I watched a documentry last night on Dish network sat. tv chanel 196 Current tv It was titled- slaughter the history of shushi. It told of
the downfall of the tuna stock and showed the auctions in Japan. It showed the japs trying to hatch and raise Bluefin. If you can find it and get a chance to see this it is awsom. This station also has had a program about tuna longlineing in Austraila alot like the program Sords on HIstory network
I have seen both shows. Although they already do it now I think you will see more tuna pen farming in the future as well as other species.