Wal-mart and several other big seafood retailers have announced plans to buy only sustainably-caught fish. Judgements about sustainability will come from the Marine Stewardship Council, the Monterey Bay Aquarium, and others.
This incentive-based approach to conservation has the potential to complement laws and regulations in reducing or eliminating fishing practices that are harmful to fish or ocean ecosystems. Where requirements have been ineffective, perhaps better markets for sustainably caught fish will spur improvement.
This is good for fish and good for oceans.