Tasmacetus shepherdiShepherd's beaked whale

Geographic Range

Although the geographic range of this species is not clearly known, Tasmacetus shepherdi (Shepherd's beaked whale, Tasman whale) probably has a circumpolar distribution in temperate waters of the southern hemisphere. All known specimens have been found on beaches in New Zealand, Australia, Brazil, Tierra del Fuego, Argentina, Chile, and the Galapagos Islands (Evans 1987, Tinker 1988).

Habitat

Based on stomach contents and locations where Tasmacetus shepherdi have washed ashore, this species is likely benthic and inhabits temperate waters of the southern hemisphere (Evans 1987, Tinker 1988).

Physical Description

The body of these whales is around 6-7 meters in length. The head is small with a long, narrow beak. The dorsal fin is small and is located 1/3 of the body length from the tail. The tail fluke is not notched, and the flippers are small and oval in shape. The back is uniform grayish-brown in color, fading to nearly white on the underbelly. Since very few of these whales have been seen while alive and body colors quickly darken following death, the true coloration of Tasmacetus shepherdi is not known (Evans 1987, Tinker 1988).

Shepherd's beaked whale can be easily distinguished from other members of the family Ziphiidae by the presence of 17-29 conical teeth in both the upper and lower jaw. Males possess two additional teeth on the anterior most part of the lower jaw. These teeth, described as possessing "bulbous bases and conical crowns", are larger than the homodont cheek teeth, and are separated from the cheek teeth by a 4 cm diastema. One tooth sits on either side of the mandibular symphysis (Walker 1975, Evans 1987, Tinker 1988).

The blowhole is crescent in shape and is asymmetrically located on the left side of the top of the head. The eye sits directly below the blowhole. The first five vertebrae are fused and the first through seventh pairs of ribs possess two heads (Evans 1987, Tinker 1988). (Evans, 1987; Tinker, 1988; Walker, 1975)

  • Range mass
    5600 to 6500 kg
    12334.80 to 14317.18 lb
  • Range length
    6 to 7 m
    19.69 to 22.97 ft

Reproduction

Nothing is currently known about the reproduction of this species.

  • Key Reproductive Features
  • gonochoric/gonochoristic/dioecious (sexes separate)
  • sexual

Behavior

Tasmacetus shepherdi has rarely been seen alive and very little is known about its behavior.

Communication and Perception

Food Habits

These whales eat squid and various fishes. Many of these fishes are benthic, suggesting that Tasmacetus shepherdi feeds at or near the sea floor (Tinker 1988).

  • Animal Foods
  • fish
  • mollusks

Economic Importance for Humans: Positive

Tasmacetus shepherdi is not economically important.

Economic Importance for Humans: Negative

none

Conservation Status

The IUCN lists Tasmacetus shepherdi under the "insufficiently known" category (Simmonds and Hutchinson 1996).

Other Comments

Very little is known about this rarely sighted whale. As of 1996, Tasmacetus shepherdi have been seen alive on only two occasions. Only around 10 beached specimens have ever been examined. The species was first described and named in 1937 and is the sole member of its genus. T. shepherdi is regarded as the most primitive ziphiid whale (Evans 1987, Harrison and Bryden 1988, Tinker 1988, Laughlin 1996).

Contributors

Gerhard Mundinger (author), University of Michigan-Ann Arbor, Phil Myers (editor), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

Atlantic Ocean

the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.

World Map

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map

benthic

Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

molluscivore

eats mollusks, members of Phylum Mollusca

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

References

Evans, P. 1987. The Natural History of Whales and Dolphins. New York, New York: Facts on File Publications.

Harrison, R., M. Bryden. 1988. Whales, Dolphins, and Porpoises. New York, New York: Facts on File Publications.

Laughlin, C. 1996. Scientific correspondence probable sighting of Tasmacetus shepherdi in the South Atlantic. Marine Mammal Science, 12(3): 496-497.

Simmonds, M., J. Hutchinson. 1996. The Conservation of Whales and Dolphins. New York, New York: John Wiley and Sons.

Tinker, W. 1988. Whales of the World. New York, New York: E. J. Brill.

Walker, E. 1975. Mammals of the World. Baltimore, MD: The Johns Hopkins University Press.