Beaked Whales
 

Common Name: Beaked Whales

Class: Mammalia

Order: Cetacea

Family: Ziphiidae

Genus: Six genera

Species: 19 species

 

Blainville's beaked whale, Mesoplodon densirostris

Beaked Whales: Family Ziphiidae

The whales of the family Ziphiidae belong to the Mammalian Order Cetacea, in the suborder Odontoceti.  All toothed whales belong to the suborder Odontoceti, which is Latin for "toothed whales".  Ziphiidae is Latin, derived from the Greek xiphos, meaning "sword".  This refers to the prominent beaks of these animals.

Blainville's beaked whale, Mesoplodon densirostris

Ziphiidae is the second largest cetacean family, after Delphinidae.  Members of this family are characterized by a prominent beak, sometimes with a bulging forehead.  Two visible teeth protruding from the lower jaw are evident in most species.  Other non-functional teeth are present in some species, with the exception of Shepherd's beaked whale, which has small functional teeth.  All species lack upper teeth, with the exception of Gray's beaked whale and Shepherd's beaked whale.  Heavy scarring suggests the large teeth of the lower jaw are used aggressively.  Very little data has been collected on these animals, with some species actually never having been observed alive.  Beaked whales feed on deep ocean fish and cephalopods, diving to extremely deep depths to hunt for their prey.  Adaptations for deep diving include small dorsal fins, sound receiving channels and tunnels present in the upper beak to receive sound, and recesses in the body walls acting as "flipper pockets" which reduce the drag of pectoral fins.  The flukes of beaked whales also differ from other cetaceans, lacking a central notch.  The tendency of beaked whales to dive deeply frequently prevents researchers from adequately studying their behavior.

Blainville's beaked whale, Mesoplodon densirostris

The general difficulty of studying these animals has prevented any reliable population estimates.  Due to the overall lack of sightings, it is assumed that most species are quite rare.  Strandings of unknown causes have been the main sources of descriptive data for most species.  The northern bottlenose whale was once hunted for the spermaceti oil found in its melon, but has been protected since 1973.  A possible threat to beaked whales is the use of low frequency sonar used by the United States Navy.  Further studies are needed to confirm its affect on ziphiids, as well as other cetacean species.

There are six genera within the family Ziphiidae, containing a total of 19 species.  The genera and species are:

Genus:  Ziphius

The generic name Ziphius, is Latin, derived from the Greek xiphos, meaning "sword".  This refers to the beak of this animal.

 

Cuvier's beaked whale Ziphius cavirostris

The specific name, cavirostris, is derived from the Latin words cavus, meaning "hollow", and rostrum, meaning "snout".  This refers to the hollow formation at the base of this species' snout.  The common name is named for Baron Georges Cuvier (1769-1832), a French naturalist and comparative anatomist.  This species inhabits temperate and tropical ocean waters worldwide.  The whales seem to move north to temperate waters during the summer.  Sightings have occurred as far north as Alaska. Two large teeth are present in males.  These teeth are not visible in females.  Adults are grayish in color, occasionally with darker dorsal coloration and white splotches on the head and back.  Length at maturity is about 20ft.  Some data suggests adults weigh between 2.5-3 tons.  Females are generally larger than males.  A distinct calving season has not been concluded.  Gestation lasts about 12 months.  Calves are 6-9ft in length.  Lifespan estimates range from 36-62 years.

 

 

 

Genus:  Hyperoodon

The generic name Hyperoodon, is derived from the Greek words hyperoe, meaning "the upper mouth or palate", and odontos, meaning "tooth".  However, this name is misleading, considering whales of this genus have only two teeth on their lower jaw.  In 1788, a French zoologist, Count de Lacepede (1756-1825), misidentified small bumps on the palate of stranded beaked whale as teeth, giving rise to this name.  The two species belonging to this genus are similar in physical size and coloration.  Adult males reach lengths of about 30 feet, while females grow to about 25 feet in length.  Young males and females do not have the very prominent bulging forehead, which contains a large oil filled organ similar to the spermaceti organ found in sperm whales.  Males have a pair of protruding teeth on the lower jaw, while both sexes have vestigial teeth in the upper and lower jaws.  Calving seasons for both species appear to peak in the spring.  Gestation lasts about 12 months.  Newborn calves are 9-10ft in length.  Males achieve sexual maturity at 7-11 years, while females sexually mature at 8-12 years.  The estimated lifespan is at least 37 years.

