August 2, 2022
Image credit: Doug Gimesy
The whole continent is about to be treated like a crime scene as thousands of people across the country begin searching for DNA from the nation’s animals.
It’s all for a truly massive investigation dubbed the Great Australian Wildlife Search (GAWS) that’s being touted as not only the biggest single survey of biodiversity in the world, but also the largest deployment of citizen scientists ever seen anywhere. And it couldn’t come fast enough, with Australia, like the rest of the world, facing an unprecedented extinction crisis. An opportunity to show what, and where, animal species are located across this vast country will help government and conservation organizations better plan the allocation of resources to help save threatened wildlife.
The survey is being spearheaded by the not-for-profit conservation organization the Odonata Foundation, working in partnership with Melbourne-based biotech company EnviroDNA. Funding support worth multiple millions is expected from governments and philanthropists.
GAWS will be using a high-tech detection method on a scale that’s never been done before to find the animal species surviving across an entire continent. And it will do that by bringing on board as much of the nation’s population as it can to work as citizen scientists collecting the data. It’s being based on a technology known as eDNA, which can be used to look for the presence of animal species by detecting minute traces of DNA left, for example, from hair and skin cells.
Currently, the technology works best in water and so the GAWS testing sites will initially be beside and in rivers and streams. (In 2020 human health services in Australia and elsewhere began applying the same sort of technology to track the spread of COVID by searching for tell-tale genetic markers from the virus in waste water.)
Every time an animal swims in or drinks from a water course, the tiny traces of DNA that slough off from their bodies can be detected for up to two weeks afterwards. And these can be identified by comparing them against a library of known genetic markers for different species. Even if the DNA drops off in the terrestrial environment, it can be detected in a nearby water body when it’s carried there by run-off after rainfall.
Despite Australia being the most arid populated continent on Earth, most of our animals need to find water somewhere to drink – no matter how small or hidden the source may be.
What’s possible with this technology for wildlife is phenomenal!”
says Odonata CEO Sam Marwood.
“It’s going to give us a snapshot in time so we can turn the information into distribution models for both wild and feral species that will be better than we’ve had before. For us to be able to know where threatened wildlife is means we can plan where our sanctuaries go and where we can support wildlife corridors.” The information could also be used to identify whether there are important wildlife species on neighboring properties so that owners can manage their land accordingly.
The GAWS project has grown from previous work undertaken using eDNA in conjunction with Melbourne University-based ecological geneticist Dr Andrew Weeks.
The first scientific papers were written about eDNA from water in about 2008; Andrew began researching the technology extensively from 2012. His team first applied it in a project for Melbourne Water to identify where platypuses were located in the catchment under that state authority’s jurisdiction. The platypus is now a threatened species, and being aquatic, it provided a perfect opportunity for application of the technology.
Andrew’s team found that using eDNA was a lot more sensitive and cost-effective than using other methods, such as trapping, to identify where Victoria’s platypuses were. “We were able to show that by taking just two water samples from a site, we could detect more than 95 per cent of the time if platypuses were present,” Andrew explains. “To do that using traditional platypus surveys, we’d have to do 6–10 surveys, and each of those would go for an entire night.
“So you can see how cost efficiency and the technique’s sensitivity comes into it.”
From platypuses to any animal that ever comes near water, the use of eDNA grew in Victoria and Odonata saw the possibilities for monitoring wildlife. In 2021 a pilot project that applied the technology across the state was undertaken. With the help of an army of citizen scientists, at a cost of $900,000, 2000 sites were sampled. The results are due to become available in late 2022, but the project so went smoothly that it’s being scaled up nationally in the form of GAWS, which is due to kick off soon, operating in every state and territory across the country.
The sort of data that is expected to be produced would normally take at least 15 years to gather using traditional methods at a cost that would likely exceed $150 million, Andrew estimates.
For further information and to find out how you can become involved in the survey or donate to the project go to thegreataustralianwildlifesearch.org