Japan’s Ministry of the Environment officially declared the Japanese River Otter (Lutra lutra whiteleyi) extinct this week. The river otter, which had not been seen for more than 30 years, once numbered in the millions but was decimated by hunters, habitat destruction and pollution.

As Scientific American‘s John R. Platt reports, the otter grew about a meter long and lived on shrimp and fish. It still serves as the official animal symbol of Ehime Prefecture, located in northwestern Shikoku island. Locals last spotted the animal in 1979 in Kochi Prefecture on Shikoku, and a single photo exists from the event Over the years, several thorough searches for the otters in their old river playgrounds turned up nil.

In addition to the river otter, the least horseshoe bat, the Japanese subspecies of the Asian black bear, a bird species, an insect species and a shellfish species all joined Japan’s extinction list this week.

More from Smithsonian.com:

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