Reefs are often covered with algae and sponges, and have overhangs and crevices that provide shelter. Animals use these spaces by hiding among the weed, squeezing into the gaps between rocks and in kelp holdfasts to avoid being swept away by waves or strong currents. Some are cryptically coloured to avoid being eaten by the fishes that also congregate around reefs, while others are brightly coloured.

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Reefs habitat video

Near the mouth of the bay you get a lot more rocky reefs. These reefs are actually old sand dunes that over thousands of years have turned into rock. Now these reefs are covered with a thick carpet of kelps and seaweeds. These areas have one of the highest diversities of seaweeds of anywhere in the world. These seaweeds in turn form the food for abalone, sea urchins and all sorts of fishes.