Not so long ago, we thought the ocean was an inexhaustible resource. There would always be plenty more fish in the sea.

We now know this isn’t true. A growing proportion of the world’s oceans are overfished. And even though we’re fishing more intensively and using more advanced gear than ever, the total number of fish caught has plateaued. There simply aren’t as many left to catch.

On top of this, climate change and other human-driven pressures are placing even more stress on marine species.

Globally, governments are working to prevent further damage to ocean systems by establishing marine protected areas. However, our new research suggests these aren’t as effective as they seem.

Governments and communities are increasingly aware of the various threats our oceans face including fishing, marine heatwaves and overabundant species.

These compounding threats have prompted countries around the world to rapidly expand the coverage of marine protected areas – places where fishing and other destructive activities are restricted – over the past three decades.........

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