 

Northern bottlenose whale Hyperoodon ampullatus

The specific name, ampullatus, is Latin for "flask or bottle".  This describes the animal's head, which is characterized by narrow snout protruding from a well-defined, large, fleshy melon.  The range of species includes the North Atlantic and occasionally the Mediterranean Sea.

 

Southern bottlenose whale Hyperoodon planifrons

The specific name, planifrons, is derived from the Latin words planitia, meaning "flat", and frons, meaning "forehead".  This refers to the large, flat forehead of this species.  The range of this species includes the southern portions of the Atlantic Ocean, Pacific Ocean, and Indian Ocean, inhabiting the coastal areas of Australia, New Zealand, South Africa, and Antarctica.

 

 

 

Genus:  Tasmacetus

The generic name Tasmacetus, probably means "Tasman whale", referring to the geographic range of this species, which includes the southern Pacific Ocean surrounding Australia, New Zealand, and Tasmania.

 

Shepherd's beaked whale or Tasman whale Tasmacetus shepherdi

The specific name, shepherdi, is named for G. Shepherd, a curator at the Wanganui Alexander Museum in New Zealand.  Shepherd collected a nearly complete skeleton of the animal while at the museum.  Descriptive data of this species is based on four specimens, three males and one female.  It appears the two large teeth of the anterior lower jaw are present only in males, for they had not erupted in the single female specimen.  Shepherd's beaked whale has small functional teeth in addition to the large protruding pair.  Unlike all other beaked whales, with the exception of Gray's beaked whale, Shepherd's beaked whale has teeth on the upper jaw.  The diet of this species includes species of small deep ocean fish and crustaceans.  Adults grow to lengths of 18-21ft.

 

Genus:  Berardius

The generic name Berardius, is named for Auguste Berard, the commander of a French naval station at Banks Peninsula in New Zealand during the.  He was also the captain of the ship responsible for the delivery of the first Arnoux's beaked whale skull of to Georges Louis Duvernoy (1777-1855), a French zoologist and assistant of Georges Cuvier.  Duvernoy examined and named the specimen.  The two species of this genus are not specifically distinct.  They are separated geographically.  Arnoux's beaked whale and Baird's beaked whale are the largest beaked whales species.  Members of this genus have the most symmetrical skulls of all odontocetes.  Two large teeth protrude from the lower jaw of both species.  Deep sea fish, octopus, squid and crustaceans compose their diet.

 

Arnoux's beaked whale Berardius arnuxii

The specific name, arnuxii, is named for M. Arnoux, a French surgeon responsible for presenting a skull of the species to the Paris Museum of Natural History in 1846.  Georges Louis Duvernoy was responsible for naming the skull.  Unfortunately, he misspelled "Arnoux", omitting the "o" from the name.  Arnoux's beaked whale inhabits the ocean waters of the Antarctic pack ice, the South Pacific, southern Indian Ocean, and South Atlantic.  This species is smaller than Baird's beaked whale, generally growing no longer than 30ft in length.

 

Baird's beaked whale Berardius bairdii

The specific name, bairdii, is named for Spencer Fullerton Baird (1823-1887), an American naturalist and secretary at the Smithsonian Institution.  Baird's beaked whale is found in the throughout the northern Pacific, as far north as the Bering Sea and as far south as Baja California.  Adults grow to lengths of 36-40ft, and weigh about 12 tons.  Females are slightly larger than males.  Migrations during the summer and autumn to the continental slope from the open ocean have been recorded.  Mating occurs in late fall, with calving peaking in mid-spring.  The gestation period is the longest of all cetaceans, at about 17 months.  Lifespan estimates range from 54-84 years.

 

 

 

Genus:  Indopacetus

The generic name, Indopacetus, probably means "Indopacific whale", referring to the geographic range of this species.

