TOWNSVILLE, Australia (CNN) - About 15 years ago, the movie "Finding Nemo" caused the popularity of clownfish as pets to soar, and that is still causing problems for wild clownfish populations.
Their natural habitat is threatened by overfishing and warming ocean temperatures.
A program in Australia aims to save "Nemo."
The humble clownfish, though small, is one of the most instantly recognizable inhabitants of the world's coral reefs.
The 2003 animated film, "Finding Nemo," told the story of a father searching for his son Nemo after he's captured from the wild, but the movie's box office success has had some unintended consequences.
"After the film 'Finding Nemo,' there was a drastic spike in the number of fish people wanted for their aquarium," said Karen Burke da Silva, a marine biologist and the co-founder of a program called Saving Nemo. "And the places that they were getting those fish was actually from the wild. As the numbers kept coming out of the wild, they started getting very, very small in some places and in fact, in certain areas, became locally extinct."
Students at Belgian Gardens Primary School in the Australian city of Townsville are trying to change that.
As part of the Saving Nemo program, schoolchildren are helping breed baby clownfish.
"We breed them so we can give fish that we breed to people who want clownfish. So they don't have to take them out of the wild," student Imogen Everson, said.
The clownfish raised at the school are eventually traded away to pet shops in exchange for aquarium supplies.
Unfortunately, the clownfish is now facing an even bigger challenge: climate change.
Rising temperatures around the world are bleaching - in other words, killing off - coral and sea anemone. the habitats clownfish call home.
Marine biologist Jodie Rummer said it will take more drastic action to protect the clownfish.
"The way to protect them is a really, really big solution, and it has to do with ending our reliance on fossil fuels. That's directly related to the warming of the oceans is the emissions into the atmosphere," Rummer said.
For newcomers, the story of the little star of "Finding Nemo" may have another surprising plot twist.
"I'm not sure if everybody knows that clownfish are hermaphrodites," Burke da Silva said.
All clownfish are born male, and some eventually transform and grow into bigger females.
"Females are the largest. They're the top fish in the anemone. Everybody wants to be the female," Burke da Silva said.