Off the coast of Cape Town, South Africa, two powerful ocean currents meet. The cold Benguela Current in the west mixes with the warm Agulhas Current at the tip of the continent, resulting in an area rich with marine biodiversity.

The rugged coastline also produces powerful swells at a place where the reefs come out of deep water, making it the perfect playground for fur seals—social, playful creatures that surf the waves like dolphins, just for fun.

Photographer Thomas Peschak had been watching these seals for years and wanted to take a photograph of them surfing from a unique underwater perspective—but first he had to figure out how to do it without getting himself seriously injured or killed.

“When waves were really big