 

Indo-Pacific beaked whale Indopacetus pacificus

The specific name, pacificus, means "belonging to the Pacific", referring to the Pacific Ocean.  Descriptive data of this species is based on six specimens, none of which were  alive when obtained.  Based on the locations of the specimens, researchers believe this whale's range includes the subtropical waters of the southern Pacific Ocean and Indian Ocean.  No reliable data regarding its physical description, diet, and behavior exists.

 

 

 

Genus:  Mesoplodon

The generic name Mesoplodon, is derived from the Greek words mesos, meaning "middle", oplon, meaning "tool or weapon", and odon, meaning tooth.  Collectively, this means "armed with a tooth in the middle of the jaw", referring to the placement of the teeth in this genera.

 

Sowerby's beaked whale Mesoplodon bidens

The specific name, bidens, is Latin for "two teeth".  This refers to the only two teeth this species has, which are in the middle of the lower jaw.  The common name is named for James Sowerby (1757-1822), an English naturalist and artist, who first to described the whale in 1804.  The primary range of this species includes the temperate waters of the North Atlantic, possibly the Mediterranean Sea and Gulf of Mexico.  Body coloration is bluish gray dorsally, fading to a lighter color ventrally.  Adults grow to a length of about 15 feet.

 

Andrews' beaked whale Mesoplodon bowdoini

The specific name, bowdoini, is named for George Bowdoin, a trustee of the American Museum of Natural History during the early 20th century.  The common name, Andrews', is probably named for Roy Chapman Andrews (1884-1960), a world famous explorer and director of the American Museum of Natural History.  Andrews' was a marine mammalogist, as well as a paleontologist, also discovering the first dinosaur eggs during an expedition to Mongolia.  The range of this species includes the subtropical waters surrounding Australia, New Zealand, and Tasmania.  Body coloration is dark gray, while the head and beak are white.  Males are larger than females, reaching lengths of about 15 feet.  Females generally grow to 12-13ft in length.

 

Hubb's beaked whale Mesoplodon carlhubbsi

The specific name, carlhubbsi, is named after Carl Hubbs (1894-1979), an American ichthyologist and the first to describe the whale.  The range of this species includes the temperate waters of the North Pacific.  Males have small functional teeth in addition to the two prominent large teeth.  Body coloration is dark gray, with white patches on the head.  Adults range in size from 15-20ft in length.

 

Blainville's beaked whale Mesoplodon densirostris

The specific name, densirostris, is derived from the Latin words densus, meaning "dense", and rostrum, meaning "snout".  The upper mouth of this species is composed of the densest bone of all known animals.  The bone has a mass of 2.7 grams per cubic centimeter.  This means it is four times denser than the tympanic bulla of the fin whale, which was previously thought to contain the densest bone, and 50% denser than any other mammalian bone.  Tiny channels throughout the bone make it extremely brittle, which suggests whales of this species do not ram one another.  Some researchers have proposed these tunnels are necessary for receiving acoustical signals used while echolocating.  The common name, Blainville, is named for Henri Marie Ducrotay de Blainville (1777-1850), a French zoologist and anatomist.  Blainville became the chair of anatomy and zoology in the Faculty of Sciences at Paris with the help of Georges Cuvier.  The range of this species includes the tropical and subtropical waters of all oceans.  Color ranges from gray to brown dorsally, with a lighter underside.  Adults range in size from 10-20ft in length.

 

Blainville's beaked whale, Mesoplodon densirostris

 

Gervais' beaked whale Mesoplodon europaeus

The specific name, europaeus, means "belonging to Europe", probably referring to the range of this species.  The common name is named for the Paul Gervais (1816-1879), a French paleontologist and colleague of George Cuvier and Henri Marie Ducrotay de Blainville.  This species' range  includes the temperate and tropical waters of the North Atlantic Ocean.  Body coloration is dark gray dorsally, fading to a lighter shade ventrally.  Adults range in size from 13-17ft in length.

