Salmon are returning to Europe’s Rhine River, but they still have one key barrier

The Rhine used to be home to a huge population of Atlantic salmon, which made their way all the way up to Switzerland to lay their eggs. Since the 1950s, construction of hydropower facilities has stopped the salmon migration, and now the species is all but eliminated from the Rhine. A decades-long plan to restore the salmon and their migration route along the Rhine is almost complete. But as Emily Haavik reports from Basel, Switzerland, there’s one key juncture at a dam in France, where the salmon’s passage has not been figured out yet.