During a month-long journey off the country’s eastern seaboard, the research vessel Investigator has surveyed life lurking in a dark and cold abyss that plunges 2.5 miles (four kilometers) below the surface, using nets, sonar, and deep-sea cameras.
Tim O’Hara from Museums Victoria, who serves as chief scientist on board, told AFP on Wednesday that the search area was “the most unexplored environment on earth.”
Bright red spiky rock crabs, puffed-up coffinfish, blind sea spiders, and deep sea eels have been collected since the scientists began their voyage — from Launceston in Tasmania north towards the Coral Sea — on May 15.
They also came across an unusual faceless fish, which has only been recorded once before by the pioneering scientific crew of HMS Challenger off Papua New Guinea in 1873.
At such huge depths, it is so dark that creatures often have no eyes or produce their own light through bioluminescence, he added.
Carnivorous sponges that wield lethal spicules made of silicon — effectively glass — were another striking find. They get small crustaceans hooked on their Velcro-like spines, to be slowly digested in-situ. This technique differs from most deep-sea sponges, which feed on bacteria and other single-celled organisms filtered from passing currents.
“We’ve got 27 scientists on board who are leaders in their fields, and they tell me that around one-third of what we’ve found are new species,” said O’Hara, with several thousand specimens so far retrieved and two weeks of the trip still to go.
As food is scarce, they are usually small and move slowly. Many are jelly-like and spend their lives floating about, while others have ferocious spines and fangs and lie in wait until food comes to them.
Working in such an environment was challenging, O’Hara admitted, with each fishing expedition taking up to seven hours to deploy and retrieve the equipment and its eight kilometers of cable from the sea floor, given it is so far down.
Read more at Discovery News