Japan’s only male sea otter Riro died on January 4 at Marine World Uminonakamichi aquarium in Fukuoka City in southwestern Japan.

The popular sea otter was 17 years old, equivalent of the 70s for humans.

Riro was the only male of the 3 sea otters currently raised in Japan.

The sea otter was unavailable for viewing after he stopped eating on December 27. He received treatment, but died on the morning of January 4.

Riro was born in Adventure World in Wakayama Prefecture western Japan and transferred to Marine World in 2012.

The sea otter was loved by many for his adorable performances.

Since the death of Riro, just 2 female sea otters at Mie Prefecture’s Toba Aquarium remain in the country.