Islands are the location of two extremes: they hold the greatest concentration on earth of both biodiversity and species extinctions.  The challenge to save them and their inhabitants from the triple threat threat of invasive species, sea level rises and global heating  seems immense, But the results when rescue teams are sent in are remarkably quick - a gecko thought be extinct reappears. Giant tortoises thriving in the wild once again. Now the not-for-profit organisation Island Conservation is running a challenge to begin restoring at least 40 globally significant island-ocean ecosystems by 2030.

Guest: Cameron Diver, Vice-President, Island Conservation.