Meet the oceans’ unsung hero - the humble sea cucumber. An animal in the same family as starfish that looks like a lumpy sausage and lives on the ocean floor could help with some of the impact of global warming, pollution from fish farms and damage from the fishing industry that are threatening some of the oceans most important ecosystems. We meet the Australian researchers using drones to count the cucumbers to understand how their poo is helping coral reefs. And in Madagascar, we speak to the local communities which are learning to sustainably farm the creature, protecting the seas and increasing their income along the way. Repeat - originally broadcast in February 2023. Presenter: Myra Anubi Producer/Reporter: Lizzy McNeill Series producer: Tom Colls Sound mix: Annie Gardiner Editor: Penny Murphy Email: peoplefixingtheworld@bbc.co.uk (Image: Sea cucumbers. Credit: Getty Images)