Australian fish breeders try to reverse plummeting clownfish population on the Great Barrier Reef after Finding Nemo turned the colorful species into a popular pet
- The Boyne Island Environmental Education Center is trying to breed clownfish
- Staff members hope the program will reduce the number taken from the wild
- Clownfish play an important role in the health of reefs, keeping anemone clean of debris while being able to hide from predators
- After Finding Nemo, people began taking the fish from reefs to sell to pet stores
A local environmental group in Australia is trying to reverse years of population decline for clownfish in the Great Barrier Reef.
Called Caring for Clownfish, the program is being conducted at the Boyne Island Environmental Education Center in Queensland.
The program is committed to helping clownfish breed in captivity to create an alternate supply of the colorful fish for pet shops, where they have been in high demand since 2003’s Finding Nemo made the them a prize pets.
Environmental educators in Australia are trying to breed clownfish in captivity to supply pet stores with an ethical source for the prized fish, so that people will stop taking them out of the Great Barrier Reef and other reef environments
‘A lot of people wanted to collect clownfish for their aquariums and, unfortunately, the only way to collect those fish was to pilfer them from the reef,’ the Boyne Island Environmental Education Center’s Michael Gabriel told ABC News.
The center estimates that around 90 percent of the roughly one million clownfish sold as pets every year have been taken out of the wild, mostly from ocean reefs.
Clownfish are a kind of anemonefish, meaning they form close symbiotic relationships with vast network of plant-like anemones that grow on ocean coral.
Clownfish have evolved with immunity to the toxic chemicals secreted by many anemones, which allows them to hide from predators inside the anemone’s thick tentacles.
In return, the clownfish help keep the anemone healthy by feeding on algae and other debris that would settle over them and inhibit their growth.
‘As more hobbyists want to have these beautiful fish in their reef systems at home, those numbers in the actual reef are declining quite rapidly,’ Gabriel said.
After the 2003 Pixar moving Finding Nemo, clownfish became a hugely popular pet and 90 percent of those available in pet shops are taken directly from the ocean
Without an active and balanced clownfish population, the symbiotic system no longer functions normally and anemones are put at heightened risk.
Another challenge for clownfish living in the shallow reef waters is the rise of light pollution from harbors, which even in small amounts can ruin the viability of an egg.
The Caring for Clownfish program first began in 2018, but it’s taken some time to perfect the environment to encourage the fish to mate.
Clownfish are a type of anemonefish, helping the plant-like creature stay clean of algae and debris in exchange for having a convenient hiding place from predators
‘They need to have the right temperature, the right water salinity or the right parameters of the water chemicals,’ Mr Gabriel said.
‘A whole bunch of things come together to make sure they have a really happy space to have their breeding cycle.’
Clownfish can lay up to 1,000 eggs in a month, out of which between 50 and 100 fish could become viable and hatch.
‘If you go online and are looking at different pet shops, there are some real specialty marine shops that do get a lot of their harvest from these sustainably or ethically caught fish off the reef so that would be the first point of call,’ Gabriel said.
CLOWNFISH FATHERS HAVE STRONG NURTURING INSTINCTS BECAUSE OF A ‘LOVE HORMONE’
One area where Finding Nemo had things right is the great lengths clownfish dads go to to support their offspring, just like Marlin.
Their parenting instincts are so strong that even if you place clownfish eggs from an unrelated nest near a bachelor anemonefish, he will take care of them.
Researchers previously found the love hormone behind this fathering behaviour.
And it’s very similar to oxytocin, the hormone that facilitates bonding between human mothers and their babies after childbirth.
Scientists, based at the University of Illinois at Urbana-Champaign, decided to study the brain chemistry behind this parental care.
So they took individual anemonefish that were fathering and gave them an injection of antagonists.
They then analysed how these drugs might either promote or inhibit male parental care.
They found that anemonefish rely on isotocin, a signalling molecule that is almost identical to oxytocin.
When the researchers blocked this hormone, they found that the anemonefish fathers stopped tending to their eggs.