Japanese Sea Lion
Encyclopedia
The Japanese Sea Lion is thought to have become extinct in the 1970s.
Prior to 2003 it was considered to be a subspecies
of California Sea Lion
as Zalophus californianus japonicus. However, it was subsequently reclassified as a separate species. Some taxonomists still consider it as a subspecies of the California Sea Lion. It has been argued that japonicus, californianus, and wollenbaeki
are distinct species because of their distant habitation areas and behavioral differences.
They inhabited the Sea of Japan
, especially around the coastal areas of the Japanese Archipelago
and the Korean Peninsula
. They generally bred on sandy beaches which were open and flat, but sometimes in rocky areas.
Currently, several stuffed specimens can be found in Japan and the National Museum of Natural History
, Leiden, the Netherlands
, brought by Philipp Franz von Siebold
. The British Museum
possesses a pelt and 4 skull specimens.
along the coastal areas of the Korean Peninsula
, the mainlands of the Japanese Archipelago
(the both sides on the Pacific Ocean
and Sea of Japan), the Kuril islands
, and southern tip of the Kamchatka Peninsula
.
Old Korean accounts also describe that the sea lion and Spotted Seal
(Phoca largha) were found in broad area containing the BoHai Sea
, the Yellow Sea
, and Sea of Japan. The sea lions and seals left a lot of relevant place names all over the coast line of Japan such as Ashika-iwa (アシカ岩, sea lion rock) and Inubosaki (犬吠崎, lit. dog-barking point) because of the similarity of their howls.
Many bones of the Japanese Sea Lion have been excavated from shell middens from the Jōmon period
in Japan while an 18th century encyclopedia, Wakan Sansai Zue
, describes that the meat was not tasty and they were only used to render oil for oil lamp
s. Valuable oil was extracted from the skin, its internal organs were used to make expensive Oriental medicine
, and its whiskers and leather were used as pipe cleaners and leather goods, respectively. At the turn of the 20th century, they were captured for use in circuses.
contributed to their habitat destruction. The most recent sightings of Zalophus japonicus are from the 1970's with the last confirmed record being a juvenile specimen captured in 1974 off the coast of Rebun Island
, northern Hokkaido.
initiated an effort to search for and reintroduce sea lions to their native habitat in the Sea of Japan. The National Institute of Environmental Research
of Korea was commissioned to conduct feasibility research for this project. In 2007, a joint research venture between North Korea, South Korea, Russia, and China was announced. Chinese and Russian waters will be searched for surviving sea lion populations, with hopes of reintroducing the animal to their native habitat. If the animal cannot be found, the South Korean government plans to relocate California sea lions from the United States. The South Korean Ministry of Environment supports the effort because of the symbolism, national concern, the restoration of the ecological system, and possible ecotourism.
Prior to 2003 it was considered to be a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of California Sea Lion
California Sea Lion
The California sea lion is a coastal sea lion of western North America. Their numbers are abundant , and the population continues to expand about 5% annually. They are quite intelligent and can adapt to man-made environments...
as Zalophus californianus japonicus. However, it was subsequently reclassified as a separate species. Some taxonomists still consider it as a subspecies of the California Sea Lion. It has been argued that japonicus, californianus, and wollenbaeki
Galápagos Sea Lion
The Galápagos sea lion , a species of sea lion, exclusively breeds on the Galápagos Islands and – in smaller numbers – on Isla de la Plata . Being fairly social, and one of the most numerous species in the Galápagos archipelago, they are often spotted sun-bathing on sandy shores or rock groups or...
are distinct species because of their distant habitation areas and behavioral differences.
They inhabited the Sea of Japan
Sea of Japan
The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It is bordered by Japan, North Korea, Russia and South Korea. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific...
, especially around the coastal areas of the Japanese Archipelago
Japanese Archipelago
The , which forms the country of Japan, extends roughly from northeast to southwest along the northeastern coast of the Eurasia mainland, washing upon the northwestern shores of the Pacific Ocean...
and the Korean Peninsula
Korean Peninsula
The Korean Peninsula is a peninsula in East Asia. It extends southwards for about 684 miles from continental Asia into the Pacific Ocean and is surrounded by the Sea of Japan to the south, and the Yellow Sea to the west, the Korea Strait connecting the first two bodies of water.Until the end of...
. They generally bred on sandy beaches which were open and flat, but sometimes in rocky areas.
Currently, several stuffed specimens can be found in Japan and the National Museum of Natural History
Naturalis
Naturalis is the national natural history museum of the Netherlands, based in Leiden. It originated from the merger of the Rijksmuseum van Natuurlijke Historie and the Rijksmuseum van Geologie en Mineralogie in 1984. In 1986 it was decided that the museum had to become a public museum and a new...
, Leiden, the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
, brought by Philipp Franz von Siebold
Philipp Franz von Siebold
Philipp Franz Balthasar von Siebold was a German physician and traveller. He was the first European to teach Western medicine in Japan...
. The British Museum
British Museum
The British Museum is a museum of human history and culture in London. Its collections, which number more than seven million objects, are amongst the largest and most comprehensive in the world and originate from all continents, illustrating and documenting the story of human culture from its...
possesses a pelt and 4 skull specimens.
