Emergency Expedition Saves Thousands of Diseased Corals in Florida’s Dry Tortugas National Park

Emergency Expedition Saves Thousands of Diseased Corals in Florida’s Dry Tortugas National Park

The world’s coral reefs are in peril. Various factors – from climate change to pollution runoff to diseases – have led to a sharp decline in the number of healthy corals, both locally near Florida as well as across the globe. For many years, research scientists at Nova Southeastern University (NSU) have been studying corals to understand not only what is killing them, but what we can do to mitigate those impacts.

To that end, an emergency response mission to save corals in Dry Tortugas National Park was recently conducted and the results exceeded researchers’ expectations, with more than 6,000 disease-affected coral colonies being treated.

Stony coral tissue loss disease (SCTLD), a devastating marine pandemic that has spread throughout several areas of the wider Caribbean, was first documented in the Dry Tortugas region by National Park staff in late May. The disease has been spreading through Florida’s Coral Reef Tract from its origin near Miami since 2014. It affects at least 25 susceptible coral species, with mortality rates from 66% – 100%.

“Because the disease is still in the early stages within the Dry Tortugas, we knew quick action was needed,” said Karen Neely, Ph.D., a research scientist at NSU’s Halmos College of Arts and Sciences.

So, an intervention mission, funded by the National Oceanographic Atmospheric Administration’s (NOAA) Coral Reef Conservation Program and the National Fish and Wildlife Federation’s emergency coral fund, was launched. Led by Neely, scientists from NSU and Florida Atlantic University’s (FAU) Harbor Branch Oceanographic Institute teamed up to carry out the largest coral disease intervention effort to date.

Over the course of the 10-day mission, the team surveyed and treated disease-affected corals in an area the size of 146 football fields. Disease-affected corals were treated with a recently developed topical antibiotic paste that is known to halt the disease lesions and increase corals’ chances of survival.

“This is akin what humans put on a rash or other skin infection,” Neely said. “This approach has proved successful in other areas, so we knew this was the best chance we had at stopping the spread of the disease in the Dry Tortugas.”

Neely said this intervention method has been successfully used since 2019 at targeted sites throughout the Florida Reef Tract and in other parts of the Caribbean. Prior to this expedition, intervention efforts in Florida totaled just over 4,000 treated corals, with two-year survival rates of treated corals exceeding 96%.

The 6,038 corals treated on the Dry Tortugas mission represented 27 species, including several that are nearly extinct elsewhere in Florida. Some of these corals are the largest and oldest animals in the state, and they were treated in order to preserve one of Florida’s most spectacular coral reef ecosystems. Neely attributed the success of the mission to “a highly capable team of trained coral scientists and a focused mission of intervention. A great research platform and perfect weather conditions helped too.”

“The number of corals lost to this new disease is staggering and will restructure coral communities in South Florida for decades,” said Dr. Joshua Voss, a collaborator on the mission from FAU Harbor Branch. “This expedition demonstrates that targeted concerted intervention efforts, led by champions like Dr. Neely, can give us hope for conserving some of Florida’s most impressive coral reef habitats.”

Coral disease intervention efforts within Dry Tortugas National Park will be continued by NPS staff, and efforts throughout the rest of the Florida Keys will be continued by Neely and the research team.

This research was made possible with support from the National Oceanic and Atmospheric Administration’s Name of Program, grant #0302.21.073586