Beavers once shaped Britain’s waterways, creating thriving wetlands and complex river systems brimming with invertebrates, amphibians, birds and fish before they were hunted to extinction 400 years ago. Beavers are a keystone species, referred to as ‘ecosystems engineers’. As we look to tackle the climate and biodiversity emergencies, restoring beavers to their former range across Britain will help us build climate resilient landscapes and restore freshwater habitats and the species that rely on them.