Rising temperatures transform Wadden Sea at record speed – researchers

The Wadden Sea, the world’s largest unbroken system of intertidal sand and mud flats in the southern North Sea, is changing at an unprecedented rate due to climate change, according to a report by Germany’s Alfred Wegener Institute for polar and marine research. “Rising temperatures and sea levels are changing the coastal morphology and sediment dynamics that have shaped the Wadden Sea for more than 8,000 years,” said the Institute’s Christian Buschbaum, adding that the North Sea has warmed nearly twice as fast over the past 60 years as global oceans. Heatwaves with temperatures three to five degrees above average will become more frequent and last longer, affecting the size of ecologically important habitats, like seagrass meadows and mussel beds, the researchers warned. They also reported a significant increase in invasive, warmth-loving species that are “completely changing the habitat”. “Massive reefs of Pacific oysters and hectare-wide underwater forests of algae from the Far East can easily be spotted by anyone who visits the region,” said co-author Buschbaum.

The Wadden Sea is a UNESCO World Heritage site stretching along the coast from the Netherlands to Denmark. It is of great ecological importance for many fish and bird species, such as the herring, oystercatcher and knot, which use it for at least one phase of their lifecycle. The area serves as a nursery and feeding ground, while also offering young fish protection from predators. Climate change has already affected migration patterns as some fish are migrating farther poleward, while other species are withdrawing to deeper, colder waters, the Institute said. Those species unable to shift their distribution range are forced to adapt to the rapidly warming conditions in the Wadden Sea. Adaptation responses include genetic changes, according to the report. The researchers said conservation measures and tourism concepts must be adapted to the changing environment.

Hundreds of climate activists last weekend protested on the German island of Borkum against government plans to drill for natural gas in the Wadden Sea. They warn that the plans for a platform put local ecosystems at risk and threaten the credibility of the country’s climate policies. Following an urgent appeal filed by environmentalists, a German court last week temporarily banned the construction of an electricity connection needed to power the planned drilling platform on the border between Germany and the Netherlands.