most oceans and seas worldwide. Most of the distribution information is based on stranding records. The seasonality and migration patterns of this species are not known. Recent genetic diversity studies indicate that Cuvier's beaked whales generally remain in their "home" ocean basins, which may create well-defined populations. In the Northern Hemisphere, they are known to occur near the Aleutian Islands, Bay of Biscay, British Columbia, Canada, Gulf of California, Gulf of Mexico, Massachusetts, Mediterranean Sea and the Shetlands. In the Southern Hemisphere, they are known to occur near New Zealand, South Africa, and Tierra del Fuego. They have also stranded in tropical environments such as the Bahamas, Caribbean Sea, Mediterranean Sea and the Galapagos Islands.

Population Trends
For management purposes, Cuvier's beaked whales inhabiting U.S. waters have been divided into five stocks: the Alaska Stock, the California/Oregon/Washington stock, the Hawaiian stock, the Northern Gulf of Mexico stock and the Western North Atlantic stock. Reliable abundance estimates are unavailable for the Alaska stock. The estimated population of the Hawaiian stock is 7,000-13,000, the California/Oregon/Washington stock is 1,100-1,900, and the northern Gulf of Mexico stock is 65-95 animals. In the Western North Atlantic, the abundance estimate for undifferentiated beaked whales, which includes Cuvier's beaked whales, is 2,100-3,500 animals. Beaked whales are often lumped together in stock estimates due to their cryptic nature and difficulty of sighting and identifying them at sea. Estimates do not include a correction factor for submerged animals (with long dive times), which may be substantial and underestimate actual abundance. The Northern Gulf of Mexico and Western North Atlantic stocks are considered "strategic" because of uncertainty regarding stock size and evidence of human induced mortality and serious injury associated with acoustic activities. Other abundance estimates for Cuvier's beaked whales includes 20,000 in the eastern tropical Pacific and 90,000 in the eastern North Pacific. There are insufficient data to determine the population trends for this species.

Threats
Cuvier's beaked whales are subject to entanglement in fishing gear, ship strikes, and possible trauma from acoustic sources. They have also been taken in fisheries in the Caribbean, Chile, Indonesia, Peru and Taiwan. These beaked whales have been taken in Japanese whaling operations (3-35 a year) targeting Baird's beaked whales. This species of beaked whales may be sensitive to underwater sounds and anthropogenic noise. Recently, strandings of this species in the Bahamas, Caribbean Sea, Canary Islands, Gulf of California and Mediterranean Sea have been associated with active sonar and seismic activities. Anthropogenic noise levels in the world's oceans are an increasing habitat concern, particularly for deep-diving cetaceans like Cuvier's beaked whales that use sound to feed, communicate, and navigate in the ocean.

Conservation Efforts
The IUCN Red List of Threatened Species considers Cuvier's beaked whales as "Data Deficient" due to insufficient information on population status and trends.

In 1997, NMFS implemented the Pacific Offshore Cetacean Take Reduction Plan, which requires the use of pingers and 6-fathom net extenders in the CA/OR drift gillnet fishery to reduce bycatch of cetaceans, including Cuvier's beaked whales. The Pacific Offshore Cetacean Take Team continues to meet and recommend measures to further reduce bycatch and achieve MMPA goals.

Regulatory Overview
This species is protected under the Marine Mammal Protection Act of 1972 amended.

Key Documents
(All documents are in PDF format.)

Title	Federal Register	Date
Pacific Offshore Cetacean Take Reduction Plan (POCTRP) Interim Final Rule to Amend Pinger Specifications	64 FR 3431	01/22/1999
POCTRP Final Rule to Require New Training, Equipment, and Gear Modifications for CA/OR Drift Gillnet Fishery	62 FR 51805	10/03/1997
Stock Assessment Reports	n/a	various

More Information

References:

Reeves, R. R., P. A. Folkens, et al. (2002). Guide to Marine Mammals of the World. New York, Alfred A. Knopf. p.254-257.
Jefferson, T. A, M. A. Webber, and R. L. Pitman. (2008). Marine Mammals of the World, A Comprehensive Guide to their Identification. Amsterdam, Elsevier. p. 98-101.
Shirihai, H. and B. Jarrett (2006). Whales, Dolphins and Other Marine Mammals of the World. Princeton, Princeton University Press. p.107-110.