Stejneger's beaked whale (''Mesoplodon stejnegeri''), also known as the Bering Sea beaked whale or the saber-toothed whale, is a relatively unknown member of the genus ''

Mesoplodon Mesoplodont whales are 16 species of toothed whale in the genus ''Mesoplodon'', making it the largest genus in the cetacean order. Two species were described as recently as 1991 (pygmy beaked whale) and 2002 (Perrin's beaked whale), and marine ...

'' inhabiting the North Pacific Ocean.

Leonhard Hess Stejneger Leonhard Hess Stejneger (30 October 1851 – 28 February 1943) was a Norwegian-born American ornithologist, herpetologist and zoologist. Stejneger specialized in vertebrate natural history studies. He gained his greatest reputation with reptil ...

collected the type specimen (a beach-worn skull) on

Bering Island Bering Island (russian: о́стров Бе́ринга, ''ostrov Beringa'') is located off the Kamchatka Peninsula in the Bering Sea. Description At long by wide, it is the largest and westernmost of the Commander Islands, with an area of . ...

in 1883, from which

Frederick W. True Frederick William True (July 8, 1858 – June 25, 1914) was an American biologist, the first head curator of biology (1897–1911) at the United States National Museum, now part of the Smithsonian Institution. Biography He was born in Middletown, ...

provided the species' description in 1885. In 1904, the first complete skull (from an adult male that had stranded near

Newport, Oregon Newport is a city in Lincoln County, Oregon, United States. It was incorporated in 1882, though the name dates back to the establishment of a post office in 1868. Newport was named for Newport, Rhode Island. As of the 2010 census, the city had ...

) was collected, which confirmed the species' validity.True, F.W. 1910. ''An account of the beaked whales of the family Ziphiidae in the collection of the United States National Museum, with remarks on some specimens in other American museums''. Washington: Government Printing Office. The most noteworthy characteristic of the males is the very large, saber-like teeth, hence the name.

Description

The body for this species is typical for a mesoplodont, long and tapering at both ends. The beak is of medium length, and the mouthline forms an arch, though much smoother than other species. The teeth of the males are much larger than those of most other mesoplodonts and point forwards and inwards right in front of the apex. Only

strap-toothed whale The strap-toothed beaked whale (''Mesoplodon layardii''), also known as Layard's beaked whale, is one of the largest members of the mesoplodont genus, growing to in length and reaching up to . The common and scientific name was given in honor of ...

s and

spade-toothed whale The spade-toothed whale (''Mesoplodon traversii'') is a very little-known species, the rarest species of beaked whale. It was first named from a partial jaw found on Pitt Island, New Zealand, in 1872; reported and illustrated in 1873 by James He ...

s have longer teeth. The coloration is overall dark gray to black on the body with light coloration below, and around the head giving it a "helmeted" appearance. The coloration darkens with age, but females have a light pattern on the bottom of the flukes that becomes more apparent with age. Like most species, scars occur on the males (from other males) and

cookiecutter shark The cookiecutter shark (''Isistius brasiliensis''), also called the cigar shark, is a species of small squaliform shark in the family Dalatiidae. This shark occurs in warm, oceanic waters worldwide, particularly near islands, and has been reco ...

bites are present on both sexes. The length is at least 5.25 meters (17 feet 6 inches) for males and 5.5 meters (18 feet) for females. They are likely around 2.1 to 2.3 meters (7 to 8 feet) in length when born.

Population and distribution

This is the northernmost species of beaked whale in the Pacific Ocean, ranging up into the Bering Sea. They are distributed along both sides of the Pacific to

Miyagi Prefecture is a prefecture of Japan located in the Tōhoku region of Honshu. Miyagi Prefecture has a population of 2,305,596 (1 June 2019) and has a geographic area of . Miyagi Prefecture borders Iwate Prefecture to the north, Akita Prefecture to the nort ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

and southern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. They may migrate south in winter.

Behavior

The whales are typically found in groups of three to four and sometimes up to 15 animals in a very close group. The groups may have age and sex segregation. Adult males fight each other extensively, and some specimens have been found with healed jaw fractures.

Conservation

This species has been occasionally hunted in Japan in the past, and occasionally been caught in drift nets. It is uncertain how much this affects the population.

References

Sources

*''Encyclopedia of Marine Mammals''. William F. Perrin, Bernd Wursig, and J.G.M Thewissen, editors. Academic Press, 2002. *''Sea Mammals of the World''. Randall R. Reeves, Brent S. Steward, Phillip J. Clapham, and James A. Owell. A & C Black, London, 2002.

External links

Cetaceans of the WorldWhale & Dolphin Conservation Society (WDCS)Rare Stejneger’s Beaked Whale Beaches at Venice Beach, California
{{Taxonbar, from=Q1125029 Mesoplodont whales Mammals described in 1885 Taxa named by Leonhard Stejneger