Over 100 New Species Discovered in Remote Australian Waters

More than 100 new species have been recorded and catalogued for the first time in some of Australia's most remote territorial waters.

The often bizarre benthic creatures were found dwelling across 22 seamounts, or massive subsea mountains, near the Christmas and Cocos (Keeling) Islands, nearly 3,000 kilometres north-west of Perth.

Scientists from the CSIRO and Australian Museum collected 1,000 specimens over two voyages in 2021 and 2022 aboard their 94-metre oceanographic research vessel, the Investigator.

Their findings, published this week, suggest at least 149 — everything from sea stars to worms to sea cucumbers — were unknown to humanity until now.

"It's an incredibly important environment, and we know nothing about it," paper co-author and jellyfish expert Claire Rowe said.

"Some of these specimens have been collected down to 5,000 metres below the surface. I can't even run 5ks.

Deep-sea 'flower'

One of the new species is among the deepest ever discovered in more than 100 voyages by the RV Investigator.

The annelid worm, which scientists have named Bathyvermilioides juliebrocka, is just millimetres long and was captured at a depth of around 4,990 metres.

The animal itself is a rare sight, beyond the feather-like tentacle that protrudes from its hard tubular shell of calcium carbonate.

"In a way, it looks like a little flower," explained Elena Kupriyanova, a deep-sea worm researcher and voyage crew member

Dr Kupriyanova said it was "surprising" to find a firm-bodied creature so far down, where others had evolved to be gelatinous under the crushing weight of roughly 500 atmospheres.

"Somehow these animals managed to calcify and maintain their tube despite this high pressure in the abyss," she said.

Dr Kupriyanova said the seamounts' rich biodiversity helped dispel the long-held "endemism" theory that these habitats had developed in isolation.

Instead, she likened them to "stepping stones", allowing deep-sea organisms to hop from one to the next in a chain of ecosystems.

"Because we can have examples of both unique fauna and actually quite common species on different seamounts around the world," Dr Kupriyanova said.

Snapshot of a world in flux

Almost half a decade later, the two expeditions of the RV Investigator continue to yield tranches of discoveries and a long string of publications, with more than 400 collected species still on the shelf, waiting to be described.

The often lengthy and laborious process requires scientists to prove their finds using genetic material and compare them against international databases.

Parks Australia acting director Alan White said the results offered important data for managing two of the authority's most distant and pristine marine parks.

The trips also involved mapping the sea floor using the vessel's advanced sonar system.

"What it does give us is a really great snapshot of what the deep-sea environment was like when the marine parks were created and what sort of species were there," he said.

Dr Rowe said it was especially critical for combating human impacts in the region.

"There are so many threats to our marine environment at the moment: overfishing, climate change," she said.

"The more we find now, the more we can understand how some species may adapt, how some species may not. It's all connected."