July 24, 2025 — Marine protected areas cover more than 8% of the world’s oceans today, but they can get a bad rap as being protected on paper only.
While the name invokes safe havens for fish, whales and other sea life, these areas can be hard to monitor. High-profile violations, such as recent fishing fleet incursions near the Galapagos Islands and ships that “go dark” by turning off their tracking devices, have fueled concerns about just how much poaching is going undetected.
But some protected areas are successfully keeping illegal fishing out.
In a new global study using satellite technology that can track large ships even if they turn off their tracking systems, my colleagues and I found that marine protected areas where industrial fishing is fully banned are largely succeeding at preventing poaching.
What marine protected areas aim to save
Picture a sea turtle gliding by as striped butterfly fish weave through coral branches. Or the deep blue of the open ocean, where tuna flash like silver and seabirds wheel overhead.
These habitats, where fish and other marine life breed and feed, are the treasures that marine protected areas aim to protect.
A major threat to these ecosystems is industrial fishing.
These vessels can operate worldwide and stay at sea for years at a time with visits from refrigerated cargo ships that ferry their catch to port. China has an extensive global fleet of ships that operate as far away as the coast of South America and other regions.
The global industrial fishing fleet – nearly half a million vessels – hauls in about 100 million metric tons of seafood each year. That’s about a fivefold increase since 1950, though it has been close to flat for the past 30 years. Today, more than one-third of commercial fish species are overfished, exceeding what population growth can replenish.
When well designed and enforced, marine protected areas can help to restore fish populations and marine habitats. My previous work shows they can even benefit nearby fisheries because the fish spill over into surrounding areas.
That’s why expanding marine protected areas is a cornerstone of international conservation policy. Nearly every country has pledged to protect 30% of the ocean by 2030.
Read the full article at The Conservation