Supported by Nature
Nature-based solutions for a sustainable Baltic Sea
Learning sites for nature-based solutions
At Klintholm Harbour and off the coast of Møn, efforts are actively underway to restore the marine environment using two different nature-based solutions, collectively contributing to strengthening biodiversity and restoring important habitats beneath the water’s surface.
In Klintholm Harbour, ‘biohuts’ – also known as fish nurseries – have been installed beneath the docks, and off the south-western coast of Møn, a stone reef named Mads Rev has been re-established.
Both fish nurseries and the stone reef contribute to strengthening a balanced ecosystem – from harbour to the open sea. By recreating physical structures, an environment is created in which fish, mussels, algae and other marine species can thrive.
Both sites form the basis for ongoing observation, monitoring and knowledge-building. Klintholm Harbour forms the setting for the presentation of these learning sites. Here, visitors can explore the fish nurseries and view information boards about both the fish nurseries and the stone reef.
Educational visits
We offer educational visits for public authorities, associations, educational institutions and others with an interest in marine nature restoration. A visit provides access to the learning sites, an insight into work on nature-based solutions in coastal areas, and experience of a multi-stakeholder approach, in which collaboration between local and national stakeholders is central.
Please contact project manager Søren Sørensen for further information
In Klintholm Harbour
Fish nurseries
As part of the ‘Supported by Nature’ initiative, fish nurseries (Biohuts) have been installed in Klintholm Harbour on the eastern part of Møn. A fish nursery is a submerged nursery for fish, where small fish can hide and grow up in a protected environment. Each Biohut consists of a steel cage with a core of oyster shells, suspended beneath the bridges in the harbour. They mimic natural habitats and serve as shelters and feeding grounds, creating favourable conditions for a wide range of marine species.
The fish nurseries are not just a nature restoration initiative – they are also intended to serve as learning facilities where visitors and school groups can gain an insight into life below the surfaces and into how nature-based solutions can improve the marine environment. Efforts are being made to develop Klintholm Harbour as an educational hub and a local ‘hotspot’ for knowledge and inspiration about marine ecosystems.
The first fish nurseries in Klintholm Harbour were inaugurated in August 2024, and collaboration on the fish nurseries continues to develop.
In the coastal waters south of Møn
The stone reef 'Mads Rev'
In 2025, a stone reef named Mads Rev was re-established in the coastal waters south of Fanefjord Skov on Møn as part of the Supported by Nature project.
Stone reefs are among the sea’s most important habitats, where seaweed, mussels, fish, crustaceans and many other marine species find food, shelter and favourable conditions for growth. Over the past 100 years, a large proportion of the natural stone reefs in Danish waters have been removed, which has significantly reduced the habitats available to marine life. Mads Rev is a nature restoration initiative designed to help restore these valuable habitats and strengthen marine biodiversity.
Mads Rev has been re-established through close collaboration between Aarhus University, Vordingborg Municipality, local volunteers from the Møn Sports Diving Club, the Danish Society for Nature Conservation in Vordingborg and the Møn Stone Reef Association. Based on seabed surveys and underwater documentation, Aarhus University has developed a digital analysis tool which has identified the most suitable location for the stone reef.
The stone reef is not just a nature restoration initiative – it also serves as a learning site that provides insight into marine biodiversity and the methods used to improve the marine environment. At the same time, it can inspire future nature restoration initiatives in Danish coastal waters and demonstrate how authorities, researchers and local stakeholders can work together to bring more life to the sea.
About the project Supported by Nature
Supported by Nature is an international EU Interreg project aimed at promoting the use of nature-based solutions in the Baltic Sea region. The project runs from 2023 to 2026 and is a collaboration between UNESCO biosphere reserves from six countries around the Baltic Sea.
The project’s overall aim is to increase understanding of nature-based solutions and their contribution to improving environmental conditions in the Baltic Sea. This involves two key methods: learning by doing, where nature-based learning sites are established through collaborative approaches; and learning by experience, where understanding of nature-based solutions is enhanced through practical activities at the learning sites.
The long-term aim is that this increased knowledge will lead to more frequent and more effective use of nature-based solutions in planning processes and in the management of both land and marine areas.
As part of the project, a total of 17 learning sites are being established across the six countries around the Baltic Sea, where nature-based solutions are being demonstrated and further developed in practice. The focus is particularly on multifunctional wetlands, the restoration of watercourses and coastal marine habitats – measures that both benefit biodiversity and strengthen the resilience of landscapes to climate change.
The development of the learning sites is taking place in close collaboration with local stakeholders, who are actively involved in both planning and implementation. The learning sites will provide a framework for activities and outreach designed to strengthen local understanding of how nature itself can be part of the solution to environmental and climate challenges.
