Pokey, I have one "phobia" in life and it is sharks.... Crocs etc are fine with me, they don't give me the chills or an inexplicable fear, but sharks do. I am of the mind they are ALL just WAITING for ME to enter the water to strike...!!!!! Now that said, shark attacks are statistically very very low here, there are plenty of patrolled and netted beaches where you would be fine. That said... don't expect ME to accompany you into the water.... LOL But that is just me...!!! I think I saw Jaws when I was too young...!!
Funny, when I was last up in the NT you got both Crocs and Sharks in the rivers, you could have a great honking 4m Salty near the boat or bank where you were fishing and I was find....a 1m shark shoots by and I am trying to fly !!!