A fishery is sustainable when the amount harvested does not compromise future harvests. According to the U.N., 69% of fisheries are sustainable, while 31% are overfished or ‘over-exploited.’ Larger fisheries are typically managed better, so roughly 82% of consumed seafood is sustainable.
How should conservationists and NGOs approach MPAs? Closing an area of the ocean to fishing will increase the amount of fish in that area, but it does not protect the ocean from its greatest threats: carbon dioxide emissions and pollution. MPAs are also rife with social justice implications.
The mean trophic level of the world’s catch is not declining and the underlying theory that we begin fisheries by catching large valuable fish is incorrect. Lower trophic-level species like abalone and oysters are more likely to collapse from fishing pressure.