Physical description
Male Japanese Sea Lions were dark grey and weighed up to 450 to 560 kg reaching lengths of 2.3 to 2.5 meters; these were larger than male California Sea Lions. Females were significantly smaller at 1.64 meters long with a lighter colour than the males.Range and habitat
Japanese Sea Lions were primarily found in the Sea of JapanSea of Japan
The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It is bordered by Japan, North Korea, Russia and South Korea. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific...
along the coastal areas of the Korean Peninsula
Korean Peninsula
The Korean Peninsula is a peninsula in East Asia. It extends southwards for about 684 miles from continental Asia into the Pacific Ocean and is surrounded by the Sea of Japan to the south, and the Yellow Sea to the west, the Korea Strait connecting the first two bodies of water.Until the end of...
, the mainlands of the Japanese Archipelago
Japanese Archipelago
The , which forms the country of Japan, extends roughly from northeast to southwest along the northeastern coast of the Eurasia mainland, washing upon the northwestern shores of the Pacific Ocean...
(the both sides on the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
and Sea of Japan), the Kuril islands
Kuril Islands
The Kuril Islands , in Russia's Sakhalin Oblast region, form a volcanic archipelago that stretches approximately northeast from Hokkaidō, Japan, to Kamchatka, Russia, separating the Sea of Okhotsk from the North Pacific Ocean. There are 56 islands and many more minor rocks. It consists of Greater...
, and southern tip of the Kamchatka Peninsula
Kamchatka Peninsula
The Kamchatka Peninsula is a peninsula in the Russian Far East, with an area of . It lies between the Pacific Ocean to the east and the Sea of Okhotsk to the west...
.
Old Korean accounts also describe that the sea lion and Spotted Seal
Spotted Seal
The spotted seal , also known as the larga 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...
(Phoca largha) were found in broad area containing the BoHai Sea
Bohai Sea
Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of Northeastern and North China. It is approximately 78,000 km2 Bohai Sea , also known as Bohai Gulf, Bohai, or Bo Hai, is the innermost gulf of the Yellow Sea on the coast of...
, the Yellow Sea
Yellow Sea
The Yellow Sea is the name given to the northern part of the East China Sea, which is a marginal sea of the Pacific Ocean. It is located between mainland China and the Korean Peninsula. Its name comes from the sand particles from Gobi Desert sand storms that turn the surface of the water golden...
, and Sea of Japan. The sea lions and seals left a lot of relevant place names all over the coast line of Japan such as Ashika-iwa (アシカ岩, sea lion rock) and Inubosaki (犬吠崎, lit. dog-barking point) because of the similarity of their howls.
Lifestyle and reproduction
They usually bred on flat, open and sandy beaches but rarely in rocky areas. Their preference was to rest in caves.Human uses
Jomon period
The is the time in Japanese prehistory from about 14,000 BC to 300 BC.The term jōmon means "cord-patterned" in Japanese. This refers to the pottery style characteristic of the Jōmon culture, and which has markings made using sticks with cords wrapped around them...
in Japan while an 18th century encyclopedia, Wakan Sansai Zue
Wakan Sansai Zue
The is a Japanese 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 activities of daily life, such as carpentry and fishing, as well as plants and animals, and...
, describes that the meat was not tasty and they were only used to render oil for oil lamp
Oil lamp
An oil lamp is an object 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 is continued to this day....
s. Valuable oil was extracted from the skin, its internal organs were used to make expensive Oriental medicine
Oriental medicine
Oriental medicine is a collective term for several types of medicine practiced in the Orient and/or the East.Under Oriental medicine is understood:* Traditional Chinese medicine* Traditional Korean medicine* Kampo...
, and its whiskers and leather were used as pipe cleaners and leather goods, respectively. At the turn of the 20th century, they were captured for use in circuses.
Extinction
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 overfishing caused harvest numbers to fall drastically to 300 sea lions by 1915 and to 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. It is even believed that submarine warfare during World War IIWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
contributed to their habitat destruction. The most recent sightings of Zalophus japonicus are from the 1970's with the last confirmed record being a juvenile specimen captured in 1974 off the coast of Rebun Island
Rebun Island
Rebun Island lies in the Sea of Japan off the northwestern tip of Hokkaidō, Japan. Rebun stretches 29 kilometers in the north-south direction and 8 kilometers east-west, covering about 80 square kilometers. The island is known for its alpine flowers and the 8-Hour Hiking Course which runs from one...
, northern Hokkaido.
Population revival efforts
The South Korean Ministry of EnvironmentSouth Korean Ministry of Environment
The Ministry of Environment is the South Korean branch of government charged with environmental protection. The current minister is Lee Man Ee...
initiated an effort to search for and reintroduce sea lions to their native habitat in the Sea of Japan. The National Institute of Environmental Research
National Institute of Environmental Research
The National Institute of Environmental Research, or NIER, is a quasi-governmental research agency operated by the South Korean government. Its president is Seong-Kyu Yoon. It is charged with environmental research, education, international cooperation, and setting criterion levels for various...
of Korea was commissioned to conduct feasibility research for this project. In 2007, a joint research venture between North Korea, South Korea, Russia, and China was announced. Chinese and Russian waters will be searched for surviving sea lion populations, with hopes of reintroducing the animal to their native habitat. If the animal cannot be found, the South Korean government plans to relocate California sea lions from the United States. The South Korean Ministry of Environment supports the effort because of the symbolism, national concern, the restoration of the ecological system, and possible ecotourism.