What object do dolphins use as tools in the wild?

What object do dolphins use as tools in the wild?
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Here this episode’s quiz: wild dolphins off the coast of Australia have been observed using a ‘tool’ to help them forage – what tool is this?  Think you know the answer? Surf on over to The Dolphin Communication Project website and click on Contact to leave us a message with your answer. Winners will randomly be chosen from the correct answers, and will be announced on out next show.