Seaweed is being touted a solution to all sorts of environmental challenges, from feeding people and livestock, and reducing the need to cut down forests, to creating new materials to replace plastics. But how much of the oceans should be farmed, and what would that mean for the plants and animals that already live there? We speak to Scott Spillias from the University of Queensland about his new research. 

Plus, we catch up with Lauren Sandeman from Sea Shepherd about the campaign to end the use of shark nets in New South Wales. 

Image: A dolphin found recently drowned in a shark net in New South Wales. Mother Ocean Freediving.