Well you've mentioned the location, what his ski looks like and your face is on ya profile, all on one of Australia's more popular fishing forums. I'd be a bit more covert about it if I were you.
Get a motion censored camera set up happening, then approach the police with irrefutable evidence. Either that or get another crabber with some attitude onto it, grab some popcorn and a beer and watch the fireworks. Letting his tyres down will always buy you some time and taking your crabs back would be a good plan too. Get all the local guys that crab to approach him as he comes into greet his flat tyres post theft. Nice and easy just a few logistics to sort.