 

Ginkgo-toothed beaked whale Mesoplodon ginkgodens

The specific name, ginkgodens, is derived from the Latin word dens, meaning "tooth", and the word ginkgo, a type of tree.  This refers to the similarity in shape of the ginkgo-toothed beaked whale's tooth and that of a ginkgo tree's leaf.  The range of this species includes the subtropical and tropical waters of the Pacific Ocean and Indian Ocean.  The two protruding teeth of the ginkgo-toothed whale are shaped like leaves of the ginkgo tree.  Body coloration is characterized by a dark gray background with a spattering of white spots.  Adults reach lengths of 14-15ft.

 

Gray's beaked whale Mesoplodon grayi

The specific name, grayi, is named for a former director of the British Museum, John E. Gray (1800-1875).  Gray described at least three species of beaked whale during his career.  He died one year before the naming of this specimen, which occurred in 1876.  The range of this species includes  the temperate and subtropical waters of the southern hemisphere.  Interestingly, one confirmed sighting of this whale in the northern hemisphere, off the coast of the Netherlands, exists.  This species has teeth on the upper jaw, unlike all other beaked whale species, with the exception of Shepherd's beaked whale.  Body coloration is dark gray dorsally, fading to a lighter shade ventrally.  The beak is white in color.  Adults grow to lengths of 18-20ft.

 

Hector's beaked whale Mesoplodon hectori

The specific name, hectori, is named for James Hector (1834-1907), a curator of the Wellington Museum in New Zealand.  Information regarding this species stems from 20 specimens, which were found from southern California, Argentina, the Falkland Islands, South Africa, New Zealand, and Tasmania.  These locations suggest this species' range includes the tropical and subtropical waters of the Pacific Ocean, Indian Ocean, and Atlantic Ocean.  Body coloration is dark gray dorsally, fading to a lighter shade ventrally.  Adults grow to about 13 feet in length.

 

Strap-toothed whale or Layard's beaked whale Mesoplodon layardii

The specific name, layardii, is named for Edgar Leopold Layard (1824-1900), a curator of the South American Museum.  Layard was the first to describe this whale species.  Strap-toothed refers to the shape of the two teeth of the lower jaw, which protrude only from male whales, even while the mouth is closed. In fact, these teeth prevent males from opening their mouths greater than 5-6 inches.  This whale's range includes the subtropical waters of the southern Pacific Ocean and southern Atlantic Ocean.  Body coloration is dark gray dorsally, fading to a lighter shade ventrally.  Light splotches are present on the head and beak.  Adults reach lengths of 15-20ft.

 

True's beaked whale Mesoplodon mirus

The specific name, mirus, is Latin for "wonderful or extraordinary".  This refers to the placement of two teeth at the very tip of the whale's lower jaw.  The common name is named for the F.W. True, an American zoologist and whale researcher of the late 19th century.  This species' range includes the temperate waters of the Atlantic Ocean and Indian Ocean.  Body coloration is gray dorsally, fading to a lighter shade ventrally.  Adults grow to about 15 feet in length.

 

Pygmy beaked whale Mesoplodon peruvianus

The specific name, peruvianus, means "belonging to Peru".  The first specimen was discovered off the coast of Peru in 1991.  Information regarding this species stems from 12 specimens, which were found in Baja California and Peru.  These locations suggest this species' range includes the tropical waters of the western Pacific Ocean.  Body coloration is gray dorsally, fading to a lighter shade ventrally.  Adults grow to lengths of 10-12ft.  This is the smallest species of beaked whale.

 

Stejneger's beaked whale Mesoplodon stejnegeri

The specific name, stejnegeri, is named for Leonhard Hess Stejneger (1851-1943), a Norwegian zoologist working under Spencer Baird at the Smithsonian Institution.  He eventually became Head Curator of Biology at the Museum.  Interestingly, Stejneger wrote a biography of George Wilhelm Steller (1709-1746), a German zoologist responsible for studying and exploring life of the northern Pacific Ocean.  Steller discovered species of marine mammals unknown to science, including Steller's sea cow and Steller's sea lion.  This biography brought recognition to Steller's work, which had not been published.  The primary range of this species includes the temperate waters of the North Pacific.  Body coloration is dark gray dorsally, fading to a lighter shade ventrally.  Adults reach lengths of 9-16ft.

 

Content provided by Canisius College students under the direction of Michael Noonan, PhD.