WASHINGTON — Just off the southeastern tip of the U.S., you’ll find an underwater masterpiece: North America’s only coral barrier reef. But, rising ocean temperatures are disrupting this once vibrant ecosystem.

The increasing ocean temperatures killed about 14% of the world’s coral reefs in just under a decade, according to a new study from the Global Coral Reef Monitoring Network. 

In the U.S., the majority of the loss is occurring along the coast of Florida, where just 2% of the original coral cover remains. 

“I think we are all pretty well acclimated to knowing that we are going to see more loss in the future,” said Jennifer Koss, director of the National Oceanic and Atmospheric Administration’s (NOAA) Coral Reef Conservation Program.

Water temperatures have risen 1.4 degrees Fahrenheit since 1970.  Koss said even a slight uptick in water temperature is dangerous, causing corals to become stressed and expel algae living inside them — a process known as bleaching. 

“The corals don't necessarily die at that point, but the longer they live without that algae, the more likely they are to die," Koss said in an interview with Spectrum News. "If water temperatures come back down, then the corals can re-recruit the algae, they can withstand a bleaching event. When the temperatures persist for too long, we do see mass mortalities."

But, bleaching is only one factor leading to coral loss in this area. A mysterious disease outbreak, first seen in 2014, has proven to be even more fatal. 

“We’ve never seen a disease like this before. For one to move as quickly with such mortality,” Koss said.

The disease, known as stony coral tissue loss, can infect and kill entire heads of coral in a matter of days. The infection causes the tissue of the coral to degrade and fall off, turning reefs white as they die. 

“We often talk about death by a thousand cuts," said Karen Neely, a coral ecologist at Nova Southeastern University. "That includes climate change, changes in water quality, even small things like anchoring on a reef. Stony coral tissue loss disease is the latest and biggest cut, but it is not the only one.” 

The cause of the disease has yet to be determined, but Neely suspects it's bacterial and spreads through the water. But, warming seas, pollution, development and climate change may have also been contributing factors. 

“It’s very difficult with coral diseases to even identify what is causing it,” Neely said. 

Spectrum News saw first-hand how the disease is progressing out on the water with researchers two years ago. Since then, the disease has progressed to all the reef sites in the Florida keys, including to the Dry Tortugas National Park.

“The Tortugas were clear of the disease until early June of this year,” Neely said.

Neely and a small group of scientists have been deploying among one of the more unusual medical interventions in recent history. Over the past two years, the team has been applying antibiotic goop to thousands of coral colonies infected with the disease. 

“We have high effectiveness there, an excess of 90-95%," Neely said. "There are examples when colonies will become re-infected and so we go back to a lot of these colonies and do doctors check ups on them and see if they have new disease legions — we deal with those accordingly."

Throughout 2020, Neely and her crew continued their work treating the coral. But, she says the pandemic above the surface halted a lot of their research.

“One reason is a lot of the labs that run samples like that got redirected for COVID samples,” she said. 

For the coral in Florida waters, there’s virtually no escape from climate change.

“For anyone who dives and sees our reefs, no one ever comes back and says that looks better than it used to, it always looks worse than it used to,” Neely said.

Still, amid a sea of bad news, there’s a glimmer of optimism. 

“Through research and sound management actions, we are seeing little rays of hope,” Koss said. “We are really hoping we can keep enough species and diversity among species alive, that through more care, corals will persist into the future."