Darwin Mounds
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Darwin Mounds is a large field of undersea sand mounds situated off the north west coast of
Scotland Scotland (, ) is a Countries of the United Kingdom, country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...
that were first discovered in May 1998. They provide a unique habitat for ancient
deep water coral The habitat of deep-water corals, also known as cold-water corals, extends to deeper, darker parts of the oceans than tropical corals, ranging from near the surface to the abyss, beyond where water temperatures may be as cold as . Deep-water cor ...
reefs and were found using remote sensing techniques during surveys funded by the oil industry and steered by the joint industry and United Kingdom government group the Atlantic Frontier Environment Network (AFEN) (Masson and Jacobs 1998). The mounds were named after the
research vessel A research vessel (RV or R/V) is a ship or boat designed, modified, or equipped to carry out research at sea. Research vessels carry out a number of roles. Some of these roles can be combined into a single vessel but others require a dedicated ...
, itself named for the eminent naturalist and
evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
ary theorist
Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended ...
. The mounds are about below the surface of the
North Atlantic ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe an ...
, approximately north-west of Cape Wrath, the north-west tip of mainland Scotland. There are hundreds of mounds in the field, which in total cover approximately . Individual mounds are typically circular, up to high and wide. Most of the mounds are also distinguished by the presence of an additional feature referred to as a 'tail'. The tails are of a variable extent and may merge with others, but are generally a teardrop shape and are orientated south-west of the mound. The mound-tail feature of the Darwin Mounds is apparently unique globally.Biogenic reefs - cold water corals
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Composition

The mounds are mostly sand, currently interpreted as "
sand volcano Sand boils or sand volcanoes occur when water under pressure wells up through a bed of sand. The water looks like it is boiling up from the bed of sand, hence the name. Sand volcano A sand volcano or sand blow is a cone of sand formed by the ...
es". These features are caused when fluidised sand "de-waters" and the fluid bubbles up through the sand, pushing the sediment up into a cone shape. Sand volcanoes are common in the Devonian fossil record in UK, and in seismically active areas of the planet. In this case, tectonic activity is unlikely; some form of slumping on the south-west side of the undersea (Wyville-Thomson) Ridge being a more likely cause. The tops of the mounds have living stands of Lophelia and blocky rubble (interpreted as coral debris). The mounds provide one of the largest known northerly cold-water habitats for
coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...
species. The mounds are also unusual in that Lophelia pertusa, a cold water coral, appears to be growing on sand rather than a hard substratum. Prior to research on the mounds in 2000, it was thought that Lophelia required a hard substratum for attachment. The deep-water coral systems on the mounds are especially fragile. Unlike shallow-water
coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. C ...
s, they are not adapted to cope with minor disturbances such as wave action. The mounds also support significant populations of the xenophyophore ''
Syringammina fragilissima ''Syringammina'' is a xenophyophore found off the coast of Scotland, near Rockall. It is one of the largest single-celled organisms known, at up to across. It was first described in 1882 by the oceanographer John Murray, after being discovered ...
''. This is a giant single-celled organism (a protozoan) that is widespread in deep waters, but occurs in particularly high densities on the mounds and the tails. Individual xenophyophores can grow to be larger than and are often very fragile. The corals themselves provide a habitat for a wide diversity of other marine life including
sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...
s,
worm Worms are many different distantly related bilateral animals that typically have a long cylindrical tube-like body, no limbs, and no eyes (though not always). Worms vary in size from microscopic to over in length for marine polychaete wo ...
s,
crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...
s and molluscs. Among these starfish, sea urchins and crabs. Various fish have been observed, including blue ling, roundnose grenadier, and the orange roughy.


Conservation efforts

On 23 October 2001, UK Minister
Margaret Beckett Dame Margaret Mary Beckett (''née'' Jackson; born 15 January 1943) is a British politician who has served as the Member of Parliament (MP) for Derby South since 1983. A member of the Labour Party, she became Britain's first female Foreign S ...
made a commitment at WWF's Oceans Recovery Summit in
Edinburgh Edinburgh ( ; gd, Dùn Èideann ) is the capital city of Scotland and one of its 32 council areas. Historically part of the county of Midlothian (interchangeably Edinburghshire before 1921), it is located in Lothian on the southern shore of t ...
to protect the Darwin Mounds. The summit launched the Edinburgh Declaration, targeting politicians and marine stakeholders alike to sign up to action to safeguard the seas. Deep water
bottom trawling Bottom trawling is trawling (towing a trawl, which is a fishing net) along the seafloor. It is also referred to as "dragging". The scientific community divides bottom trawling into benthic trawling and demersal trawling. Benthic trawling is towing ...
had been occurring in the area, with nets as heavy as one tonne dragged across the sea floor. Researcher Jason Hall-Spencer of the University of Glasgow had found pieces of coral at least 4,500 years old in the nets of trawlers operating off the coast of Ireland and Scotland. Pieces of coral up to were found in the nets of French trawling vessels that had been scraping the seabed down. It is known that much coral was destroyed by these nets and the mounds themselves in some areas were found to be scraped and flattened. The mounds are ancient structures, and this damage is permanent. After the discovery of the mounds, three well-documented surveys of the area were undertaken, one in June 1998 (Bett 1999), August 1999 (Bett & Jacobs 2000,) and twice during summer 2000 (B. Bett, pers. comm.). Instruments deployed during the studies included
side-scan sonar Side-scan sonar (also sometimes called side scan sonar, sidescan sonar, side imaging sonar, side-imaging sonar and bottom classification sonar) is a category of sonar system that is used to efficiently create an image of large areas of the sea ...
, stills and video cameras and piston corers. However, the entirety of what was lost to heavy-netted fishing trawlers remains unknown. On 22 March 2004 EU Fisheries Ministers in Brussels agreed to give permanent protection to the United Kingdom's unique cold-water coral reefs, recognising the Darwin Mounds as an important habitat. In 2004 deep-water bottom trawling in the area was made illegal.


See also

*
List of reefs This is an incomplete list of notable reefs. Reefs See also *Fringing reef *Recreational dive sites *Recreational diving *Southeast Asian coral reefs *''The Structure and Distribution of Coral Reefs ''The Structure and Distribution of Cor ...


References


External links


"Biogenic reefs - cold water corals"
Joint Nature Conservation Committee, U.K. government, retrieved 8 December 2007
"Trawler ban to protect reefs
''BBC News'', 20 August 2003 {{coord, 59, 45, N, 7, 13, W, region:GB-SCT_type:landmark_source:dewiki, display=title 1998 in science 1998 in Scotland Coral reefs Landforms of Highland (council area) Physical oceanography Reefs of the Atlantic Ocean Reefs of Scotland Scottish coast