Coral reefs cover less than one percent of Earth's surface, but as CBS News correspondent Daniel Sieberg reports, they're home to millions of marine plants and animals.
Rising ocean temperatures have claimed 20 percent of them around the world since the 1950s and another 50 percent could be wiped out by 2030.
Sieberg took a closer look at the corals of Biscayne Bay with one researcher who is embarking on an innovative but controversial experiment to protect the reefs. Andrew Baker hopes to, in a sense, "inoculate" the coral to build their resistance to the threat of rapidly warming waters.
"Basically, we're gonna go down and very carefully, almost surgically, remove these colonies," Baker said as they began their dive. "We're gonna pick about a dozen of these colonies."
About 10 miles off the coast of Miami, Sieberg watched as Baker and his team harvested a dozen Mustard Hill corals, the first step in his experiment. This reef system is today a fraction of what it was just 20 years ago.
"So, the corals that would normally be building this underwater structure, building this habitat, they've all been lost," said Baker.
Lost to what's called "bleaching." Corals thrive because of their give-and-take partnership with microscopic algae, each providing food and protection for the other.
"The problem is," Baker explained, "that partnership between the coral and its algae is very, very fragile, very sensitive. And all it takes is a degree or two above the normal temperatures and corals will lose these algae."
Once the vibrant coral has turned to a ghastly shade of white, only a lifeless landscape remains.
Reporter's Notebook: Sieberg shoots a behind-the-scenes look at this report.
Back in the lab, Baker proudly showed off one of the world's great collections of coral, about 12,000 samples collected from reefs all over the world.
Coral DNA is stored by the researchers in a super-cooled vault. What Baker's team discovered here is what gives him hope - that there are varieties of that life-giving algae. A few, from places like Africa, have a higher tolerance to heat.
Some researchers say Baker's plan to inject corals with the hardier algae is a crapshoot at best, but he says that's no reason not to try.
"We need to do everything we possibly can to save the remaining ones we've got and that includes doing everything we can," said Baker. "If my research might be able to help, then I'm willing to give it a go."