The Japanese sea lion (''Zalophus japonicus'') ( ja, ニホンアシカ, translit=Nihon ashika,
Korean
Korean may refer to:
People and culture
* Koreans, ethnic group originating in the Korean Peninsula
* Korean cuisine
* Korean culture
* Korean language
**Korean alphabet, known as Hangul or Chosŏn'gŭl
**Korean dialects and the Jeju language
** ...
:강치, 바다사자) was an aquatic mammal that became
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
in the 1970s. It was considered to be a subspecies of the related
California sea lion
The California sea lion (''Zalophus californianus'') is a coastal eared seal native to western North America. It is one of six species of sea lions. Its natural habitat ranges from southeast Alaska to central Mexico, including the Gulf of C ...
(''Z. californianus'') until 2003. They inhabited the
Sea of Japan
The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it h ...
, especially around the coastal areas of the
Japanese Archipelago
The Japanese archipelago (Japanese: 日本列島, ''Nihon rettō'') is a archipelago, group of 6,852 islands that form the country of Japan, as well as the Russian island of Sakhalin. It extends over from the Sea of Okhotsk in the northeast to t ...
and the
Korean Peninsula
Korea ( ko, 한국, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic o ...
. They generally bred on sandy beaches which were open and flat, but sometimes in rocky areas. They were hunted commercially in the 1900s, leading to their extinction.
Taxonomy
Prior to 2003, it was considered to be a
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of
California sea lion
The California sea lion (''Zalophus californianus'') is a coastal eared seal native to western North America. It is one of six species of sea lions. Its natural habitat ranges from southeast Alaska to central Mexico, including the Gulf of C ...
as ''Zalophus californianus japonicus''. However, it was subsequently reclassified as a separate species.
DNA analysis in 2007 estimated that the divergence point between the two sea lions took place around 2
million years ago
The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds.
Usage
Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago). ...
(mya) in the
early Pleistocene
The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...
.
Several taxidermied specimens can be found in Japan and in the
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2021, with 7 ...
,
Leiden
Leiden (; in English and archaic Dutch also Leyden) is a city and municipality in the province of South Holland, Netherlands. The municipality of Leiden has a population of 119,713, but the city forms one densely connected agglomeration wit ...
, the
Netherlands
)
, anthem = ( en, "William of Nassau")
, image_map =
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of the Netherlands
, established_title = Before independence
, established_date = Spanish Netherl ...
, bought by
Philipp Franz von Siebold
Philipp Franz Balthasar von Siebold (17 February 1796 – 18 October 1866) was a German physician, botanist and traveler. He achieved prominence by his studies of Japanese flora (plants), flora and fauna (animals), fauna and the introduction of ...
. The
British Museum
The British Museum is a public museum dedicated to human history, art and culture located in the Bloomsbury area of London. Its permanent collection of eight million works is among the largest and most comprehensive in existence. It docum ...
possesses a pelt and four skull specimens.
Description
![Zalophus_japonicus](https://upload.wikimedia.org/wikipedia/commons/8/84/Zalophus_japonicus.JPG)
Male Japanese sea lions were dark grey, reaching lengths of and weighed about . Females were significantly smaller at long and weighed about with a lighter grey colour than the males.
Distribution and habitat
Japanese sea lions were found along the northwest Pacific coastline, specifically in Japan, Korea, southern
Kamchatka Peninsula
The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and we ...
, and the
Sakhalin Island
Sakhalin ( rus, Сахали́н, r=Sakhalín, p=səxɐˈlʲin; ja, 樺太 ''Karafuto''; zh, c=, p=Kùyèdǎo, s=库页岛, t=庫頁島; Manchu: ᠰᠠᡥᠠᠯᡳᠶᠠᠨ, ''Sahaliyan''; Orok: Бугата на̄, ''Bugata nā''; Nivkh: ...
. However, they may not have existed in Kamchatka, with their northernmost range extending only to the
Kuril Islands
The Kuril Islands or Kurile Islands (; rus, Кури́льские острова́, r=Kuril'skiye ostrova, p=kʊˈrʲilʲskʲɪjə ɐstrɐˈva; Japanese: or ) are a volcanic archipelago currently administered as part of Sakhalin Oblast in the ...
