As It Happens

Finding Dory didn't endanger blue tang fish, say researchers studying the 'Nemo effect'

A new study suggests that there is no such thing as the "Nemo effect."

Study finds no evidence that pet sales increase after release of popular animal movies

Nemo, Marlin and Dory from the 2016 Disney animated movie Finding Dory. (Pixar Animation Studios/Walt Disney Pictures)

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When the Disney film Finding Nemo hit theatres, reports that clownfish sales skyrocketed sparked the term the "Nemo effect." 

So when the sequel Finding Dory came out 13 years later, starring a forgetful but lovable blue tang fish, there were concerns among conservationists that the wild population would suffer the same fate. 

But according to a new study published Wednesday in the journal Ambio, people weren't running out to buy the fish as a pet. 

"There's no Nemo effect after all," Diogo Verissimo, lead researcher and zoologist at the University of Oxford, told As It Happens guest host Nil Köksal 

What is the Nemo Effect? 

In 2003, the world watched as Marlin the timid clownfish searched the ocean for his missing son Nemo. 

"So many people were talking about the clownfish, and how cute it was and how nice it would be to have one as a pet," Verissimo said. 

According to media reports and conservationists, after Finding Nemo came out, the frenzy to buy the clownfish as a pet plummeted their numbers in the wild. 

It was dubbed the "Nemo effect," and the idea was also connected to owls from the Harry Potter films and various animals from Zootopia. 

A regal blue tang fish in a saltwater tank. (Benny Snyder/The Associated Press)

To test whether this was true, Verissimo and his team focused on the blue tang fish from Finding Dory. Since it was a more recent film, they had access to the data. 

"Our goal was to go beyond just one or two anecdotal reports, one or two, sort of, moral opinions of experts," he said. 

"We really wanted to get down to what the data had to say about these trends. Was it true or wasn't it true?" 

Study found no correlation

Blue tang fish are found in the Pacific Ocean and Indian Ocean, so in order to be in the United States, they would need to be harvested and imported. It is extremely difficult to breed blue tang fish in captivity. 

Verissimo said they worked with one of the major importers in the fish industry to see what kind of fish were being imported to the United States —  which had one of Finding Dory's largest viewerships —  after the movie's release. 

They compared the number of blue tang fish to other species within the same family that weren't a crucial part of the movie. 

They found there was no correlation between the time the movie came out and the number of blue tang fish imported to the United States. 

"We found out that we couldn't really find any evidence for a Nemo effect," Verissimo said. 

Diogo Verissimo is the lead researcher in the study about the so-called Nemo effect. (Oxford Martin School, University of Oxford)

They also looked at the snowy owl in the U.K. — the breed of Harry Potter's beloved pet Hedwig. 

Verissimo said in order to own a snowy owl as a pet in the U.K., a person must buy a special kind of ring with a registration number. 

"We looked at the release of the movies and actually also the release of the books, and we looked at how that mapped onto demand for owls," he said. 

They came to the same conclusion: no Nemo effect. 

Is overfishing a problem? 

In 2016, As It Happens spoke with Karen Burke da Silva, the founder of the Saving Nemo Conservation Fund. 

She warned that the overfishing of clownfish was linked to Finding Nemo, and that it could repeat itself with blue tang fish. 

Nemo, from the 2003 animated film Finding Nemo. (Pixar Animation Studios/Walt Disney Pictures)

Verissimo said he couldn't find any evidence that overfishing was linked specifically with Finding Dory — but that doesn't mean these fish aren't being targeted. 

"I think that's a distinction that's important to make," he said. 

"We're not saying that everything is fine with these species. We're not saying that everything is, you know, in top shape with their populations. What we're saying is that we don't find evidence that if there is a threat, that these threats are related [to] these big blockbusters." 

Films put spotlight on plight of fish 

Verissimo said the most important result from the study was that more people are researching how they can help save clownfish and blue tang fish. 

He noted that the movies pushed the fish, which don't get a lot of attention, into the public eye. 

"The lion's share goes to elephants, tigers and pandas, which, of course, they're really important species and they deserve to be conserved," he said. "But so do other species that have less public profile."

Written by Sarah Jackson. Produced by Ashley Mak. 


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