In the waters off the east coast of Australia, specifically under the Tasman Sea, a team of scientists has discovered something that human eyes have never seen before: a ‘lost world’ of gargantuan volcanoes more than 3,000 meters high.
It is an ancient highway of massive underwater volcanoes, and those submerged mountains serve as marine highways for whales, according to a press release from Australia’s national science agency, CSIRO.
“While we were over the seamount chain, the ship was visited by large numbers of humpback and long-finned whales,” said Eric Woehler, a seabird ecologist at the University of Tasmania and a member of the crew aboard the RV Investigator. during his recent expedition. “We estimate that at least 28 individual humpback whales visited us in one day, followed by a group of 60 to 80 long-finned whales the next day .”
Scientists had recently embarked on a 25-day tour of the Tasman Sea to study ocean productivity , the process by which microscopic phytoplankton convert sunlight into the carbon that supports entire ocean ecosystems. While observing local marine life, other crew members scanned for signs of phytoplankton activity and mapped previously unexplored chunks of the ocean floor using special sonar.
When the research vessel was 400 kilometers east of Tasmania, the crew observed spikes in phytoplankton activity. Sonar scans revealed that the activity coincided with the appearance of a gigantic chain of submerged volcanic mountains thousands of meters below the sea’s surface.
Sonar scans revealed that these hidden, underwater ridges rose from the seafloor some 5,000 meters below the water’s surface. Volcanoes varied in size and inclination; some were jagged peaks rising 3,000 meters above the seafloor, while others were vast, low plateaus. Each of the titanic hills and valleys was likely formed many millennia ago as a result of ancient volcanic activity in the area, the researchers note.
Today, this unusual ‘lost world’ likely provides habitats for an enormously diverse population of marine life.
According to experts, the overhanging mountains could serve as underwater “signs” on a migration highway for regional whales, helping guide them from their winter breeding grounds to their summer feeding grounds.
In addition to abundant phytoplankton and whale sightings, the RV Investigator team also reported seeing a significant variety of seabirds, including four species of albatrosses and petrels.
“This is a very diverse landscape and will undoubtedly be a biological hotspot that supports a dazzling array of marine life,” said Tara Martin, a researcher at the Commonwealth Scientific and Industrial Research Organization (CSIRO), the science agency. that operates the RV Investigator.
Scientists will have to further study these newly discovered seamounts to find out if they truly represent a “highway for marine life.” Two new expeditions to this vibrant and diverse new ecosystem will embark in November and December.
Reference: CSIRO (Commonwealth Scientific and Industrial Research Organization) Australia. Marine research vessel RV Investigator. https://www.csiro.au/en/News/News-releases/2018/Scientists-uncover-volcanic-lost-world
Image credit: CSIRO
