The only sea otter being reared in captivity in the Kanto area has died, according to the Aqua World aquarium in Ibaraki Prefecture.

Sea otters are designated as an endangered species and the death last month of Kanna, a female otter, leaves only eight in captivity at aquariums and other facilities in Japan.

(Photo supplied by Aqua World)

Kanna was born in 2003 at Suma Aqualife Park in Kobe and was raised from around 18 months old at Aqua World.

Kanna turned 15 years old on Oct. 25 but gradually lost her appetite entering November and died on the 27th of that month, according to Aqua World.

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