‘It’s the unseen pollution’: how getting farmers, fishers and beavers together could save a Cornish river

A local initiative is testing simple ways to stop algal blooms in the River Fal threatening some of England’s most biodiverse marine habitatsOn a rocky beach in Cornwall, a group of wetsuit-clad freedivers and snorkellers are wading into the shallows. Below St Mawes Castle, built by Henry VIII to…