‘Small changes can make a big difference’: 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 habitats On 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 defend Falmouth harbour, they disappear in a swish of florescent pink and green fins.

They are volunteers, trained by the Cornwall Wildlife Trust to use underwater cameras and floating GPS devices to detect changes in marine habitats over time.

Two volunteers, Simon Tagney and Max Behnert, prepare to survey the seabed beneath the 16th-century St Mawes Castle.

Photograph: Luke Gartside/The Guardian Continue reading...