A female bottlenose dolphin has died at a Japanese aquarium only weeks after breaking a national record of more than four decades in captivity, an official said Thursday.

Nana, thought to be around 47 years old, was discovered drowned on Tuesday at a natural cove of Shimoda Aquarium in Shizuoka, central Japan, said official Kiyoshi Sakamoto.

The death came less than a month after Nana reached 42 years and 10 months under human care, beating the previous record held by another dolphin at Kamogawa Sea World, southeast of Tokyo.

The aquarium will conduct an autopsy on the dolphin as the exact cause of its death could not immediately be established, said Sakamoto, adding that Nana had recently lost her appetite.

Many bottlenose dolphins die between the age of 10 and 15 years.

Nana, which drew media attention after breaking the record, was given an award and special residence certificate by the city of Shimoda last month.

"Nana was a symbol of our aquarium and had attracted a lot of fans with her cute behaviour," Sakamoto said.

"We miss her so much," he said, adding that the facility is considering holding a ceremony in the dolphin's memory.

Nana was captured off the coast of Ito in 1974 and had lived at the aquarium ever since. She gave birth to eight calves while also taking part in dolphin shows, the official said.

Dolphin shows are popular at Japanese aquariums, while some local fishermen hunt the animals for meat, which they say is a traditional part of their diet.

Source: AFP