Off the coast of northeastern Queensland, Australia, near Magnetic Island in Florence Bay, the Great Barrier Reef corals are having a baby boom.

“Every year there are more and more coral babies,” says Hillary Smith, a National Geographic explorer and ecologist at James Cook University in Australia.

That’s thanks to a simple but effective strategy for cleaning the region’s coral reefs: “seaweeding.” Like weeding a garden, seaweeding involves plucking big handfuls of large algae—sargassum seaweed in this case—off reefs and hauling them away.

When weeds grow in garden soil, they can take more than their fair share of water and sunlight stunting the growth of flowers. Coral reefs, worn down by human activities such as pollution and hot ocean temperatures, can similarly be