The Seychelles, a small island nation in the Indian Ocean, did something pretty big.

Last month, the country of 115 islands agreed to protect 30 percent of their ocean territory, and in return a foreign investor group, the Paris Club, will cancel $30 million of Seychelles’ debt.

It’s quite a deal, and it comes with big potential perks for the planet. Marine reserves are one of the major ways we’ve seen countries take action to protect their natural resources in recent years. The 154,000 square miles of ocean named in the Seychelles deal will be protected, with a large area designated as a no-fishing zone, which means fish will get bigger and more abundant, while sensitive habitats like coral reefs will be protected from some damaging fishing practices. It will be the second-largest marine reserve in the Indian Ocean.