Record seawater temperatures in recent days have resulted in widespread coral bleaching in Florida's coral reef, the third largest in the world.

A tourist boat captain Brian Branigan said: "What’s happened in the last two weeks, just two weeks’ time, is nothing short of a cry for help. It’s terrible, shocking -- I want to cry myself when I’m in the water snorkeling -- to see this. And I contacted some friends of mine and said, 'You know, the reef has bleached.' It’s something that happened pretty much overnight."

Alex Neufeld from the Coral Restoration Foundation said: "What we’ve seen in South Florida in the last couple of weeks is a really intense heat wave that has brought a lot of really, really high ocean temperatures to the waters of the Florida Keys. And what that means for our coral reefs is that they’re under a lot of stress. And they are beginning to bleach and in some places die en masse."

He explained: "A coral is an animal that secretes a skeleton that fuses with the skeletons of its neighbors. And inside those coral animals live an algae. And the algae gives the coral its color, brown, green sometimes reds or purples. When the water gets too hot, that relationship between the coral animal and the algae breaks down, and the animal expels the algae into the water column. And then what you’re left with is the translucent, clear body of the coral animal against the backdrop of its white skeleton. And so coral bleaching refers to that process."

He continued: "Just in the last couple of weeks, we’ve been in our nurseries collecting representatives of every coral species and every genetic strain of coral that we work with, and pulling them into land-based facilities where the water parameters can be controlled and where they can be safeguarded. We’ve taken representatives from all of those corals and all of those strains. We’ve actually moved them to physically different locations to further safeguard and build in a bit of redundancy for those critical species and those critical aspects of genetic diversity."