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Creature 
Fast Facts

Introducing you to extinct species.

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THE JAPANESE

OTTER

1. The Japanese otter, Lutra nippon, is sometimes called the Japanese river otter. In Japanese it is called Nihon-kawauso which is written, ニホンカワウソ(日本川獺. 2. In the 1800’s, it was thought to be a subspecies of the Eurasian otter and was called Lutra lutra whiteleyi. DNA testing of preserved specimens in 2019 revealed the Japanese otter to be a unique species and labeled it Lutra nippon. 3. The total length of the Japanese otter from head to tail was around 48 inches long. They had short webbed feet and were excellent swimmers. 4. Its fur was dark brown with a lighter brown stomach and throat region. This otter adapted to its environment by shedding its under fur in May and its guard hairThe in August. 5. Like other otters, the Japanese otter was curious and playful. They used a lot of energy and would eat 15% - 25% of their body weight. They had short webbed feet and were excellent swimmers. 6. They were mostly nocturnal, choosing to eat fish, eels, crabs, and insects at night. 7. The Japanese otter had a lifespan of 25 years. 8. One otter territory had a radius of 5 miles. In the mid-1800’s they could be found throughout Japan, even in Tokyo. This otter was always on the move, visiting each of three to five dens within its range every few days. 9. A female otter would have 2 - 6 pups that would be born blind and helpless. During their time together she would teach them how to hunt. 10. In Japanese culture, the otter’s liver was used as a medicine to treat tuberculosis. Japan’s mythological Kappa spawned from the Japanese otter. It was also the official animal symbol of Japan's Ehime Prefecture. 11. The fur trade started during the Meiji Period in Japan, from 1868 - 1912 took a significant toll on the otter population. The last confirmed Japanese otter sighting was in 1979. It was declared extinct by Japan’s Ministry of the Environment on August 28, 2012.

Extinction 
Cometh

Facing the light at the end of the tunnel

EXTINCTION DATE

1979

The Japanese otters were once plentiful across most of Japan. Historically, these otters could be found in most places, even in Tokyo. They were sometimes hunted for their fur or for their livers, which the Japanese used as a medicine to treat tuberculosis. It wasn’t until the Meiji Period which started in 1868, that the Japanese otter faced any intense pressure. During the Meiji period, Japan started trading with outside nations. The fur trade was in full swing during this time. Around the world animal fur was an economic driver. Hunters started targeting the Japanese otters throughout this time. Japan did put hunting regulations in place after the severe decline in the otter’s population. The Japanese otter was deemed a “special natural treasure of Japan” in 1965. The otters were able to rebound slightly during this time, but ultimately they could not compete with the habitat alterations and the decline in its food sources due to urbanization. The otters were also killed by dogs and by cars while crossing the roads. The last confirmed sighting of a Japanese otter was in the Kochi Prefecture in 1979. There have been many hopeful signs that the Japanese otters still exist. Excrement found in 1994 & 1995 turned out to be from a raccoon dog. In 2009, 2014, and as recently as February 2017 wild otters have been seen, even on camera. Those otters were confirmed to be Eurasian otters that have started to move into the void left by the extinction of the Japanese otters. Although Jurassic Park is fiction, scientists are working on several de-extinction projects. In fact, in 2003 scientists did bring back the extinct Pyrenean ibex, a type of wild goat, for 7 minutes before it died, showing de-extinction is possible. The Japanese otter might be a good candidate. Scientists would potentially use DNA from the same museum specimens they used to test its genetics to confirm its unique species status in 2019. If the Japanese otter was brought back from extinction could it survive in the waters of Japan today?

Lazarus
Tales

Short stories of return

COMING SOON

The Japanese otter's Lazarus tale has yet to be written, but what adventures will await it when it returns to Japanese waters? Stay tuned to find out.

More to Explore
All answers lead to more questions

Photo of a Japanese otter specimen
Image from National Science Museum Taito City

Japanese otter specimen  
Image from Encyclopedia MDPI

Painting of a Japanese otter that 
Image from Lost Zoo

 One of the last Japanese otter specimens ever collected in 1977
Image from Longdom

Japanese otter specimen in National Museum of Nature in Science in Tokyo 
Image from Wikipedia

Japanese otter stuffed specimen
Image from Wikipedia

Photo of a Japanese otter that was kept at the Tobe Zoo in Japan
Image from Lost Zoo

Photo of a Japanese otter that was kept at the Tobe Zoo in Japan
Image from Lost Zoo

A 1949 painting called "Priest Otter" by Kawabata Ryûshi
Image from Wikimedia Commons

Japanese otter commemorative stamp
Image from Smithsonian Magazine

A craft of the extinct Japanese otter
Image from Yamaha Motors

My Japanese otter sketch brought to life
Image made with Gemini

My Japanese otter sketch brought to life
Image made with Gemini

Japanese sea lions were historically hunted for oil and for medicine.  This photo from 1934 shows sealing on Liancourt Rocks in Japan
Image from Wikipedia

A photo of the Japanese sea lion taken in 1934
Image from Wikipedia

The Japanese sea lion range did not overlap with the California sea lion, but its exact range is unknown
Image from Science Direct

A manhole cover design in 
Oki-no-shima island depicting the Japanese sea lion
Image from Lost Zoo

"Kaikidan Ekotoba monster scroll"
Image from Pink Tentacle

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