The only real solution is private property.
I agree. Not because I've looked at the specific fishing industry rather, because I've seen private property rights as the solution to most everything that has market value. A principle (or natural law) that is universal in its application.
Now that I think about it, I wrote above without even thinking about it but I naturally referred to fishing as an industry. Which it is -- from recreational to fleets of boats and stocking and all that it encompasses. A common denominator in all market and industries is that government should not interfere.