A deep-sea expedition dating back to 2015 led to the discovery of an extremely large sea sponge the size of a minivan, making it the largest ever recorded. The unique sea creature was discovered near Hawaii 7,000 feet below the surface, and since its discovery, the National Oceanic and Atmospheric Administration (NOAA) has been examining it closely.
"The largest portion of our planet lies in deep waters, the vast majority of which has never been explored," said Daniel Wagner of the NOAA and first author of the study. "Finding such an enormous and presumably old sponge emphasizes how much can be learned from studying deep and pristine environments such as those found in the remote Papahānaumokuākea Marine National Monument."
Extremely large sea sponges are not uncommon, and numerous different types of these creatures serve important ecological functions in the ecosystems that they inhabit, including providing habitats for other smaller creatures.
The newly discovered Hawaiian sea sponge is more than 11 feet long, 6.6 feet in height and nearly five feet wide.
Sea sponges are capable of growing to extremely large sizes, and Wagner believes that the sponge in question "is likely a very old sponge on the order of century to millennia." However, exact age determination is difficult because "sponges don't have things like growth rings that can be used to estimate age."
The team discovered the sponge during an expedition on the R/V Okeanos Explorer using remote-controlled diving vehicles (ROV), which allowed them to explore the deepest areas of the sea around the Northwestern Hawaiian Islands.
The discovery provides researchers with more reason to continue investing in and using ROV for deep-sea exploration.
"The finding of such a large organism as that reported here highlights the value of using deep-diving technologies in surveying the deepest parts of our oceans, which remain largely unexplored," the authors wrote.
Furthermore, the discovery highlights the need for conservation efforts in the area.
"The finding of such an enormous and presumably old sponge inside the Papahanaumokuakea Marine National Monument underscores the need to protect this area using the highest conservation measures available," the authors wrote.
The findings were published May 24 in Marine Biodiversity.
