Coral reef discovered off Greenland
Coral from the newly discovered reef off Greenland
The first ever Greenlandic reef is located in southwest Greenland and
was formed by cold-water corals with hard limestone skeletons. There are
several species of coral in Greenland, but this is the first time that
an actual reef has been found.
In the tropics, reefs are popular tourist destination for divers, but
there is little prospect of Greenland becoming a similar diving hotspot.
The newly discovered living reef is located off Cape Desolation south
of Ivittuut, and lies at a depth of 900 meters in a spot with very
strong currents, making it difficult to reach. This also means that so
far little is known about the reef itself and what lives on it
The reef was discovered by accident when a Canadian research vessel
needed to take some water samples. When the ship sent the measuring
instruments down to a depth of 900 meters, they came back up completely
smashed. Fortunately there were several pieces of broken coral branches
on the instrument that showed what was responsible.
"At first the researchers were swearing and cursing at the smashed
equipment and were just about to throw the pieces of coral back into the
sea, when luckily they realized what they were holding," says PhD
student Helle Jørgensbye, DTU Aqua, who does research into life at the
bottom of the west Greenland waters.
The first photos
Another Canadian research vessel returned to the site last fall to try
and lower a camera down onto the reef to explore it close up. The coral
reef is on the continental shelf itself where it is very steep and where
there are strong currents.
"We got some photos eventually, although we almost lost them at the
bottom of the ocean as the camera got stuck fast somewhere down in the
depths. Luckily we managed to get it loose again and back up to the
surface," says Helle Jørgensbye.
"It's been known for many years that coral reefs have existed in Norway
and Iceland and there is a lot of research on the Norwegian reefs, but
not a great deal is known about Greenland. In Norway, the reefs grow up
to 30 meters high and several kilometers long. The great Norwegian reefs
are over 8,000 years old, which means that they probably started to
grow after the ice disappeared after the last ice age. The Greenlandic
reef is probably smaller, and we still don't know how old it is," says
Helle Jørgensbye, expressing the hope that at some point this will be
investigated more closely.
According to Helle Jørgensbye, finding a coral reef in southern
Greenland was not entirely unexpected:
"There are coral reefs in the countries around Greenland and the effect
of the Gulf Stream, which reaches the west coast, means that the sea
temperature get up to about 4 degrees, which is warm enough for corals
to thrive. In addition to the, for Greenland, comparatively warm
temperature, a coral reef also needs strong currents. Both these
conditions can be found in southern Greenland," she says.
Coral reefs are important areas for fish because it provides masses of
food and lots of hiding places for fish fry. The Greenlandic reef is
formed from Lophelia stoney corals. Other species of coral are also
found in many parts of the west coast. However, they are all
'stand-alone' corals and do not form reefs. The identification of the
Lophelia specimen was carried out by Professor Ole Tendal from Denmark's
Natural History Museum.
Cold Water Corals
Normally, coral reefs are associated with the tropics, but they are also
found in cold waters. While the tropical coral reefs depend on light to
survive, cold-water coral reefs live in total darkness, at depths the
sun's rays never penetrate. Nevertheless, they have many colorful
residents and many different kinds of organisms living in them.
Coral reefs are built up of thousands of small coral animals that live
in a large colony which forms a common limestone skeleton. While hot
water corals obtain some of the energy they need to grow from the
light-dependent green algae which live in the corals, cold water coral
get all their nourishment from small animals, which they catch. Thus,
they are not dependent on light and can live in very deep water
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