I was expecting him to exit with the crab attached to a finger, or even his nose.
Funny you should say that ..
I spent several months in Darwin doing restoration work after Cyclone Tracey & a mate with a light aircraft used to take us over to Grouse Is. (not Groot Is.) to visit a guy from Redcliffe who was employed to clear the dirt airstrip of buffaloes etc. in case it was needed for an emergency landing.
He told us, as we gorged ourselves on mud crabs & roll mops washed down with copious quantities of beer, that another of his duties was to provide first aid to the local ladies who use that same technique to harvest mudcrabs. He found that the best approach was Fria's Balsam applied liberally to the injured digit.
I favour the 'long bit of fencing wire' technique.