.
Sightings of individual Japanese sea lions still persist in Korea, but these are probably misidentified
Steller's sea lion
The Steller sea lion (''Eumetopias jubatus''), also known as the Steller's sea lion and northern sea lion, is a near-threatened species of sea lion in the northern Pacific. It is the sole member of the genus ''Eumetopias'' and the largest of t ...
s (''Eumetopias jubatus''). The only reliable report may have been of an individual shot at
Moneron Island
Moneron Island, (russian: Монерон, ja, 海馬島 Kaibato, ja, トド島 Todojima, Ainu: Todomoshiri) is a small island off Sakhalin Island. It is a part of the Russian Federation.
Description
Moneron has an area of about and a high ...
in 1949.
Old Korean accounts also describe that the sea lion and
spotted seal
The spotted seal (''Phoca largha''), also known as the larga seal or largha seal, is a member of the family Phocidae, and is considered a "true seal". It inhabits ice floes and waters of the north Pacific Ocean and adjacent seas. It is primarily ...
(''Phoca largha'') were found in broad area containing the
BoHai Sea
The Bohai Sea () is a marginal sea approximately in area on the east coast of Mainland China. It is the northwestern and innermost extension of the Yellow Sea, to which it connects to the east via the Bohai Strait. It has a mean depth of a ...
, the
Yellow Sea
The Yellow Sea is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula, and can be considered the northwestern part of the East China Sea. It is one of four seas named after common colour terms ...
, and Sea of Japan.
The sea lions and seals left relevant place names all over the coast line of Japan, such as Ashika-iwa (海驢岩 or 海鹿岩, sea lion rock) and Ashika-jima (海獺島 or 海鹿島, sea lion island), and
Cape Inubō
is a cape on the Pacific Ocean, in Chōshi, Chiba Prefecture, Japan. The cape is near the midpoint of the Japanese Archipelago on the island of Honshū.
Origin of name
The name of the cape is constructed from two Chinese characters, the first ...
(犬吠埼, dog-barking point) because of their howls to compared to dog's barking. Bones of ''Z. japonicus'' dating to 3500–2000 BC were found in the
Shell Mound in Dongsam-dong, Busan. Genetic evidence confirms the former presence of ''Z. japonicus'' on the
Liancourt rocks
The Liancourt Rocks, also known by their Korean name of Dokdo or their Japanese name of Takeshima,; ; . form a group of islets in the Sea of Japan between the Korean peninsula and the Japanese archipelago. The Liancourt Rocks comprise two ...
.
They usually resided on flat, open, and sandy beaches, but rarely in rocky areas. Their preference was to rest in caves.
Exploitation and extinction
![Live catching of Sealion in Takeshima, by Japanese fishermans](https://upload.wikimedia.org/wikipedia/commons/9/95/Live_catching_of_Sealion_in_Takeshima%2C_by_Japanese_fishermans.jpg)
Many bones of the Japanese sea lion have been excavated from
shell midden
A midden (also kitchen midden or shell heap) is an old dump for domestic waste which may consist of animal bone, human excrement, botanical material, mollusc shells, potsherds, lithics (especially debitage), and other artifacts and ecofact ...
s from the
Jōmon period
The is the time in Japanese history, traditionally dated between 6,000–300 BCE, during which Japan was inhabited by a diverse hunter-gatherer and early agriculturalist population united through a common Jōmon culture, which reached a c ...
in Japan while an 18th-century encyclopedia, ''
Wakan Sansai Zue
The is an illustrated Japanese ''leishu'' encyclopedia published in 1712 in the Edo period. It consists of 105 volumes in 81 books. Its compiler was Terashima or Terajima (), a doctor from Osaka. It describes and illustrates various activitie ...
'', describes that the meat was not tasty and they were only used to render oil for
oil lamp
An oil lamp is a lamp used to produce light continuously for a period of time using an oil-based fuel source. The use of oil lamps began thousands of years ago and continues to this day, although their use is less common in modern times. Th ...
s. Valuable oil was extracted from the skin, its internal organs were used to make expensive
medicine
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pract ...
