The highly diverse bottom fauna

On the seabed off Sisimiut, among redbrown algae and small purple sponges, a polychaete worm hunts for prey. The small, striped animal belongs to a group of bristle worms with relatively hard plate sections on their backs, which has given them the name scalebacks.
ALEXANDER BENEDIK/CATERS NEWS/RITZAU SCANPIX, 2017

Bottom-dwelling animals constitute some of the most diverse species of marine fauna. The most common invertebrates stem from groups of mussels, worms, sea urchins, ascidians and crustaceans. Fish from the group of flatfish and lumpfish species are also part of the bottom fauna. Greenland’s marine areas of about 2.2 million km² have an immensely diverse bottom fauna, however, systematic studies have only been carried out in a few areas, and it is believed that the approximately 2,100 different species described so far only represent a fraction of the bottom fauna.

The deep-water shrimp is found in deep water (over 50 m) and soft bottom from Uummannarsuaq (Cape Farewell) to Qimusseriarsuaq (Melville Bay) and along most of the East Greenland coast. The shrimp has a peculiar life form as it changes sex from male to female when fully grown. It feeds on dead organic matter, algae and small worms, and often embarks on nocturnal expeditions up through the water column in search of plankton. Shrimp fishery began in the 1930s by Sisimiut, but it was not until the 1950s that the inshore fishery in Qeqertarsuup Tunua gained commercial importance. With the decline in cod in the 1970s, offshore shrimp fishery also increased in both West and East Greenland, and since the 1980s, fishing for the deep-water shrimp has been the most economically important type of fishery in Greenland. Of the two other bottomdwelling species caught in small numbers in West Greenland, the snow crab is the most important, and the scallop is currently of no importance. Other common species in the bottom fauna include mussels, starfish, sea urchins, brittle stars and a number of other crustaceans.

The Davis Strait has large populations soft corals and sea pens; off Nuuk, at a depth of 300 to 600 metres, there is an area of about 500 km² with a high concentration of soft corals, and in East Greenland there are populations of large 2‑3 m high sea fans, which are also a type of coral. These areas densely populated with corals are also habitats for a number of species of starfish, shrimps, snails, sea anemones, sponges, crabs, bottom-dwelling fish, sea lilies and basket stars. Since these areas are of particular biological importance, restrictions on trawling have been introduced in some of the areas with high concentrations of corals.

Further reading