Unidentified deep-sea creatures called "blue slime" recently puzzled scientists who spotted these mysterious patches on the seabed.
During the live stream of the expedition, team members discussed what the strange things could be, but none of the researchers could come up with a definitive answer.
Scientists who controlled a remotely operated vehicle (ROV) near the sea floor around St. Croix were seen on August 30 by several blue, slimy creatures.
The mysterious "blobs" were discovered standing motionless on the sea floor somewhere around 611 meters below the surface.
The researchers operated the ROV from the National Oceanic and Atmospheric Administration (NOAA) research vessel Okeanos Explorer, which has spent the past four months surveying parts of the North Atlantic as part of NOAA's Voyage to the Ridge 2022 survey series.
As with every dive during these expeditions, the footage was streamed live by NOAA for marine enthusiasts around the world to enjoy.
During the live broadcast, researchers spotted and zoomed in on one of the strange blue creatures and began to discuss what it could be.
Some observers have noted that it is likely either a soft coral or a sponge, and potentially even a mantle—gelatinous marine invertebrate sometimes called sea jets.
The team suggested a number of potential nicknames, including "bumpy blue thing", "blue biomass" and "blue slime".
The members of the expedition could only agree on what the mysterious creature was not: "All I can tell you is that it's not a rock, but that's all I know," joked one researcher.
The team will now begin the lengthy process of trying to identify the mysterious blue creature. In a live broadcast, the researchers said they will send pictures and videos to coral and sponge experts to see if they can identify the blue creatures.