Australian researchers have found a much simpler, less technological way to determine what lives in the ocean.
It’s a game-changer for scientists who monitor global marine life, from sharks to kelp forests and everything in between.
For some time now, researchers have been collecting seawater and pumping it through a series of filters to capture environmental TBEN (eDNA) released by marine plants and animals.
This eDNA is then sequenced to precisely identify which species are present in specific areas.
If an area’s biodiversity begins to change, it can indicate trends such as dwindling fish stocks, deteriorating reef health, and even alien invasions that can threaten biosecurity.
– Olly Berry (@ OllyBerry4) February 23, 2021
But the task of harvesting eDNA has always taken time, forcing researchers to laboriously filter seawater at the point of collection, or return it to a lab for filtration.
It also required specialized equipment, including water pumps and access to an offshore power source, which is not easy.
But CSIRO researchers changed all that after finding a shortcut.
They found that cellulosic filter paper left to soak in the ocean successfully sucks up valuable eDNA, and it is not necessary to do the hard work of machine-assisted filtering.
The discovery means the whole process is faster, simpler, and can be done on a much larger scale.
Anyone with the right lightweight filter paper and a way to submerge and retrieve it could now play a role in monitoring marine biodiversity.
In theory, that could mean a whole new army of citizen scientists helping to build a more detailed picture of the world’s marine biome, which covers 70% of the planet.
It will also allow governments and industry to keep an eye on what is really going on beneath the waves.
“This means we can measure the environment at the scale and speed we really need. Anyone can do it anywhere, and you don’t need the equipment, ”says Dr. Olly Berry, director of the Environomics Future Science Platform at CSIRO.
It was CSIRO marine scientist Cindy Bessey who began to think about passive ways to collect eDNA after spending many hours at sea in a small rubber dinghy with a water filter strapped to her back.
“It would take me almost 30 minutes to filter the water through just three filter papers at one site. I knew I had to find a more efficient way if I was going to investigate 100 sites, ”she says.
A study of his passive immersion method shows that it works and that eDNA has been successfully harvested from the tropical reef of Ashmore and the temperate island of Daw, off the west coast of Australia.
“There is no longer a need to filter seawater to collect eDNA, saving time and opening up the technology for use in places where access to equipment or l ‘electricity is limited,’ said Dr Bessey.
CSIRO is currently developing a simple device for the passive collection of eDNA in marine and freshwaterways.
The results of the study were published in the Atlas of Living Australia.