Do you like fish curry or grilled shrimp? If so, marine protected areas (MPAs) are good news for you. That’s because fish — and other marine animals and plants — that are threatened by thousands of tons of plastics, pesticides and toxins that pollute our oceans are being protected in MPAs. When fish ingest toxins released by plastic refuse, the toxins enter the food chain, endangering animals and humans alike. But MPAs give us a chance to keep sections of the ocean free of plastic debris, allowing ocean habitats and the species they support to recover and thrive.

Some MPAs allow regulated fishing or recreation, while others ban it completely. MPAs have been established along coastlines, around coral reefs, islands or mainland fisheries, and far from any land at all. All protect a broad range of marine life and habitats.
Scientists estimate that to safeguard our natural marine resources, 30 percent of the world’s oceans should be protected. Today about 3 percent is adequately protected. But by designating MPAs along their coastlines and in deep ocean areas, countries and international organizations can increase the percentage of protected ocean.

How do they work?
MPAs along coastlines help maintain mangrove and cypress swamps, coral reefs and other natural barriers. They protect the shore land from hurricanes, and shelter marine plants and animals.
MPAs also bring economic benefits. The fishing industry prospers when there are more fish to catch. Coastal marine sanctuaries attract tourists who help support local economies. Scientific monitoring and enforcement of MPA rules creates additional jobs.
Good news for lobster lovers
In the United States, California’s network of 124 MPAs shows what can be done. California, with a coastline of almost 1,800 kilometers, completed its coastal network of MPAs in 2012, creating more than 120 underwater refuges that extend from Oregon to Mexico.
“As safe havens, underwater parks offer a home and refuge for big, old, fat, female fish to recover, grow and replenish our oceans,” according to the nonprofit group California MPAs. Around California’s Channel Islands, where MPAs have been in place for 10 years, a 2012 study found that lobsters were more abundant and larger in protected areas, with an average of five more legal-sized lobsters caught per trap inside the MPAs than in nonprotected waters.

The most successful network of MPAs is around Australia’s Great Barrier Reef, says Woods Hole Oceanographic Institution scientist Simon Thorrold. “We’ve got some of the best evidence there in terms of protections,” he says. “It is a multiuse reserve: About 30 percent of the reefs are no-take reserves, and the rest have different levels of protection.”
Another possible MPA benefit occurs when adult fish migrate beyond MPAs and repopulate areas where their population has been depleted. Scientists call this “spillover.”
Spillover may be key to repopulating the rest of the oceans. “If at some point we get CO2 emissions under control and we start to reverse that, then we’ve got areas that can potentially seed other areas,” Thorrold says.

Upholding the rules
A sanctuary is only as good as its enforcement. Monitoring MPAs is a huge task. Drones and satellite technology can observe and document illegal fishing. Monitoring the health of marine ecosystems is a bigger challenge. For that, Thorrold says, “You’ve got to be on the water. You’ve got to be sampling in the water.”
Surveillance, interdiction and prosecution of offenders all are necessary and all are expensive. The island republic of Palau, with 80 percent (500,000 square kilometers) of its waters designated as protected areas, set up a crowdfunding campaign to help finance MPA enforcement.
The United States is now home to the world’s largest marine protected area, Papahanaumokuakea Marine National Monument, and it remains committed to ocean conservation.

What can you do?
- Use less plastic. Take reusable bags for shopping.
- If you eat seafood, make sure it is sustainably caught.
- Reduce your carbon footprint by driving less, taking public transport, walking or biking; cut back energy use at home; recycle.
- Find out about MPAs near you. Visit them and volunteer to keep them clean.
- Support organizations dedicated to saving the ocean, such as the World Wildlife Fund for Nature and the International Union for the Conservation of Nature.
- Encourage your local political leaders to support MPAs.