Researchers work to protect coral, as signs of a deadly disease appear off the Texas Gulf Coast

From Houston Public Media: 

At the Moody Gardens aquarium in Galveston, around 100 different corals sit in water tanks in an enclosed room. Some are brown with markings that make them look like brains. Others have bright green coloring in between their grooves. All were rescued from Florida after a deadly coral disease, known as stony coral tissue loss disease, started infecting reefs there.

“There’s not exactly a book about how to take care of a coral, and a lot of these species have never been taken care of in captivity prior to this program,” said Brooke Carlson, a senior biologist at Moody Gardens.

Moody Gardens is one of around 20 zoos and aquariums across the country that took in rescue corals from Florida back in 2019, with the goal of raising them in captivity and eventually breeding them to restore damaged reefs.

“The plan was to take as many healthy corals out of the population as possible and put them in captivity so that they were safe from the disease,” said Carlson.

First detected in Florida in 2014, stony coral tissue loss disease is characterized by how quickly it spreads and its high mortality rate. Once infected, corals typically die within weeks to months. Wildlife officials are racing to protect the corals and prevent the disease from spreading further.

Since it was first discovered in Florida, stony coral tissue loss disease has spread to more than 20 Caribbean countries and territories. Now, divers have noticed potential signs of the disease at the Flower Garden Banks National Marine Sanctuary, a protected area some 100 miles off the coast of Galveston.

“They were seeing lesions on some of the corals. It’s like a white line where tissue has been lost,” said Michelle Johnston, a research ecologist with Flower Garden Banks.

Johnston said they had prepared a response plan after seeing what happened in Florida.

“Within three days of those observations, we were out responding,” she said. “We didn’t waste any time.”

The response plan included taking samples of both healthy and sick corals for analysis and applying an antibiotic treatment – a mixture of amoxicillin and putty – to the lesions on some of the infected corals.

Johnston said the disease doesn’t appear to be progressing as quickly as it did in Florida, which could be because the coral at Flower Gardens is healthier and more resilient. Or, it could mean it’s a different, less lethal disease.

“Right now, only time will tell,” Johnston said.

The problem is that researchers still aren’t sure what exactly causes stony coral tissue loss disease – they don’t know whether it’s bacterial, viral, or a combination of the two.

“For coral disease research, we’re still kind of in the Dark Ages,” said Andy Bruckner, Research Coordinator at the Florida Keys National Marine Sanctuary. “We’re kind of like where we were with human medicine in the late 1800s. We’re just learning.”

Bruckner said globally, corals are already under a lot of stress from things like ocean warming and acidification due to climate change and poor water quality from pollution. This stress makes them more vulnerable to disease.

“One of the reasons why this disease has become so severe is the corals then are also concurrently sort of compromised by environmental stressors,” he said.

Bruckner is one of the authors of a five-year action plan recently launched by the National Oceanic and Atmospheric Administration (NOAA) to respond to stony coral tissue loss disease.

During a call announcing the plan, federal researchers said they view the disease as a potential global threat and want to prevent it from spreading to reefs in the Indo-Pacific. They’re hoping to hone in on what’s causing it, how it spreads, and how to diagnose it.

Bruckner said ideally they want to create a simple test, like the kind doctors use for strep throat, to quickly diagnose outbreaks.

“We’re looking to develop those same sorts of tools for corals, so that we can go in and when we see a disease outbreak, we can right away, say ‘Yes, this is stony coral tissue disease,’ or ‘No, it isn’t,'” he said.

Bruckner said being able to diagnose the disease will help them implement more successful treatment plans.

Continuing to protect and breed healthy corals in captivity is also part of the new action plan. Healthy coral from Flower Garden Banks National Marine Sanctuary has already been sent to Moody Gardens, where it’s under the care of Brooke Carlson.

“They’ve been doing really well for this month that we’ve had them,” Carlson said.

The corals from Flower Garden Banks are being kept completely separate from the Florida corals, since they’re from different ecosystems, but Carlson said a lot of what they’ve learned from caring for the Florida coral can be applied – like their food preferences.

On a recent Wednesday, Carlson and her team started prepping lunch for the Florida coral at the lab, combining ingredients like zooplankton and oyster tissue in a pitcher.

The biologists use a turkey baster to place the liquid meal on top of each individual coral.

“Beyond just their skeletons growing bigger, they are growing thicker tissue – so what I like to call fluffier corals,” Carlson said.

Soon, they’ll be ready to be sent off to another facility for breeding.

While coral may not have the initial charisma of other sea animals, Carlson said after spending so much time with them she’s come to learn all the subtle differences between each individual coral.

“Everyone can relate to a mammal, but it’s harder to kind of relate that same emotion towards a coral, when they kind of just look like a slimy rock,” she said. “But being able to see them respond to food, seeing them thrive in this environment has been extremely rewarding.”

Carlson said protecting coral is essential because they serve as the foundation of the ecosystem, providing a habitat and food for so many species.

“Without the corals, the ecosystem could crumble,” she said. “It’s very important for these corals to do well, and hopefully make their way back to the wild. That way, we can help rebuild this really crucial ecosystem.”

If you found the reporting above valuable, please consider making a donation here. Your gift helps pay for everything you find on texasstandard.org and Houston Public Media. Thanks for donating today.