One would think that a volcano was not the most hospitable place for living organisms. However, the Borealis Mud Volcano, at 400 m water depth, acts as a sanctuary for a number of marine species. The underwater volcano Borealis Mud Volcano is located in the Barents Sea and was first discovered by researchers at UiT The Arctic University of Norway in 2023. The discovery received a lot of attention, and images of the volcano circulated around the world. Now researchers from UiT, in collaboration with REV Ocean, have finally published the results from an interdisciplinary investigation showing that Borealis mud volcano has a unique ecological role as a natural sanctuary for several marine species in the Barents Sea.

While some parts of the crater floor of Borealis appear inhospitable to a variety of organisms, the carbonate crusts -- a type of mineral formed thousands of years ago -- that characterized Borealis provide a suitably hard substrate for species of anemones, serpulids, demosponges, and sparse octocoral colonies. In addition, the carbonates offer both shelter and feeding opportunities, playing an important role in sustaining the local fish populations. The researchers observed large schools of commercially valuable species like saithe and various demersal species such as spotted wolffish, cod, four-bearded rockling, and redfish (Sebastes spp.) clustering around the jagged carbonate formations.

The researchers also found sediments containing extinct, microscopic marine organisms from up to 2.5 million years ago and that small "mud cones" in the volcanic system are emitting vigorous methane-rich liquids. The fact that the seabed around the volcano is also characterized by extensive carbonate deposits indicates that methane has leaked out, probably for thousands of years. She reminds that, in the longer term, Norway has committed to the 30x30 target (protecting 30 % of land and sea by 2030) for spatial conservation measures of representative marine ecosystems, including in the deep sea. Protecting large areas of the deep-sea floor along the Norwegian margin may result in seep refugia acting as source populations for wider recolonization and restoration of benthic biological communities.