For the last couple of years, scientists and divers in South Florida have been watching as a new disease has been spreading along Florida reefs. It's a water-borne pathogen that kills stony corals — the big ones that serve as the foundation for reefs.
Scientists don't know what caused the outbreak. They do know that the number of different kinds of corals it attacks — and the rate they’re dying from it — is unprecedented. But so is the response.