On the brink of extinction, time for the endangered Running River Rainbowfish was quickly running out.
In 2015, scientists from the University of Canberra's Institute of Applied Ecology, and the Museum and Art Gallery of the Northern Territory, discovered that the Eastern Rainbowfish had been released into the upper reaches of the Running River - the home of the Running River Rainbowfish.
As a result of interbreeding, the species was about to be wiped out - but that is when the Australian Wildlife Conservancy's Mount Zero-Taravale Wildlife Sanctuary stepped in and helped turn the tides.
After conducting genetic analysis to make sure they'd caught the target species, a captive breeding program was set up at the University of Canberra and James Cook University.
Over 4000 of the colourful, freshwater species were relocated to Deception Creek and Puzzle Creek at Mount Zero-Taravale, where no other rainbow species was found or could infiltrate the population.
With support from the Australian Wildlife Conservancy's team on the ground, University of Canberra Masters student Karl Moy undertook 10 releases of 250 fish at sites on Deception Creek, and four releases of 375 fish each along Puzzle Creek in late 2016 and 2017.
Through years of observation, researchers have now determined that the species is thriving and spreading into available habitat.
The Running River Rainbowfish evolved and survived in isolation, separated from the more common Eastern Rainbowfish by a series of gorges and waterfalls that prevented them from mingling.
"We're still just getting to understand the diversity of different rainbowfish in some of these Queensland catchments, so when we realised this unique species was under threat in its only habitat, we felt compelled to intervene," Dr Peter Unmack said.
"Saving the Running River Rainbowfish is a really, really big deal.
"It's only the second example in Australia where a fish has been saved from extinction when it was on the brink of being lost in its only habitat.
"AWC was instrumental in helping to save the Running River Rainbowfish."