Sweden's only remaining cold-water coral reef, the Scken reef in the Koster Fjord, is under threat of extinction. Because of that, researchers from the University of Gothenburg have started a restoration project where healthy corals from nearby reefs in Norway are being removed and placed on the Scken reef.
Coral reefs are known for their rich biological diversity. In Sweden, only one reef-building coral species exists, a cold-water coral called Lophelia pertusa. Lophelia pertusa requires an environment with a constant high level of salinity and low water temperatures all year round. In Sweden, these conditions only exist in the northern part of Bohusln, where deep water from the Atlantic is led in via the Norwegian Trench.
"We've known since the mid-1920s that cold-water coral reefs exist here in Sweden," says marine biologist and researcher Mikael Dahl. "At that time, corals could be found in three locations in the Koster Fjord. Today, only the Scken reef remains, and it's in poor condition."
Some of the causes to this are the impact of trawling and increased sedimentation from eutrophication. Continuous observations with remotely operated vehicles (ROV:s) shows that the health of the reef slowly continues to decline.
"The red list assessment is currently in the 'under immediate threat' category. The Scken reef has been protected against trawling for more than a decade, but trawling damage have been observed on the reef several times after the legislation was set in place", says Mikael Dahl.
Three years ago, the protection of the reef was further strengthened when Sweden's first national marine park, the Kosterhavet National Park, was created. However, the Scken reef remains in poor condition.
Coral reefs are entirely dependent on larvae from other reefs in order to recover naturally after they have been damaged, and the researchers have for a long period of time set their hopes to larvae from the nearby
|Contact: Mikael Dahl|
University of Gothenburg