Scientists collect healthy corals for gene bank as mysterious disease decimates reefs

A rescue mission to save Florida corals from a mysterious disease that’s devastating local reefs arrived in Miami on Friday with 400 specimens that may be used as a gene bank to potentially breed new colonies and repopulate reefs in the future.

Marine research vessel Makai returned from a five-day cruise at Dry Tortugas National Park with tanks full of corals that haven’t yet been infected by the disease, known as stony coral tissue loss disease. The corals will stay at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science for a few weeks before they are shipped to zoos and aquariums nationwide.

Coral reefs worldwide have been threatened by pollution, development and by more frequent bleaching events, which are associated with climate change. In Florida, warmer temperatures cause nutrient-rich waters to produce more seaweed, which can suffocate corals. Dredging has also affected colonies, and increased boat and ship traffic around the Florida Reef Tract has also taken a toll on corals.

The fast-spreading disease is a new and alarming factor hammering the fragile ecosystem that’s vital for marine life and storm surge protection.

“They are the rain forest of the sea,’’ said Andrew Baker, a marine biologist at UM’s Rosenstiel School and coral scientist participating in the multi-agency rescue program. “Coral reefs are the more ecologically diverse ecosystems on the planet and if we lose them, we lose millions of species that depend on them.’’

Marine biologists place corals in a holding tank where they will stay for a few weeks before being transferred to facilities all over the country as part of a coral rescue program Adriana Brasileiro

The effort to protect Florida’s reefs has taken on added urgency because corals serve as a buffer that protects coastal areas against hurricanes and storm surge, Baker said. By collecting healthy corals and using them as a living seed bank for future breeding, scientists hope to preserve their genetic diversity until a cure for the disease is found.

UM’s Rosenstiel School is one of seven research facilities that are acting as temporary hosts for specimens collected for the Florida Coral Rescue Project, part of an ambitious program led by the National Oceanographic and Atmospheric Administration. Scientists are targeting 23 species of corals that are considered priorities for being more susceptible to the disease or those that have higher coral-building capacity.

At UM’s coral nursery, each coral that arrived from the rescue mission was dipped in a solution of antibiotics to disinfect for bacteria and parasites that may have accumulated during transport aboard the Makai. After soaking for about 15 minutes, they were gently placed into holding tanks. Scientists from the Florida Fish and Wildlife Conservation Commission, National Park Service, Nature Conservancy and Florida Department of Environmental Protection also participated in the mission.

Scientists are trying to determine what causes the disease and are working to find a cure before the entire reef is wiped out. The coral disease was first observed in 2014, and it stunned scientists for the speed with which it infected the reef. It has also been killing corals all year round, unlike other coral diseases. Most events that regularly kill corals in Florida are associated with warmer sea water temperatures, which occur during the summer months. When the temperature drops, the disease pathogens usually die and cease to attack corals.

Another unprecedented trait of this devastating outbreak is that it has affected 23 species, or nearly half of Florida’s coral species.

“It’s probably the worst episode of coral disease on record, anywhere in the world, because of how widespread it is and because it affects multiple species,’’ Baker said.