Divers turn conservationists as corals bleach worldwide 

This underwater photo taken on June 14, 2024 shows Black Turtle Dive conservation teacher Sandra Rubio (R) and her student Nannalin "Fleur" Pornprasertsom (L) surveying bleached corals around Koh Tao island in the southern Thai province of Surat Thani. This underwater photo taken on June 14, 2024 shows Black Turtle Dive conservation teacher Sandra Rubio (R) and her student Nannalin "Fleur" Pornprasertsom (L) conducting a coral survey around Koh Tao island in the southern Thai province of Surat Thani. This underwater photo taken on June 14, 2024 shows bleached corals around Koh Tao island in the southern Thai province of Surat Thani. This aerial photo taken on June 15, 2024 shows Mae Head pier on Koh Tao island in the southern Thai province of Surat Thani. This photo taken on June 14, 2024 shows Black Turtle Dive conservation teacher Sandra Rubio (L) teaching coral conservation to her students in the Black Turtle Dive classroom in Koh Tao island in the southern Thai province of Surat Thani. This underwater photo shows Gavin Miller, the scientific program director from marine research center Global Reef, cleaning an artificial structure for coral planting around Koh Tao island in the southern Thai province of Surat Thani, June 16, 2024. Black Turtle Dive conservation teacher Sandra Rubio holds a coral health chart used by citizen scientists to track the health of corals, in the Black Turtle Dive classroom in Koh Tao island in the southern Thai province of Surat Thani, June 14, 2024. This underwater photo taken on June 14, 2024 shows fish swimming over bleached corals around Koh Tao island in the southern Thai province of Surat Thani. This underwater photo taken on June 15, 2024 shows a crown of thorns feeding amongst bleached corals around Koh Tao island in the southern Thai province of Surat Thani.

A diver glides over an expanse of bone-white coral branches, recording the fish that dart between the ghostly arms extending from the sea floor off the Thai island of Koh Tao.