Issue 14
Monday, 15 August 2016
Charles Darwin University
The Critically Endangered largetooth sawfish
The Critically Endangered largetooth sawfish

Hi-tech test to find endangered sawfish

New technology is helping researchers in their search for a rare sawfish species found in remote Northern Australia.
Researchers from Charles Darwin and James Cook universities are using the cutting-edge eDNA (environmental DNA) technique to predict where to look for the Critically Endangered largetooth sawfish.

eDNA sampling involves collecting a small sample of water and analysing it for traces of a target species’ DNA. It has been made possible by major advances in the field of DNA collection and analysis, and is considered a revolutionary technology in the natural sciences.

JCU’s Professor Colin Simpfendorfer said researchers first sampled water from various aquaria and were able to determine which contained largetooth sawfish, before trying the technique in the wild. 

Thought to be extinct in 50 countries, Northern Australia is one of the last places the largetooth sawfish can be found with any reliability. CDU's Dr Peter Kyne has been researching a significant population of the species in the Northern Territory’s Daly River.

To test the eDNA approach in the wild, the research team partnered with the Malak Malak traditional owners and Indigenous rangers to sample known largetooth sawfish habitats.

“With plenty of sawfish habitat, Malak Malak country was the perfect place to test the new tool in the field,” Dr Kyne said. 

Professor Simpfendorfer said the technique was mostly accurate in waterholes, but to date disappointing in flowing rivers and was still in a trial phase.

He said the eDNA techniques were evolving rapidly and were a huge advance for species’ conservation.

“Sawfish are globally distributed and we don’t even know if they still exist in many countries,” he said. “Applying the eDNA approach globally will enable us to rapidly find threatened populations and prioritise their protection.”

Professor Simpfendorfer said the technique had the potential to be rolled out globally for uses such as detecting invasive pest species at ports.

The project was funded in part by the Australian Government’s National Environmental Research Program.