Deep-sea lifeform rarities, 20 possible new species and a new 3km-high seamount have been found across a submerged South Pacific mountain chain during a month-long expedition led by the Schmidt Ocean Institute (SOI).
The discoveries were made along the Nazca Ridge, 1,450km off the coast of Chile, using multibeam echo-sounding equipment from the research vessel Falkor to map the area, and exploring it more closely from the ROV SuBastian.
The scientists mapped in high resolution the as-yet unnamed seamount, which covers an area of about 70sq km, and found that it rose more than 3km from the seabed, from a depth of 4.1km to just under 1km from the surface.
When the 4.5km-rated SuBastian carried out an exploratory dive on one its ridges it came across sponge gardens and ancient corals.
The team also mapped and explored nine other currently unprotected seamounts, one of which harboured what was described as a pristine 800sq m deep-sea coral garden, colonised by creatures such as rockfish, brittlestars and king crabs.
The team also captured the first camera footage of a live Promachoteuthis squid. This genus is so rare that only three species have ever been described, based on a few dead samples found in nets, several in the late 19th century.
Other rarities included the first Casper octopus to be seen in the South Pacific. Discovered in 2016 the blue octopus has yet to be scientifically described or formally named, and it was seen at a depth of 4,443m. Also prized sightings were two Bathyphysa siphonophores, aka “flying spaghetti monsters”.
Both the Nazca and adjoining Salas y Gómez Ridge are currently being considered for designation as a high seas marine protected area.
This was SOI’s third expedition this year on the Nazca and Salas y Gómez Ridges, with some 25 seamounts now explored. the previous trips in January and February documented more than 150 previously unknown species, as well as range extensions for animals not previously known to live there.
Before the expeditions 1,019 species had been known to live in this part of the Pacific but that number has now been extended beyond 1,300 and is still growing.
The findings will be sent to Ocean Census, the international alliance led by the Nippon Foundation and Nekton to accelerate the discovery and protection of ocean life.
Its researchers and hydrographers from the Centre for Coastal & Ocean Mapping / Joint Hydrographic Centre at the University of New Hampshire were present on the expedition, the latter carrying out the mapping.
“The discovery of a new seamount almost 2 miles tall – almost four times as tall as the Burj Khalifa – with a vibrant ecosystem was very exciting,” said co-chief scientist and SOI executive director Dr. Jyotika Virmani.
“Only 26% of the seafloor has been mapped to this high resolution and each expedition on Falkor brings into focus a little more of the unknown seabed and life on our home planet.”
Also on Divernet: 100 SUSPECTED NEW SPECIES FOUND DEEP OFF CHILE, 4 NEW DEEP-SEA OCTOPUS SPECIES IDENTIFIED, DEEP OCTOPUS NURSERIES ON ‘EDGE OF HUMAN IMAGINATION’, INTO THE UNDERWORLD: NEW ECOSYSTEM FOUND BENEATH HOT SMOKERS
