The National Oceanic and Atmospheric Administration (NOAA) recently conducted a deep-sea dive, which included capturing a red disk-shaped jellyfish 2,300 feet beneath the Atlantic Ocean for the first time.
Based on its characteristics, researchers who caught it on camera believe that it might belong to a still undescribed species under the genus Poralia. This taxonomic group is a currently monotypic genus that only has one recorded species, Poralia rufescens, according to the World Register of Marine Species (WoRMS). This genus has a bell-shaped top with up to 30 tentacles mixed with 15 sensory organs called rhopalia.
Aside from the red deep-sea jellyfish, the expedition also discovered other undescribed animals, including a ctenophore or a comb jelly belonging to the order Cydippida found about 4,000 feet below the surface.
Exploring the Twilight Zone
Writing for the NOAA Ocean Explorer website, NOAA Hollings Scholar Quinn L. Girasek explained her purpose for joining the expedition, which yielded extraordinary discoveries. For her summer project, she aims to better understand the abundance of organisms in the so-called Twilight Zone. Formally known as the mesopelagic zone of the middle open ocean, the Woods Hole Oceanographic Institution explains it as the layer of the world's waters between 200 to 1,000 meters (around 650 to 3,300 ft) below the surface. Her study specifically focuses on the Atlantic Ocean near the Gulf Stream and reaching the deep-scattering layer.
According to a March 2020 study in the Nature journal, the Twilight Zone is home to the largest yet least exploited fish stocks among the world's waters. It is described as the interface between the well-explored sunlit zone and the even more mysterious abyss underneath. The international team of researchers behind this study recognizes the difficulty of studying the layer yet stresses the importance of studying this part of the ocean. Since most of the waters falling into the Twilight Zone are almost pristine and are located outside any nation's jurisdiction, these waters are "of common interest and responsibility," adding that a global consensus is necessary to manage it in the years to come.
A Host of Interesting Underwater Finds
As a member of the NOAA Ocean Exploration onboard the 2021 North Atlantic Stepping Stones expedition, Girasek was tasked with annotating the dive, with her notes being included into SeaTube, an electronic database currently maintained by Ocean Networks Canada. Then, they traveled along the US East Coast, using a remotely operated vehicle (ROV) called Deep Discoverer, which is fitted with a robotic arm or a suction sampler to extract specimens from the waters of the Atlantic Ocean and into collection jars for storage and analysis.
The expedition conducted a total of 25 dives through the Deep Discoverer, with its data being used to further the understanding and distribution of deepwater habitats in the area. Girasek explains that throughout the expedition, they were able to find various animals like ctenophores (comb jellies), cnidarians (coelenterate), crustaceans, and Actinopterygii (ray-finned fishes). Another interesting find during the North Atlantic Ocean expedition is the now-viral video tagged as a "'Real-Life' Sighting of SpongeBob SquarePants and Patrick Star." The undersea footage featured a yellow glass sponge from the genus Hertwigia beside a pink poraniid starfish, resembling the main characters of the popular kids' show.
Check out more news and information on the National Oceanic and Atmospheric Administration in Science Times.