Don't know about restrictions but they are good bait. We caught one for bait at Woodmans Point and the tarwhine were loving it. Would be good to know the legalities of it though...

If we can hit that bullseye, the rest of the dominoes will fall like a house of cards. Checkmate.

They would have to be a good bait of any of the rock walls in Perth. I used to use them off similar rock walls in a place called Yamba in NSW and the bream were all over them.

got a pic of the crab spear?

Yeah would like to see it

We just used to sneak up on them in stealth mode with an old knife commando style.

If we can hit that bullseye, the rest of the dominoes will fall like a house of cards. Checkmate.

However, they are easy to make. Grab a wire coat hanger. Untwist it so that you have a straight piece of wire. Grab some pliars, bend about two to three centimetres of one end to make a bit of a hook. Then use a file to sharpen the point of the hook.
When you stab the point into the crab the hook goes in through the shell and it can't get off.
You can either make a handle on the other end with the wire by forming a loop or if you want to get real fancy, you can cut the wire down, burn a hole in a thick piece of dowel and stick the end of the wire into.
The idea is to put some bait on a rock where you can reach the crabs with your spear and then stab them when they grab onto the bair, but the easiest way is to stab them when they are hiding in crevices.
Just need to see if is ok to use them.

What about a crab net with the fine diameter netting, with a nice bit of bait in the middle.

i was just down on the south wall, to windy for much fishing, but saw HEAPS of crabs, and two young cats!  once my wife saw the cats she was done fishing....she kept feeding little pieces of prawn to the cats but they wouldn't come too close.

I reckon those crabs would be awesome bait....let me know how you go with that spear, might just have to rig one myself!