The Darwin Mounds and the first specimen from British waters of the cold-water coral Lophelia pertusa

When we think of corals we think of tropical islands, white beaches and warm, clear, blue water. It may come as something of a surprise to learn that there are coral reefs lying offshore from Scotland, in the cold waters of the North Sea and North Atlantic.

The unique, and internationally important, cold-water coral reefs known as the Darwin Mounds lie 1000m below the surface of the sea in the Rockall trough. There are hundreds of mounds, each about 5m high and 100m across, covering an area of over 100 square kilometres. These spectacular reefs are currently much in the news because of the fear that they are being severely damaged by contemporary fishing activities.

Cold water coral reef. Lophelia, sea urchinand squat lobster
From: http://docs.lib.noaa.gov

The mounds consist mainly of sand covered in colonies of the cold-water coral Lophelia pertusa and coral debris. The corals themselves provide a habitat for a variety of other invertebrates, such as sponges, as well as for fishes.

The mounds were only discovered in May 1998 during surveys by the oil industry. However, we have known about cold-water corals for much longer than that. The first recorded specimen Lophelia pertusa from British waters is one of the treasures of the University of Aberdeen's Zoology Museum.

Lophelia pertusa
Photograph Martyn L Gorman

During the early nineteenth century, local fishermen obtained four specimens of the deep-water coral from Scottish waters. Two were from off the Shetland Islands and two from the Inner Hebrides.

The specimen on display in Aberdeen is one of the four. Weighing 2.48 kg, it was brought up in 1845, from a depth of around 150 metres between the islands of Rum and Eigg. In March 1846, the coral was exhibited by Professor J. Fleming at a meeting of the Royal Society of Edinburgh and was then deposited in the museum of King's College, Aberdeen.

The British Museum (Natural History) collections contain a small, 9-gram specimen presented by Fleming in 1849. Their small specimen fits the Aberdeen one quite perfectly, at the point coloured red, indicating that it was broken off sometime between 1845 and 1849.

For further details see:

WILSON, J.B., 1979. The first recorded specimens of the deep-water coral Lophelia pertusa (Linnaeus 1758) from British waters. Bulletin of the British Museum (Natural History) Zoology Series, 36, pp. 209-215.