Florida reefs are in trouble. Could the answer lie in coral from the Caribbean?

Off the northern coast of Honduras, thick stands of endangered elkhorn coral have mysteriously defied warming oceans fueled by climate change to blanket the reef with healthy, cocoa-brown colonies branching toward the water’s surface like antlers.

Reefs near the small colonial town of Tela have more than three times the amount of live coral found elsewhere across the Caribbean.

Now scientists at the University of Miami Rosenstiel School hope to unlock that secret and crossbreed the sturdier coral with Florida elkhorn as they work to buy more time for a shrinking reef battered by rising ocean temperatures and disease.

“Usually we associate reefs with crystal clear water and lovely temperatures. These are rough, tough reefs,” said Andrew Baker, a Rosenstiel coral biologist leading the research. “There are enormous stands of elkhorn corals and great coverage of other corals. It's kind of a mystery why the corals are doing so well.”

In Florida, and around the planet, oceans absorb more than 90%of additional heat trapped by greenhouse gas. The extra heat is decimating reefs. Record heat last year triggered a global bleaching event, marking the second in just a decade. In Florida last summer, coral turned a ghostly white when a blistering heat wave caused them to spit out their life-sustaining algae and bleach.

With waters around the state hitting record highs again this summer, Baker and a team of students flew to Honduras in May to scout out what he hopes could become the parents of new, more resilient Florida coral.

At 4 a.m. one June morning they rose to be on the reef at daylight to collect the coral. Once packed in wet paper towels and sealed in bubble wrap, Baker and his team loaded the coral into six couch-sized coolers to be whisked back to Miami aboard a donated Amerijet cargo flight.

“It’s been a long day,” Baker said 14 hours later, standing on the tarmac at Miami International Airport waiting to clear customs as the evening sun turned the sky pink.

Baker’s biggest worry was temperature. Pilots set the cabin temperature to 77 degrees. But 14 hours is a long time, even for sturdy coral. Baker was confident the two species of brain coral would survive the trip, but he was less certain about the elkhorn.

“For those elkhorn corals, the ones we're actually most interested in, they are notorious for not traveling well,” Baker said.

Amerijet workers have shipped whales, dolphins, and even giraffes in the spacious Boeing 767 freighter jets but never coral. They quickly ferried the coolers through a warehouse as big as six football fields to a waiting truck for the half-hour drive to tanks outside Baker’s lab alongside Biscayne Bay.

Clouds of mosquitoes mobilized as the students and Baker unloaded the coolers for the moment of truth.

“All right, here we go,” Baker said as he cracked open the first cooler. “There's that smell.”

A sweet salty scent, like sea scallops, wafted out, signaling they’d survived being packed in a cooler for hours, bumped around on forklifts and jostled by airport workers.

Within a day, after most had acclimated to their new home, the coral were moved from the outdoor raceway tanks to an indoor spawning facility. Altogether 37 colonies of elkhorn and brain coral made the journey. To improve the chances for success, Baker gave seven elkhorn to the Florida Aquarium where scientists have been successfully breeding coral.

This is the first time coral have been brought into the U.S. to attempt breeding more resilient babies, Baker said. The idea of using foreign coral to do this has raised concern over mixing genetics. Still the concerns don’t outweigh what’s at stake: Elkhorn that once blanketed Florida reefs have nearly disappeared in the state. What remains was hit hard by last summer’s heat wave.

It took a year just to obtain permits to bring the coral into the U.S. , Baker said. If he succeeds at breeding them, he’ll need to secure more state and federal permits to plant them on Florida’s reef. Baker hopes to have the coral spawn in July or August, when Florida coral typically spawn. He can then cross-breed them and have babies growing while he works through the permitting process.

Baker ultimately hopes he can fasttrack an evolutionary process now being outpaced by climate change.

“We can't just wait for that solution to be ready and then think, ‘Okay, now what do we know now?’ What do we do to save these ecosystems?” he said. “We've got to work now, to have something left to save by the time we fix this bigger problem of climate change.”

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