Darwin Mounds facts for kids
The Darwin Mounds are a huge area of sand hills found deep under the sea. They are located off the northwest coast of Scotland. Scientists first discovered them in May 1998. These mounds are a special home for very old deep water coral reefs. They were found using special tools that can "see" underwater. These surveys were paid for by oil companies and a group called the Atlantic Frontier Environment Network (AFEN). The mounds got their name from the research vessel (a type of ship) that found them. That ship was named after Charles Darwin, a famous scientist who studied nature and evolution.
The mounds are about 1,000 metres (3,300 ft) deep in the Atlantic Ocean. They are located about 100 nautical miles (190 km) northwest of Cape Wrath, which is the northwest tip of mainland Scotland. There are hundreds of these mounds. Together, they cover an area of about 100 square kilometres (39 sq mi). Each mound is usually round. They can be up to 5 metres (16 ft) high and 100 metres (330 ft) wide. Most mounds also have a unique "tail" feature. These tails vary in size and can sometimes join with other tails. They are usually shaped like a teardrop and point southwest from the mound. This mound-tail shape is very rare and has not been seen anywhere else in the world.
What are the Mounds Made Of?
The Darwin Mounds are mostly made of sand. Scientists think they are like "sand volcanoes." This happens when sand that is full of water releases the water. The water bubbles up through the sand, pushing the sand into a cone shape. Sand volcanoes are common in old rock records in the UK. They also appear in areas of the world where there is a lot of earthquake activity. However, earthquakes are not likely the cause here. Instead, it's more likely that the sand slid down from the side of an undersea ridge.
The tops of the mounds have living Lophelia pertusa coral. They also have pieces of broken coral. The mounds are one of the largest known places where cold-water coral can live in the northern parts of the world. These mounds are special because Lophelia pertusa, a cold-water coral, seems to grow directly on sand. Before these mounds were studied in 2000, scientists thought that Lophelia coral needed a hard surface to attach to.
The deep-water coral systems on the mounds are very delicate. Unlike corals in shallow water, they cannot handle small disturbances like waves. The mounds are also home to many Syringammina fragilissima. This is a giant single-celled organism, a type of protozoan. It is found in many deep-water areas, but it lives in very large numbers on the mounds and their tails. Individual Syringammina can grow larger than 20 centimetres (7.9 in). They are often very fragile.
The corals themselves provide a home for many other sea creatures. These include sponges, worms, crustaceans, and molluscs. You can also find starfish, sea urchins, and crabs there. Different types of fish have been seen, such as blue ling, roundnose grenadier, and the orange roughy.
Protecting the Mounds
On October 23, 2001, UK Minister Margaret Beckett promised to protect the Darwin Mounds. She made this promise at WWF's Oceans Recovery Summit in Edinburgh. The summit launched the Edinburgh Declaration, which aimed to get politicians and sea-related businesses to help protect the oceans.
Before this, large fishing boats used a method called deep-water bottom trawling in the area. This involves dragging heavy nets, sometimes weighing as much as one tonne, across the sea floor. A researcher named Jason Hall-Spencer found pieces of coral that were at least 4,500 years old in these nets. The nets were used by trawlers fishing off the coast of Ireland and Scotland. Pieces of coral up to 1 square metre (11 sq ft) were found in the nets of French fishing boats. These boats had been scraping the seabed 1 kilometre (0.6 mi) down. It is known that a lot of coral was destroyed by these nets. Some areas of the mounds themselves were scraped and flattened. The mounds are very old, and this damage is permanent.
After the mounds were discovered, three detailed studies of the area were done. These happened in June 1998, August 1999, and twice in the summer of 2000. Scientists used special tools during these studies. These included side-scan sonar, still cameras, video cameras, and tools to collect sand samples. However, no one knows the full extent of the damage caused by the heavy fishing trawlers.
On March 22, 2004, EU Fisheries Ministers met in Brussels. They agreed to give permanent protection to the United Kingdom's unique cold-water coral reefs. They recognized the Darwin Mounds as a very important habitat. Since 2004, deep-water bottom trawling in the area has been made illegal.
See also
- In Spanish: Darwin Mounds para niños
