May 25, 2016
This week, the scientific journal Marine Biodiversity published a study describing the largest sponge known in the world , found at a depth of 7,000 feet within Papahānaumokuākea Marine National Monument. The sponge was close to 12 feet long and 7 feet wide, comparable in size to a minivan.
The sponge was documented during the 2015 Hohonu Moana: Exploring Deepwaters off Hawaiʻi expedition aboard NOAA Ship Okeanos Explorer while exploring deep-water habitats in the Monument using remotely operated vehicles (ROV) at depths ranging between 2,300–16,000 feet.
“The largest portion of our planet lies in deep waters, the vast majority of which has never been explored,” said Papahānaumokuākea research specialist Daniel Wagner, Ph.D, science lead of the expedition with NOAA’s Office of National Marine Sanctuaries. “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.”
While not much is known about the lifespan of sponges, some massive species found in shallow waters (<100 feet) are estimated to live more than 2,300 years.
The sponge was captured on video during an ROV dive on a ridge extending from a seamount south of Pearl and Hermes Atoll within Papahānaumokuākea. Scientists from NOAA’s Office of National Marine Sanctuaries, NOAA’s Office for Exploration and Research and the University of Hawaiʻi described the sponge after a year of study.
The 2015 Hohonu Moana expedition is part of the three-year Campaign to Address the Pacific monument Science, Technology, and Ocean NEeds (CAPSTONE), a foundational science effort focused on deepwater areas of U.S. marine protected areas in the central and western Pacific.