Ocean Explorers Find Seamount Thriving Thousands of Feet Underwater With Rare ‘Casper’ Octopus
A remote-controlled deep-sea robot detected groves of sponge gardens and ancient coral submerged thousands of feet under the Pacific Ocean. This hidden ecosystem was videoed for the first time thriving on a newfound underwater mountain—or seamount—off the western coast of South America.
On an oceanographic voyage, a team of researchers led by the Schmidt Ocean Institute, founded by Eric Schmidt, announced they had discovered this seamount along an underwater chain of mountains called the Nazca Ridge, 900 miles off the coast of Chile.
The seamount, one of several recent discoveries the team has made, covers approximately 43 square miles. It lies at a depth of about 2.5 miles at its base, and its summit is 1.9 miles high. Its highest point measures 0.6 miles deep below the waves.
Aboard Research Vessel Falkor (too), the scientists deployed a remotely operated vehicle (ROV) to explore and map the seamount in high resolution. The ROV, dubbed SuBastian, was equipped with multibeam echosounder sensors and found that the sponge gardens and ancient coral growing on the seamount supported a bountiful deep-sea ecosystem.
The exploration would be a 28-day survey of the mountainous Nazca Ridge, which runs parallel to the Salas y Gómez Ridge in the Southeast Pacific. In fact, this survey was one of several related scientific voyages to the area, during which the team previously laid claim to many first-time discoveries.
Besides this new seamount biome, there were numerous other groundbreaking finds. In a previous dive, the scientists discovered another seamount with a pristine coral garden about a half square mile in size, roughly as big as three tennis courts.
They sighted sea animals that had never been videoed live before, including one species called the Promachoteuthis squid, which until recently had only been found dead in nets. They found a curious animal that had never been seen in the Southern Pacific: the adorable-looking and aptly named Casper octopus.
Among other notable sea creatures discovered were two rare Bathyphysa siphonophores, a species colorfully nicknamed the flying spaghetti monster, which were video recorded during the expeditions.
The list goes on. A large bamboo coral holding benthic ctenophores, barnacles, a sea star, and ophiuroids was documented on one of the hundreds of dives the team undertook during the expeditions.
One of the big highlights of their research has been the identification of new species. The latest expedition, the third in the study, collected 20 previously unknown species while the two previous voyages, in January and February, documented 150 in all.
"Upon concluding our third expedition to the region, we've explored around 25 seamounts on the Nazca and Salas y Gómez Ridges," marine technician Tomer Ketter said in a Schmidt Ocean Institute press release. "Our findings highlight the remarkable diversity of these ecosystems, while simultaneously revealing the gaps in our understanding of how the seamount ecosystems are interconnected."
Aboard the research vessel, Ketter supervised mission control, monitoring the ROV alongside Michael Rae and Erin Easton. Another scientist onboard, Alex Rogers, noted the incredible biological diversity these underwater mountains offer.
"The seamounts of the Southeastern Pacific host remarkable biological diversity, with species found nowhere else to date," Rogers said. "The work our taxonomists have conducted aboard Falkor (too), supported by the Schmidt Ocean Institute team, will significantly enhance our understanding of the distribution of remarkable life forms on these underwater mountains, including several that have never before been mapped or seen by human eyes."
The thriving, 2.5-mile-high seamount has managed to inspire the imaginations of some scientists. Schmidt Ocean Institute executive director Jyotika Virmani called it "very exciting" to have discovered "a new seamount almost 2 miles tall—almost four times as tall as the Burj Khalifa—with a vibrant ecosystem."
Invoking curiosity, she added: "Only 26 percent of the seafloor has been mapped to this high resolution and each expedition on Falkor (too) brings into focus a little more of the unknown seabed and life on our home planet."
