David, i and probably many other Conchlers would have missed this incredible
article about deep-sea corals, which of course is definitely mollusc-related,
since who knows how many new species will turn up once these amazing endangered
ecosytems are properly explored!!

-Ross.

 --David Kirsh

"Deep Peril for Deep-Sea Corals" - New York Times, Sept. 19, 2000.
by Andrew C. Revkin

    For nine miles along a submerged ridge, the corals rise in lumpy hillocks
that spread out 100 yards or more, resembling heaped scoops of rainbow sherbet
and Neapolitan ice cream. The mounds, some 100 feet tall, sprout delicate
treelike gorgonians that sift currents for a plankton meal. Fish, worms and
other creatures dart or crawl in every crevice.
    This description could apply to thousands of coral reefs in shallow,
sun-streaked tropical waters from Australia to the Bahamas. But this is the Sula
Ridge, 1000 feet down in frigid darkness on the continental shelf 100 miles off
Norway's coast.
    The pinks, yellows, oranges and other colors are apparent only under the
blazing artificial light beamed from remote-controlled submersibles wielding
video cameras. Absent such intrusions, this is a world of utter blackness.
    Nearly 250 years ago, Scandinavian scientists, including Linnaeus, first
described some of these cold-water corals, but only from bits and pieces pulled
up in fishing nets or on hooks. Only in the last decade or so, as research
sunbmarines and robotic devices have become widely used, has the diversity and
extent of these banks and reefs become apparent.
    Marine biologists now say that deep-sea corals and attendant organisms
easily rival tropical reefs in their diversity--and their fragility.
    The same scientists who have neen mapping these ecosystems for the first
time in waters off Alaska, eastern Canada, Northern Europe, Australia and New
Zealand have simultaneously been chronicling wide-spread damage from  fleets of
trawlers with gear that has been dropped ever deeper as fisheries in shallower
waters are depleted.
    "On sonar you can see the trawl tracks, like linear scars in the bottom,"
said Dr. Jan Helge Fosse, a marine ecologist at the Norwegian Institute of
Marine Research.
    Often, it has been commercial hook-and-line fishermen who have alerted
scientists to the damage from the factory-scale fishing boats, which they see as
a threat to their catch. That was the case in Nova Scotia, where reports
surfaced several years ago of pairs of trawlers towing bottom-dragging cables
between them to systematically topple forests of treelike Paragorgia corals so
nothing would snag their gear on later passes.
    Biologists have become alarmed but the extent of damage, with surveys in
Norway indicating that a third to half of the charted deep reefs show some harm
from fishing. This is particularly distressing, scientists say, not only because
it could take centuries for the slow-growing corals to regenerate, but also
because they contain clues to past climate and ocean-temperature shifts.
    Variations in their microscopic growth rings and chemical composition
provide the deep-sea equivalent of the climate record in tree rings, and
scientists are just beginning to assess this newfound trove of data, said Dr.
Michael Risk a geologist at McMaster University In Hamilton, Ontario, who
recently published a paper in Nature on the temperature data in a coral sample.
    "The weak point always in every climate model is that we don't know what
happens in the oceans, and here we've got this benthic tape recorder," Dr. Risk
said. "The problem is, it's being wrecked."