, and its whiskers and skin were used as pipe cleaners and leather goods, respectively. At the turn of the 20th century, they were captured for use in circuses.
Harvest records from Japanese commercial fishermen in the early 1900s show that as many as 3,200 sea lions were harvested at the turn of the century, and overhunting caused harvest numbers to fall drastically to 300 sea lions by 1915 and to a few dozen sea lions by the 1930s. Japanese commercial harvest of Japanese sea lions ended in the 1940s when the species became virtually extinct. In total, Japanese trawlers harvested as many as 16,500 sea lions, enough to cause their extinction. Submarine warfare during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
is even believed to have contributed to their habitat destruction.
The most recent sightings of ''Z. japonicus'' are from the 1970s, with the last confirmed record being a juvenile specimen captured in 1974 off the coast of
Rebun Island
is an island in the Sea of Japan off the northwestern tip of Hokkaidō, Japan. The island sits off the coast of Hokkaidō. Rebun stretches from north to south and from east to west. The island covers approximately . Rebun Island is located ...
, northern Hokkaido. There were a few unconfirmed sightings in 1983 and 1985.
The last credible documentation was made in 1951 on the
Liancourt Rocks
The Liancourt Rocks, also known by their Korean name of Dokdo or their Japanese name of Takeshima,; ; . form a group of islets in the Sea of Japan between the Korean peninsula and the Japanese archipelago. The Liancourt Rocks comprise two ...
reporting 50 to 60 animals. In any case, it was one of the most recent marine mammal extinctions to occur, alongside the
Caribbean monk seal
The Caribbean monk seal (''Neomonachus tropicalis''), also known as the West Indian seal or sea wolf, was a species of seal native to the Caribbean which is now believed to be extinct. The main predators of Caribbean monk seals were sharks and h ...
which went extinct at around the same time.
Attempted revival
In 2007, the
South Korean Ministry of Environment announced that
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...
,
North Korea
North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korea, Korean Peninsula and shares borders with China and Russia to the north, at the Yalu River, Y ...
,
Russia
Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
, and
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
will collaborate on bringing back sea lions to the
Sea of Japan
The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it h ...
, starting with a search for any Japanese sea lions that might still be alive. The
National Institute of Environmental Research of South Korea was commissioned to conduct feasibility research for this project. If the animal cannot be found, the South Korean government plans to relocate California sea lions from the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
.
The South Korean Ministry of Environment supports the effort because of the symbolism, national concern, the restoration of the ecological system, and possible
ecotourism
Ecotourism is a form of tourism involving responsible travel (using sustainable transport) to natural areas, conserving the environment, and improving the well-being of the local people. Its purpose may be to educate the traveler, to provide funds ...
.
Post-extinction claimed sightings or vagrant records
Sightings of single sea lions of unclear identities have been reported at
Iwami, Tottori
is a town located in Iwami District, Tottori Prefecture, Japan.
Iwami lies entirely within the San'in Kaigan Geopark.
Geography
Located in eastern Tottori, Iwami faces the Sea of Japan to the north. As of June 1, 2016, the town has an estimat ...
in July 2003, and on
Koshikijima Islands
The in the East China Sea are an island chain located 38 km west of the port city of Ichikikushikino, Kagoshima.
Major islands
Minor islands
All minor islands are currently (as in 2017) uninhabited.
#seems to undergo significant erosi ...
in March, 2016.
【動画】どこから来た?鹿児島近海でアシカ発見
/ref> Both animals were positively identified as Otariidae based on photographs, but their identities are unclear.
References
External links
*
*
{{Taxonbar, from=Q840036
Zalophus
Extinct carnivorans
Extinct animals of Japan
Mammal extinctions since 1500
Extinct mammals of Asia
Species made extinct by human activities
1974 in the environment
Mammals of Japan
Mammals of Korea
Mammals of Russia
Pinnipeds of Asia
Mammals described in 1866
Taxa named by Wilhelm Peters