Volunteers Rescue Florida's Reefs.

Volunteer diver Yasushi Kato scrubs algae from a line holding a piece of critically endangered staghorn coral at an underwater nursery maintained by the Coral Restoration Foundation (CRF). Vast thickets of staghorn and elkhorn corals used to be found along the Florida Reef Tract, but over the last 40 years, 97 percent of them have died. CRF, with the help of hundreds of volunteers a year, has grown and planted more than 100,000 corals in the past decade to try to restore these ecosystems.