At a dam near Murray Bridge in South Australia, anticipation is building as three schools from opposite sides of Adelaide gather to release dozens of rare little river fish.
"I think all the children felt like surrogate parents because we'd reared them from little dots," said Kerry White, the principal of Holy Family Catholic School.
It is one of a handful of schools in South Australia working with not-for-profit organisation Aquasave to bring the southern purple-spotted gudgeon back from the brink of extinction.
"They were declared regionally extinct really from the '70s to '80s. No-one had found them," ecologist Sam Hardy said.
"And then back in 2002, the fish was found again, however, that was getting rarer and rarer."
Children fighting for fish's future
Sam Hardy says the children are playing a vital role in turning that around by breeding the small, slow-moving ambush predator that many people know nothing about.
"It's a great way to bring these younger people on board with what we're doing and to really get the message out there that these fish matter," the ecologist said.
For the director of Holy Family Catholic School's fish farm, it has also been quite the personal turnaround.
Mr McCarthy runs a business called Teach Fish SA, which he started after four decades of teaching and educational leadership roles.
He initially took students on fishing excursions, but when Holy Family Catholic School gave him the green light, he set up an aquaponics farm at the Parafield Gardens primary school.
It has been a big hit with students such as 10-year-old Kayden, who loves to feed the feisty barramundi.
While the well-known big barramundi are crowd-pleasers, it has been the addition of the lesser-known little purple-spotted gudgeon that has taken the project to the next level.
The school has been building a series of billabongs to cater for the growing population.
Fun learning
From designing the farm to maintaining it and looking after the residents, there are many valuable lessons in the hands-on fish centre.
One of the main lessons is about sustainable food production, with water from the tanks used to grow the school's extensive vegetable garden.
"The children who are most disinclined to school they love this because they don't see it as school, and sometimes they will say almost suspiciously 'am I learning'?" said principal Kerry White.
The fish precinct, which includes an interactive educational facility next door to the farm, has also been incorporated into more traditional subjects such as science, English and maths.
The school is home to more than 20 species of fish.
Hope for threatened species
In the meantime, back at the Murray Bridge reserve, it's time for students to say goodbye to their first batch of home grown gudgeon.
"I hope they will be happy in their new environment, and I hope they will stay healthy," said Javeiria, another student taking part.
Returning the threatened fish to the wild is a challenge in SA, with drought and carp taking a toll on their preferred habitat.
"They love the slower parts of the faster moving creeks and rivers," said Sam Hardy.
Previous releases at the site where they were last found in the River Murray, have not taken off.
So ecologists are now building up numbers in more suitable sites away from the river until they can get the real thing up to scratch.
Sam Hardy is confident the students' efforts to give the fish a fighting chance will pay off.
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