    He said a fisherman provided an early hint of the potential locked in the
corals. "He hopped a fence at a wharf a couple years ago, went to a trawler and
grabbed a specimen out of their net," he said. "He shipped it to me and it
turned out it was 500 years old. That fisherman started getting death threats.
And that piece was one-and-a-half inches in diameter. We hear stories of corals
as big around as your leg. Some of these things may live thousands of years."
    At the first international conference on deep sea corals, held this summer
in Halifax, Nova Scotia, nearly 100 biologists and geologists compared notes and
issued a statement calling for the expansion of marine protected areas to shield
deep corals. So far only Norway and Australia have begun to do so.
    "Most scientists are rather cautious types, but at the conference there was
a very strong feeling that we have to step out from the closet of science and do
something to protect them," said Dr. Martin Willison, a biologist at Dalhousie
University in Halifax, who helped organize the conference.
    The joint statement said, "It is essential that existing national laws and
international conventions for the protection of biodiversity and the regulation
of fisheries be extended to cover these unique and vulnerable deep-water habitats."
    In a recent interview, Dr. Willison marveled at how knowledge of deep corals
had exploded in the last couple of decades. Scientists have now mapped them in
the Gulf of Mexico and Mediterranean, along continental shelves on both sides of
the Pacific and Atlantic, and from Tasmania to the Arctic.
    "I can get under my belt the idea of coral reefs in northern waters," Dr.
Willison said, "but to think of them above the Arctic Circle was really quite spectacular."
    Shallow-water corals are colonies of two organisms--a plankton-eating polyp
and sun-dependent algae called zooxanthellae. Unlike them, the deep corals have
only the carnivorous polyps, which use sticky mucus or stinging arms to capture
zooplankton meals. This trait has allowed them, over tens of milions of years,
to break free of dependence on light.
    Fossil evidence show some similar kinds of deep-sea mounds dating from 400
million years ago. geologists say. Reefs in different places are dominated by
different forms. Bulbous colonies of Lophelia pertusa are typical in Northern
Europe. The sea bottom off Nova Scotia and eastern Maine is more likely to hold
forests of treelike pink Paragorgia corals, nicknamed "bubble gum tree" by
Canadian fishermen, and Primnoa, a genus that has finer branches and is more bushlike.
    Generally, scientists say, the deep corals seem to thrive in places where a
hard rock bottom protrudes from the silt, providing a firm anchor, and a place
for plankton to thrive--sites like the waters off the Bay of Fundy or areas
around sea mounts, submerged mountains whose peaks reach within a thousand feet
or so of the surface. They also tend to grow in places with strong, turbulent
bottom currents, like ridges on the continental shelf off Norway that were left
behind by the retreating glaciers of the last ice age. Sula Ridge off Norway is
one such formation.     One theory is that the corals are binge eaters, relying
on a spring rain of zooplankton from the surface that is then swept along the
bottom by strong currents, said Dr. Andre Freiwald, a geologist at the
University of Tubingen in Germany, who last week began a three-week trip using
side-scan sonar to map corals in waters from Norway to Spain.
    But there are other theories, Dr. Martin Hovland, a marine geologists, who
surveys pipeline routes from Statoil, Norway's state-owned oil company, first
mapped some of the country's extensive offshore corals nearly 20 years ago. He
said many of the mounds seemed to be over areas of sea floor seeping
hydrocarbons, which could be providing sustenance for plankton and creating a
food chain supporting the deep reefs.
    The diversity of life in the interstices of the corals mounds is dizzying,
and just beginning to be appreciated. Several years ago, Andreas Jensen and Rune
Frederiksen, from the Zoological Museum of the University of Copenhagen,
dissected 40 pounds of coral hunks retrieved from a reef near the Faroe Islands,
east of Iceland. They counted 4626 orgainisms belonging to 256 species, with 42
other species in loose coral rubble that came up with the pieces.
    Nearly 100 species had never been recorded from that region before. And when
the scientists compared the creatures with those from coral samples taken from
reefs in Norway and Bay of Biscay, there were only a few overlaps, indicating
just how variegated this deep-sea quilt is.
    Surprises continue to pop up. At the Halifax conference, Sanford Atwood, a
longtime hook-and-line fisherman from The Hawk, a Nova Scotia village, showed
some visiting scientists a few of the small, pillow-shaped corals he had
collected. They were eight or nine inches across and were called "hard hats" by
the locals because of their shape.
    "Some experts there said the chance of hauling that up where you said you
did is the same chance as finding something in our forest that belongs in a rain
forest," said Mr. Atwood, who recently shifted to lobster fishing because of
declines in stocks of haddock, cod and other fin fish. He said the destruction
from trawling could well be contributing to the drop in fish populations.
    At the Hell Hole, a spot favored for generations by Nova Scotia long-liners,
he said, the corals were always a well-known feature of the bottom. But now they
appear to be mostly knocked down, he said, and the fishing suffers.
    "I'm not an expert when it comes to science, but I do know how to go fishing
and what fish depend on," he said, adding that it made no sense to let the
destruction of the corals ontinue. "We take and take and take but never give.
It's about time we did something for the ocean."