I'm not sure the difference in biology between tuna and YT. But check this article out. All 57 tuna caught and released survived. And if anything I feel that YT would be more hardy as they can withstand greater fluctuations in water temp. So maybe they'd be able to pull oxygen better from the water once they're 'catching their breath' after a fight? Idk
http://www.outdoorlife.com/blogs/gon...e-tuna-fishing
Nice release though!