Secrets of Cuba’s reefs
FAU-led research yields good news for coral off Fla.
It was a rare peek at Cuba’s coral reefs in May, and what researchers found was good news for Florida.
The island nation’s 1,500 miles of coral reef — a stretch roughly equivalent to the driving distance from Miami to Boston — were awash in marine life. And that’s important to Florida because the two ecosystems are connected by a current that likely lets coral eggs drift to the Keys, and fish and lobster larvae might also be going along for the ride, scientists say.
“We are downstream, so what happens to their reefs will likely affect Florida’s reefs,” said John K. Reed, a Florida Atlantic University research professor.
He led a team of U.S. and Cuban scientists on an expedition around Cuba’s coastline, from May 15 through June 13. Cuban researchers didn’t have access to a remotely operated vehicle to study the deeper regions of the coral reef ringing the country, so their previous research had been limited to about 100 feet.
The team’s underwater rover, launched from the University of Miami’s F.G. Walton Smith research vessel, captured 100 hours of high-definition video and took over 20,000 pictures, many at depths of 500 feet.
Near a tiny islet off the north coast of Cuba, they found a reef with an abundance of marine life, including brightly colored sea fan corals and schools of small fish. The reef, which was protected by a maze of regulations, had been a mystery until the mission.
“It was a big unknown,” Reed said.
The researchers saw little evidence of coral disease or coral bleaching, which is related to water temperature. Bleaching weakens coral and makes it vulnerable to disease.
In 2014 and 2015, more than half of the coral in the Florida Keys National Marine Sanctuary experi-
enced bleaching. Some areas recovered, but last year researchers noticed a new type of coral disease in the region and up to West Palm Beach, Reed said.
“Not quite sure exactly what it is, viral or bacterial, but it’s part of the whole syndrome that coral around the world have been getting for the last several decades, and warm water exacerbates that,” he said.
Reed said the coral in Cuba may reveal a new way that nature is dealing with the threat. Coral might be seeking refuge in deeper water to avoid the warm water.
“Part of our hypothesis is that deeper reefs are a refuge,” Reed said. “The Keys are shallow but there are areas where the water is 60 meters, west of the Tortugas. It’s going to take us a year or two to analyze the data and come up with facts, and the biggest part of our analysis is the connectivity between Cuba and the Keys.”
The U.S. and Cuba in 2015 agreed to closer cooperation on environmental issues. The team observed several things that may warrant another trip around Cuba.
For example, several species of coral, plants and fish were spotted in depths beyond where they usually are found in comparable habitats.
Almost a quarter of Cuba’s coral reef is within that country’s Marine Protected Areas, which essentially creates a hands-off zone. During the expedition, the scientists noted four additional areas they say should receive the designation. They had higher fish populations and dense coral, which may indicate spawning zones.
“We took lots of dive notes and we’re trying to utilize what we learned to help protect these very vital ecosystems,” Reed said.