That’s one of the dangerous things about coming to Australian beaches. Don't fear sharks or crocodiles trust me they stay away from people (most times

) Its the jellyfish and the very small blue-ringed octopus that make swimming in the sea water dangerous. The Blue ringed-octopus when it bites you with its beak-like mouth injects a numbing poison so it doesn’t feel like you’ve been bitten at all and until it bites you wont know its a blue-ring because they only turn white and blue when the are in defence mode and you very unlikely to feel the bite also you will only have a very limited amount of time to reach of hospital most people don't notice they have been bitten until its too late. Another thing that makes the ocean very dangerous.
