Or eat line&pole caught fish. It's much more expensive, especially the canned tuna, but I feel like if I can afford the more sustainable option then it's my responsibility
Searching for "pole and line caught tuna" will turn up a bunch. If you are in the US, Wild Planet probably has the best grocery store distribution. Raincoast seems bigger in Canada, but has some US distribution. American Tuna sells on Amazon and is great.
One of the other differences that most of the line caught tuna brands cook the raw tuna directly in the can, rather than cooking first and then canning. This results in much better texture. Other than price, it's a superior product in almost every way.