An NYT story credits a policy called catch shares.
Under this system each boat is given a long-term share (say, 5 percent) of the total annual quota, to give the fleet a strong vested interest in rebuilding fish stocks. As Lubchenco explains: “If you have 5 percent of the pie, you’d like to see the pie grow.”
And here is Alex Tabarrok on technology that could help.
One thing to keep in mind is that alarmist claims that “fishing stocks are collapsing because of tragedy of the commons” are very old, but that various agreements and enforcement regimes for the last half century have been adequate to prevent a long term crisis in either supply or prices, judging from market data. I question whether the need for further legal innovation is really all that pressing.