Mola Mola

[Drunk Monk]

This fish stopped eating. Was it loneliness, or something else?

Published 6 hours ago

Stephanie MacLellan
Copy Editor 

Expert says there could be more reasons for odd behaviour

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⭐️HERE’S WHAT YOU NEED TO KNOW⭐️

• A giant sunfish at a Japanese aquarium stopped eating recently. 
  
• It happened after the facility closed for renovations.
  
• Staff thought it was because the fish was lonely.
  
• One expert says it could be because of the sounds from the renovations. 
  
• Keep reading to find out what staff did to help. ⬇️⬇️⬇️
  

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Something was fishy with one of the most popular animals at the Kaikyokan aquarium in Japan last month.
The giant ocean sunfish had stopped eating and it was looking a little ill. 
Its keepers thought the issue was that the aquarium no longer had visitors, so they hung up pictures of people around the tank. 
The fish recovered, and the story of the lonely sunfish and its new paper friends spread around the world. 
It’s a fun story, but was it really that simple? 
One expert we spoke to said the inner lives of fish are a lot more complicated than we think. 
But when it comes to this particular fish, he thinks there were probably other explanations for its loss of appetite.

CAPTION/CREDIT: In order to help the sunfish at the Shimonoseki Marine Science Museum in Japan, staff put cardboard cutouts of people in uniforms outside the tank. (Kaikyokan/The Associated Press)

What happened to the sunfish? 
Ocean sunfish are huge. 
They can weigh up to 2,268 kilograms (about as much as a small car) and grow three metres long and more than three metres tall, according to the Monterey Bay Aquarium.
They also look a little strange — relatively flat, with rubbery skin and a stumpy tail.
“They have this sort of Humpty Dumpty face and huge eyes,” said Chris Harvey-Clark, a marine biologist and director of animal care at Dalhousie University in Halifax, Nova Scotia. 

The sunfish at the Kaikyokan aquarium in Shimonoseki, Japan, has lived there since February 2024. 
After the aquarium closed on Dec. 1 for a six-month renovation, it stopped eating, began banging into the side of the fish tank and appeared unwell. 
Staff thought it might have been affected by the sudden absence of visitors.
So they hung their uniforms, cardboard cutouts of people and photos of smiling faces outside the tank to make it look like the fish had visitors.
It started eating again the next day and its health soon improved.
Staff now visit the tank more often and wave at the sunfish.

The sunfish at the Shimonoseki Marine Science Museum swims near cardboard cutouts of people in uniforms on Jan. 21. (Kaikyokan/The Associated Press)

Fish are complicated, says expert
Harvey-Clark says there could be a lot of reasons why the sunfish lost its appetite, especially if noisy renovations at the aquarium had already started.  
“Fish are super sensitive to low-frequency vibration,” he said.
“We’re building a big aquarium at Dalhousie right now, and I can tell you when we start cutting concrete in a giant concrete building … the fish that are in our holding areas hundreds of [metres] away change their behaviour.”
Fish evolved to be highly sensitive to sounds and vibrations because they live underwater where there is low visibility, so they can’t always rely on their eyesight, he said.

It is possible the sunfish in Japan was affected by the lack of visitors, Harvey-Clark said, but that’s because fish in aquariums often respond to changes in activity patterns — not necessarily because it was feeling the emotion of loneliness.
He’s also skeptical that the human faces and cutouts made much of a difference, saying it’s likely a “coincidence” the fish started eating again because it would have been getting hungry anyway. 
But whether or not the sunfish was lonely, Harvey-Clark says this story is a good reminder that fish aren’t as simple as people often believe. 
“I think the big picture is, the next time you think about a fish, think about the world it lives in,” he said. 
“And it may not look a lot like you, but it’s still got two eyes, a mouth and a face and a head, and there’s a lot more going on there than you think.”