They are also called feather duster worms and Christmas tree worms. Their brown or grey tube is soft and they don’t have a flap. Fan worms are found growing on the sea floor at all depths. They can also live on anything people build in the sea. When they extend their tentacles from their tubes they look like large round feather dusters.
There are many different coloured tentacles for the many species of fan worms. The tentacles are used to filter food from the sea.
Fan worms don’t have eyes but they can detect fish. When a hungry fish comes too close to fan worms they can whip their tentacles back into the tube with lightening speed.
The fan worm in this photo is not native to Australia. It was accidentally introduced in the ballast water stored in ships that move cargo around the world.