In the 18th and 19th centuries, wild oysters were so abundant in European oceans that they were a dietary staple for rich and poor people alike. Overfishing and steam-powered dredges put an end to that era, but the importance of oysters wasn’t forgotten – not only as a protein-packed food source but also as an environmental asset. Oysters filter out nutrients and pollutants, build habitats for other aquatic species and, in large enough reefs, can act as natural breakwaters.
Today, efforts to restore native oyster habitat are underway across Europe. To support that work, a group of scientists attempted to map the historic extent of wild native oysters. Gathering more than 1,600 records published over 350 years that described the presence of oyster habitat in France, Denmark, Ireland, the UK and beyond, they found that prior to the 20th century, oyster reefs covered more than 1.7 million hectares across European oceans. They wrote about their research in a recent paper in Nature Sustainability. Lead study author Ruth Thurstan, a historical ecologist at the University of Exeter, spoke with MapLab editor Laura Bliss about the project.