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From the University of Alaska Fairbanks:
Divers find new species in Aleutians
Fairbanks, ALASKA– There are unknown creatures lurking under the windswept islands of the Aleutians, according to a team of scientific divers from the University of Alaska Fairbanks.
This summer, while completing the second phase of a two-year broad scientific survey of the waters around the Aleutian Islands, scientists have discovered what may be three new marine organisms. This year’s dives surveyed the western region of the Aleutians, from Attu to Amila Island, while last year’s assessment covered the eastern region.
During the dives, two potentially new species of sea anemones have been discovered. Stephen Jewett, a professor of marine biology and the dive leader on the expedition, says that these are “walking” or “swimming” anemones because they move across the seafloor as they feed. While most sea anemones are anchored to the seabed, a “swimming” anemone can detach and drift with ocean currents. The size of these anemones ranges from the size of a softball to the size of a basketball.
Another new species is a kelp or brown algae that scientists have named the “Golden V Kelp” or Aureophycus aleuticus. According to Mandy Lindeberg, an algae expert with NOAA’s National Marine Fisheries Service and a member of the expedition, the kelp may represent a new genus, or even family, of the seaweed. Up to ten feet long, the kelp was discovered near thermal vents in the region of the Islands of the Four Mountains.
“Since the underwater world of the Aleutian Islands has been studied so little, new species are being discovered, even today,” said Jewett. He adds that even more new species may be revealed as samples collected during the dives continue to be analyzed.
From Deep Sea News:
An enormous sea anemone from 2500m depth on the East Pacific Rise was reported in the journal Marine Biology. The monstrous actiniarian Boloceroides daphneae is abundant on boulders, cliffs, and rocky outcrops near hydrothermal vent sites but not on them, writes author Marymegan Daly from Ohio State University. The largest living specimen she found had a column diameter of 1m, a tentacle crown of 2m diameter, and tentacles trailing an estimated 3m and more. That’s just downright dangerous. B. daphneae’s closest living relative is the comparatively diminutive Cerianthid anemone found in warmer coastal waters.
The new species has been known since 1990, but it was tough to collect, and it provides a good example of commonly encountered but largely unstudied species in the deep sea environment.
The middle of the South Pacific is as far away from land as you can possibly get. Solar irradiance is dangerously high, reaching a UV-index that is labelled ‘extreme’. There are no dust particles or inflows from the land and as a result these waters have extremely low nutrient concentrations, and thus are termed ‘ultraoligotrophic’. Chlorophyll-containing phytoplankton (minute algae) are found only at depths greater than a hundred meters, making surface South Pacific waters the clearest in the world. Due to its remoteness and enormous size — the South Pacific Gyre covers 37 million km2 (for comparison, the US cover less than 10 million km2) -, it is also one of the least studied regions on our planet: here.