Dive 18: Schumann Seamount
September 24, 2017
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Dive 18: Mega Sponge

This giant species of sponge had only ever been seen twice before, both times in the Northwestern Hawaiian Islands. To see it here in the Musicians Seamounts at Schumann Seamount indicates a connection between the two regions. This particular sponge measured over four meters (12 feet) long. Video courtesy of the NOAA Office of Ocean Exploration and Research, Deep-Sea Symphony: Exploring the Musicians Seamounts. Download (mp4, 33.7 MB)

Dive 18: The Little Dragon

While exploring on Schumann Seamount at a depth of ~2,100 meters (6,890 feet), the team encountered this halosaur, belonging to the genus Aldrovandia, as evidenced by the lack of scales on its nose. Video courtesy of the NOAA Office of Ocean Exploration and Research, Deep-Sea Symphony: Exploring the Musicians Seamounts. Download (mp4, 24.1 MB)

While exploring Schumann Seamount, the team discovered yet another high-density coral community! Remotely operated vehicle Deep Discoverer (D2) arrived on bottom at 2,311 meters (7,582 feet) depth on a flat sedimented plain with a gravelly surface dotted with isolated boulders. Some of the first biological observations included bamboo coral with “volcano polyps,” black coral, glass sponges, benthic jellyfish, a sea star predating on a coral tree, and a pair of unusual urchins with soft spines that were also observed on previous dives. Soon an oasis of life appeared in the form of dense coral fans hosted by a big isolated boulders. The seafloor transitioned into a talus slope mostly consisting of small gravelly material and a number of biological observations followed, including a large dead sponge toppled over presumably after outgrowing its rock base, parazoanthids overgrowing a pink coral, a primnoid coral with a piece of marine debris caught in its branches, a Caunacops sp. in the anglerfish family, and a halosaur. Soon after, D2 came across a giant ribbon-like sponge resembling a folded blanket that measured nearly four meters in length. This sponge, Lanuginellidae “ruffles,” has been seen twice before in the Northwestern Hawaiian Islands and a piece of this sponge was collected as a paratype to help in the description of this new species. Seeing this rare sponge here in the Musicians Seamounts may be an indication of connectivity between the two island chains.