We've used those opera nets for years with great success to catch crabs. They're really hard wearing. I've had one of mine for 9 years! I'd highly recommend them if you don't have one. Can use them off a wharf or in the surf. What did he use to keep it in place Mark? Just a rod holder? I've seen other ones that some local Asian people used off the wharves that had a flat round base and the top lifted up raising the sides about 200mm to stop the crabs escaping as they were pulled in. Both styles seemed to work really well.