What do you have in mind for the big 70th fish dan?!
If your fishing ANY method, have you tried putting down a bait trap for some of mini species? We had a butterfish in one recently? Also 15 spined and 3 spined sticklebacks can be caught easy enough with a fine mesh net from rock pools (if you can find them that is!) Failing that there are loads of similar looking species that may have been caught already and mis id'd. Also Portaferry shore road and the rocks along the way are full of worm pipefish, snake pipefish and possibly greater pipefish at really low water?
Tight lines... or nets... or traps!