ShareThis Page

Catastrophic period for coral reefs appears to be ending

| Monday, June 19, 2017, 9:36 p.m.
An undated handout photo obtained from the XL Catlin Seaview Survey on March 21, 2016 shows a diver filming a reef affected by bleaching off Lizard Island in the Great Barrier Reef.
AFP/Getty Images
An undated handout photo obtained from the XL Catlin Seaview Survey on March 21, 2016 shows a diver filming a reef affected by bleaching off Lizard Island in the Great Barrier Reef.

A worldwide wave of coral bleaching, which transformed colorful coral structures into lifeless skeletons, appears to be ending.

The National Oceanic and Atmospheric Administration announced Monday that satellite data and modeling indicated that a three-year period of coral bleaching has stopped after causing extensive damage to the world's coral reefs.

In coral bleaching, corals eject the tiny bits of algae that provide them with nutrition and that create the streaks of red, green and orange that characterize these vivid undersea environments. Bleaching weakens corals, making them vulnerable to disease.

In South Florida, scientists witnessed the death of a car-size, 300-year-old coral off the coast of Hollywood. And the bleaching appears to have killed about 95 percent of a species called pillar coral, weakening them sufficiently for disease to finish them off, said Mark Eakin, NOAA Coral Reef Watch coordinator.

“We've had an almost complete loss of pillar coral,” he said. “They're an absolutely gorgeous growth. It almost looks like the ruins of an old Greek building.”

Coral reefs provide homes for a vast range of fish, crabs, sponges and other marine creatures. In South Florida, which has the only coral reefs in the continental United States, they are a major tourist attraction, supporting jobs in fishing, diving and snorkeling.

NOAA blamed global warming and El Nino - the periodic warming of the Pacific Ocean off South America - for the bleaching that began in 2014.

But now, satellites show that corals are getting some relief from high ocean temperatures that caused bleaching.

“After analyzing satellite and model data, NOAA's experts say coral reefs around the world may finally catch a break from high ocean temperatures that have lingered for an unprecedented three years, the longest period since the 1980s,” a news release from NOAA said.

In past decades, El Nino has been blamed for coral bleaching. But Eakin said climate change has raised ocean temperatures to the point that it took just a small push from an El Nino to tip the world into another wave of bleaching.

Brian Walker, research scientist at Nova Southeastern University, said the diseases harming South Florida's corals have not subsided.

“Presumably a cooler summer might help the corals fight off the disease better, but it has been lethal so far even into the cooler months,” he said.

There was some good news, he said. Rare staghorn corals, which established dense patches off Fort Lauderdale in recent years, have been unaffected by the bleaching, he said.

NOAA says another bleaching may start this summer for U.S. reefs.

“Despite what appears to be the end of the third global event, some U.S. coral reefs are still not completely in the clear,” NOAA said. “NOAA's four-month coral bleaching outlook shows some risk to coral reefs in Hawaii, Florida and the Caribbean later this summer.”

Compounding the problem for South Florida's reefs, which stretch from the Florida Keys through Martin County, are the variety of stresses that come from living next an urban area, with coastal construction, dredging and the runoff of fertilizers and pesticides into the ocean.

“There are two things we need to be doing,” Eakin said. “We need to get climate change under control and we need to address the local stressors, and neither is going to be sufficient without the other.”

TribLIVE commenting policy

You are solely responsible for your comments and by using you agree to our Terms of Service.

We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.

While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.

We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers

We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.

We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.

We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.

We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.