The single greatest threat to the diversity of life in our oceans over the past 50 years, more than climate change or plastic pollution, has been unsustainable fishing practices.

In much of the ocean, there is little to no regulation or oversight of commercial fishing or other human activities. That’s part of the reason about a tenth of marine plant and animal species are considered threatened or at risk.

It’s also why countries around the world have been creating marine protected areas.

These protected areas, covering over 11.6 million square miles (30 million square kilometers) in 16,000 locations, offer refuge away from human activities for a wide variety of living creatures, from corals to sea turtles and whales. They give fish stocks a place to thrive, and those fish spread out into the surrounding waters, which helps fishing industries and local economies.

In the U.S., however, marine protection is being dismantled by President Donald Trump.

Trump issued a proclamation on April 17, 2025, titled “Unleashing American commercial fishing in the Pacific,” ordering the removal of key protections to allow commercial fishing in parts of a

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