I sail Pinnaroo on a regular basis and the only time I think about sharks is when I'm actually in the water, as opposed to sailing across it.
Putting aside the occasional water start, when I have been known to cast my eyes downward in a pang of paranoia

, I like to think windsurfing is not a high shark-risk activity, unless your break some kit and have to paddle in.

I snapped a mast once wavesailing out the back of Little Island. Happened at 6pm. I made landfall at 9pm after a 3 hour paddle. I was fairly crapping my boardies on the way in, particularly when it got dark.
Coulda' handled whipping out a Shark Shield for the paddle in, with my legs dangling off the back of the board. How portable are they? Could you carry one in a backpack or would it be too much of a pain in the ass?