\n<\/p>\n
The scientists didn’t need to see the marine animals to know they are living in Australia’s deep waters \u2013 instead, they detected their presence through water samples.\u00a0<\/p>\n
\nAs animals live out their lives, they shed tiny DNA particles through skin, mucus and faeces. Researchers can figure out what swam by recently by collecting small seawater samples and analysing them to detect these tiny traces (known as environmental DNA, or eDNA).\u00a0<\/p>\n
The scientists conducted surveys of the deep-sea Cape Range and Cloates canyons, which are located around 1,200km north of Perth, to try to find out more about the region\u2019s hidden biodiversity. They collected many different samples, some even as deep as 4,510m.<\/p>\n
The findings were published recently in the journal Environmental DNA<\/a><\/em>.<\/p>\n “These canyons are incredibly rich ecosystems and, until now, they\u2019ve been largely unexplored because of the difficulty of working at such extreme depths,”\u00a0said the study\u2019s lead author\u00a0Georgia Nester<\/a>. Nester is now a researcher at the University of Western Australia<\/a> but was a PhD candidate at Curtin University<\/a> at the time.\u00a0<\/p>\n “With eDNA, a single water sample can tell us about hundreds of species at once. That means we can dramatically expand our understanding of deep-water environments in a way that simply hasn\u2019t been possible before,” she adds.<\/p>\n The eDNA results helped them to paint a picture of life far below the waves, even when they didn\u2019t directly observe many of the elusive species. Perhaps one of the biggest surprises was the presence of a giant squid<\/a>, a rarely seen deep-sea\u00a0cephalopod<\/a>\u00a0that has not been recorded in Western Australian waters for more than 25 years.\u00a0<\/p>\n “This is the first record of a giant squid detected off Western Australia\u2019s coast using eDNA protocols and the northernmost record of [the species]\u00a0A. dux\u00a0<\/em>in the eastern Indian Ocean,\u201d says\u00a0Dr Lisa Kirkendale<\/a>, WA Museum Head of Aquatic Zoology and Curator of Molluscs.\u00a0<\/p>\n