Four kilometres below the surface of the South Atlantic, off the coast of Argentina, a remotely operated vehicle descended into a submarine canyon that had never been visited by humans before — and found both a slice of deep-sea biology that science has no names for yet and the unmistakable residue of the surface world above it.
The expedition, run from the research vessel Falkor(too) under the identifier FKt250712, used the Schmidt Ocean Institute’s ROV SuBastian to explore the Mar del Plata Submarine Canyon to depths approaching 3,820 metres. According to Oceanographic Magazine’s report on the findings, published on 17 September 2026, the international team on the cruise documented roughly 40 species suspected to be new to science, alongside a striking inventory of human-made debris. The findings have now been written up in a peer-reviewed study in PLOS One.
The biological haul is what drew the team to the canyon in the first place. Submarine canyons like this one act as conduits for organic material sinking from the productive surface waters above, and that concentration of food tends to support richer and more unusual communities than the surrounding abyssal plain. The 17 ROV dives produced enough unfamiliar specimens that the researchers are still in the early stages of formally describing them — Daily Galaxy’s write-up of the study notes that the ~40 new species are documented across the dive footage and collected samples, with taxonomic work to follow. For a single expedition, that is a remarkable yield, and it underscores how poorly sampled most of the deep ocean remains.
What makes the same dives scientifically uncomfortable is what else was sitting on the seafloor. Across 10 of the 17 dives, the team logged 29 identifiable pieces of human-made litter — 27 of them plastic — at depths ranging from shallow down to nearly four kilometres. According to Oceanographic Magazine, the inventory included fishing gear and a lone boot, and Daily Galaxy’s account highlights a particularly pointed find: an instant noodle package photographed at 1,920 metres depth, resting on sediment that almost certainly had never been disturbed by a human being before the ROV’s lights came on. The objects are individually mundane; collectively, in a canyon that has only just been reached for the first time, they read as a timestamp.
Plastic in the deep sea is not a new observation — researchers have been documenting it in abyssal sediments and along hadal trenches for years — but the canyon context sharpens the usual finding. These are not the central gyres where floating debris tends to accumulate, nor are they the continental shelves that receive the bulk of riverine input. The Mar del Plata Canyon is steep, narrow, and effectively isolated from the routes most plastic surveys describe, which makes the litter inventory a more direct read on what the overlying water column is actually delivering downward. A package of instant noodles does not get to 1,920 metres on its own; it gets there because something denser than the plastic carried it that far, and once it lands in a canyon, it is unlikely to leave.
That same geometry is what makes the biology and the litter findings feel like a single story rather than two parallel ones. The canyon concentrates life precisely because it concentrates whatever flows down from above — nutrients, sediment, and, evidently, the byproducts of a consumer economy on the surface. The ROV did not set out to look for litter; it logged what was there, and what was there in numbers was plastic. The deeper lesson of an expedition like FKt250712 is not that the deep sea is pristine or that it is ruined, but that it is genuinely both at once, in the same frame, on the same dive.
The taxonomic work on the ~40 putative new species will take years. The litter, once catalogued, does not need describing.