We had discussion with Mogi-san on the mortality of GT after being CnR , it's a concensus in Japan that in order to ensure the survivability of the fish , it's best not to remove the fish from the water or if the fish are to be weighed / measured , put them in an onboard livebait tank large enough to accomodate the fish to revive the measured / weighed fish before releasing it back . I believe Capt. Fukui Kenzaburo's Big Dipper has this tank and he has already recovered a few tagged fish since this practice was implemented a couple of years ago .
Jon .