A sunfish in Japan became ill when its aquarium was closed. Human incisors helped him recover.

A solitary sunfish at an aquarium in southwestern Japan lost its appetite, began bumping into the side of the aquarium, and appeared ill days after the facility was closed last month for renovations. As a final measure to save this popular fish, its keepers have hung up their uniforms and placed human cutouts outside the tank.

The next morning, the sunfish ate for the first time in about a week, and were steadily recovering, said Mo Miyazawa, an aquabiologist at the Kaikyōkan Aquarium in Shimonoseki.

The large sunfish arrived at the aquarium in February 2024 from the southern coast of Kochi in the Pacific Ocean. The sunfish, a member of the pufferfish family known for its unique shape and large eyes, has become one of the facility’s most popular attractions.

When the sunfish began to look sick days after the aquarium closed on December 1 for a six-month renovation, its keepers suspected digestive problems, gave it less food and visited the aquarium to calm the sunfish when there was construction noise. But they didn’t. Feasibility.

Then at a staff meeting, someone suggested that the sunfish might have been affected by the sudden absence of the public.

“We were skeptical but decided to do everything we could,” Miyazawa said. They hung up their uniforms and placed human-shaped cut-outs with pictures of smiling faces outside the tank to cheer up the fish, Miyazawa said.

“I knew it (the sunfish) was looking at us when we put it down, but I never thought it would start eating the next day,” Miyazawa said with a smile. Staff now visit frequently and wave at sunfish.

Aquarium keepers say they hope many fans will return to see sunfish when the aquarium reopens in the summer.