Cone shells
If you collect shells . You'll really appreciate these attractive colorful cone shells but be careful! They are really snail-like and painful sting. If one of these innocent-looking creatures stings you, you must get to the nearest hospital as soon as possible
Sharks
Many different sharks live on the great barrier reef , but few are dangerous to humans shark attacks occur rarely. Still some attacks are fatal so you should always swim, dive or surf with other people and you mustn't swim at dusk or dawn, which is shark feeding time