Plan for More Deep Seafloor Observations Might Find Something “Weird”
Only 0.001% of the deep seafloor has been visually observed despite covering more than half of the planet’s surface.
On April 1, the Ocean Discovery League set out to build on that 0.001% with the launch of the Global Deep Sea Exploration Goals, an international effort to visually explore 10,000 strategically selected locations across the deep seafloor.
The target locations were selected with the aim of providing a representative picture of deep seafloor environmental diversity.
What might be found? Perhaps something weirder than the “forest of the weird.”
On July 25, 2017, scientists onboard NOAA’s Okeanos Explorer observed a tiny part of the 0.001% and found what they dubbed the “forest of the weird” at a depth of around 2,442 meters in waters off the Johnston Atoll, roughly 750–825 nautical miles southwest of Honolulu, Hawaii.
The dive log on the day of the discovery states:
“The bottom was characterized by large boulders, cemented basalt, and rocks with a heavy manganese crust and light dusting of sediment. The dive track going upslope was on a sustained community of sponges that also included deep-sea octocorals and associated invertebrates. When Deep Discoverer reached a ridge, the current changed. Here, the community was composed almost exclusively of glass sponges and their diversity increased dramatically – some hexactinellids were unusually large.
“Many sponges had their concave sides directed towards the current, and a new sponge species in the genus Poliopogon was observed. Dead glass sponge skeletons were also present, sometimes in high abundance. Colonial octocorals were the second most abundant group observed and included members of the chrysogorgiids, the primnoids, coralliids, and five or six species of bamboo corals – one whip was nearly five meters tall.
“There were a few black corals, “stoloniferous” zoanthids, and at least two species of anemones – several small individuals covered a primnoid coral. Other notable cnidarians included small hydroids, a small benthic ctenophore on a glass sponge, a four-armed narcomedusae, and a small jellyfish.
“Relatively few observations of echinoderms were made during this dive and included a single stalked crinoid with hydroids on its stalk, feather stars (one with eulimid snails parasitizing it), Lophaster, a solasterid sea-star, a filter-feeding brisingid, one urchin, and two sea cucumber species.
“Numerous ophiuroid commensals were present on corals. Other organisms observed included shrimp, squat lobsters, small swimming polychaetes, worms of unknown affinity, and small lyrate-shaped organisms which were not identified. We saw no fish today.”