Japanese sea lion

The Japanese sea lion (Zalophus japonicus) (ニホンアシカ, ) was an aquatic mammal that became extinct in the 1970s. It was considered to be a subspecies of the related California sea lion (Z. californianus) until 2003. 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. They were hunted commercially in the 1900s, leading to their extinction. 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. DNA analysis in 2007 estimated that the divergence point between the two sea lions took place around 2 million years ago (mya) in the early Pleistocene. Several taxidermied specimens can be found in Japan and in the National Museum of Natural History, Leiden, the Netherlands, bought by Philipp Franz von Siebold. The British Museum possesses a pelt and four skull specimens. 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. Japanese sea lions were found along the northwest Pacific coastline, specifically in Japan, Korea, southern Kamchatka Peninsula, and the Sakhalin Island. However, they may not have existed in Kamchatka, with their northernmost range extending only to the Kuril Islands. Sightings of individual Japanese sea lions still persist in Korea, but these are probably misidentified Steller's sea lions (Eumetopias jubatus). The only reliable report may have been of an individual shot at Moneron Island in 1949. 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 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 (犬吠埼, dog-barking point) because of their howls to compared to dog's barking.