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Scientists Detect an Elusive Giant Squid and Many Other Surprising Marine Animals Near Western Australia Thanks to DNA in the Water
Key takeaways
- The team surveyed underwater canyons in the eastern Indian Ocean about 750 miles north of Perth, during an expedition in the spring of 2020 aboard the U.S.-based Schmidt Ocean Institute’s RV Falkor.
- So, what that means is that we know that the animal was present in the environment of sampling within a timescale of at least a day.”
- Comparing the gathered eDNA to genetic reference data revealed that a surprising ocean neighbor had recently swum by: a rare giant squid.
A study published in March in the journal Environmental DNA is no different, though the researchers, who investigated life in deep marine canyons off Western Australia’s Ningaloo coast, used a technique that doesn’t involve capturing or even seeing the creatures in question.
The team surveyed underwater canyons in the eastern Indian Ocean about 750 miles north of Perth, during an expedition in the spring of 2020 aboard the U.S.-based Schmidt Ocean Institute’s RV Falkor. They collected nearly 200 water samples at five different depths, up to 2.8 miles below the surface, and then extracted the environmental DNA, or eDNA, hidden within. These bits of genetic material are left behind by animals in their mucus, feces, skin and other shed tissue.
“We can take these fragments, match them to a database, and then see what species were living there without actually having to see them on cameras,” lead author Georgia Nester, a molecular ecologist now at the University of Western Australia, explains in a video. “In marine environments, [eDNA] degrades pretty quickly, up to a scale of hours to days. So, what that means is that we know that the animal was present in the environment of sampling within a timescale of at least a day.”