Wadden Sea Day 2025: Crossing the Dike
On 28 August, around 150 international representatives of science, nature conservation, politics, and the economic sector gathered for the Wadden Sea Day 2025, held under the theme “Crossing the Dike” at the UNESCO World Heritage Wadden Sea Visitor Centre in Wilhelmshaven. The event explored the diverse and interwoven relationships between the Wadden Sea and its hinterland.
The Wadden Sea is more than a shared marine ecosystem of Denmark, Germany, and the Netherlands. It is an open system, shaped both by natural processes and a long history of human influence. Life here is dynamic –water, sediments, nutrients and countless species interact and connect the open North Sea to the hinterland beyond the dikes. The coastal marshlands—once tidal flats—still retain traces of ancient tidal channels, demonstrating the rich geological and cultural landscape history. The influx of watercourses into the Wadden Sea and the dependencies of inland water management on hydrological conditions in the marine environment illustrate the close link between sea and land.
Eight expert presentations highlighted the range of ecological, landscape and cultural connections between sea and land. A notable contribution came from Katy Owen (Norfolk, England), who expanded the discussion to include the entire North Sea region.
Inspiration for a sustainable coastal landscape
Peter Südbeck, Head of the Lower Saxon Wadden Sea National Park Authority, emphasised: “The construction of dikes over the past centuries has reclaimed large areas of the Wadden Sea. To secure a liveable coastline that can adapt to climate change, we must rethink the role of the dike. This requires a shared vision for the cultural and natural landscape of the coast. The link between the UNESCO World Heritage Site and the Wadden Sea Biosphere Reserve provides important momentum for this work.”
Anne-Marie Vaegter Rasmussen, Chair of the Wadden Sea Board, added: “Coastal protection measures such as dike construction have reduced the interconnectivity between hinterland and Wadden Sea. As we come to understand that both nature and humankind can benefit from softening these artificial barriers in favour of natural dynamics, the Trilateral Wadden Sea Cooperation is investigating how to incorporate nature-based solutions in coastal protection measures.”
Cormac Walsh (Carl von Ossietzky University, Oldenburg) summarised his overview: “Effective conservation of the Wadden Sea requires an integrated approach that accounts for the interdependencies between the Wadden Sea, its coastal hinterland, and the broader North Sea. Nature conservation and the protection of natural heritage benefit from a greater consideration of cultural heritage and social values.”
Sascha Klöpper, Executive Secretary of the Common Wadden Sea Secretariat, reflected: “The Trilateral Wadden Sea Cooperation began with nature conservation. Today, socio-economic dimensions are equally important, particularly the cumulative effects of human activities. Dike construction is a prime example: it provides safety but also brings complex consequences for people and ecosystems. This makes it essential that we address these challenges together and across borders, as we do at this Wadden Sea Day.”
The Wadden Sea Day 2025 highlighted the value of a holistic view of the interactions between sea and land for the protection and sustainable development of the Wadden Sea. The various expert presentations underlined the need to rethink traditional coastal protection measures and shift focus to nature-based solutions.
Wadden Sea Day
The annual Wadden Sea Day has been jointly organised by the Common Wadden Sea Secretariat and the Lower Saxon Wadden Sea National Park Authority since 2006 and serves as an exchange forum among the international scientific Wadden Sea community.
Impressions
