Coral reefs, as vital to tropical fish as trees are to birds, are becoming more vulnerable to a process called "bleaching," which occurs when a spike in water temperatures causes coral to expel the algae that provide their kaleidoscope colors, leaving them prone to starvation or disease. Today, swaths of the once-psychedelic Great Barrier Reef in Australia have turned boneyard white and largely devoid of life.

Scientists fear a similar fate could await the Coral Triangle, a huge underwater wonderland east of Borneo endowed with a trove of biodiversity comparable to the rainforests of the Amazon Basin. Millions of people depend on its bounty to survive, a large share of them Malaysians, who eat an average of 125 pounds of fish each a year — more than double the world average.