Mating into extinction

Mating into extinction

Project Information

Project Summary

An unexpected catch in the waters of the Running River sparked research into the potential extinction of the Running River rainbow fish. In 2015 IAE Dr Peter Unmack and Curator of Fishes at the Museum and Art Gallery of the Northern Territory, Dr Michael Hammer, were sampling for the usually supremely abundant Running River Rainbowfish. But something was wrong – they started finding a few Eastern Rainbowfish as well.

The Running River Rainbowfish is a small, strikingly coloured species that lives exclusively in a 13 km stretch of the Running River, north of Townsville in Queensland. Due to geographic constraints the Running River Rainbowfish have lived in isolation for thousands of years, and have evolved to become physically and genetically distinct from neighbouring rainbowfish species.

However, between 2012 and 2015 Eastern Rainbowfish were introduced to the upper reaches of Running River and began spreading downstream. Unfortunately the Running River Rainbowfish finds this invader particularly attractive, mating with them and genetically diluting their population to produce a hybrid swarm.

Researchers from the IAE captured Running River Rainbowfish at this crucial moment. “It was pure luck that we sampled this population when we did, as a few years later pure wild fish would have been difficult to find. Our research is the first to demonstrate Running River Rainbowfish is a new species which could have gone extinct prior to being formally recognized as a species,” says Dr Unmack.

Without formal conservation funding, IAE researchers had to look elsewhere to finance their work, and are collaborating with the Australian New Guinea Fishes Association and Diversity Arrays Technology. They also instigated a crowd funding effort and raised in excess of $10,000, with over half the donations from amateur aquarium clubs and aquarists from around the world. Crowd funding made possible the genetic testing of 207 wild caught and captive fish, informed captive breeding using wild caught fish at the University of Canberra, and shipped offspring to Townsville for ‘grow-out’ at James Cook University. Those fish are currently being released into two nearby creeks to provide a home to pure populations and thus ensure their conservation in wild habitats.