May 23, 2017
View the original online at The Progressive
I first saw coral reefs and the abundance of life they generate as a teenager on a trip to Key West in 1967. Tropical reefs cover less than 1 percent of the ocean, but are home and nursery to 25 percent of all marine species; billions of fish, mollusks, and other creatures rely on reefs for food and shelter. Their vast beauty is generated by tiny living coral polyps, whose calcium carbonate skeletons build up bedrock structures over millennia.
Today, reefs generate huge tourism revenues for warm water nations and regions fringed by them. Their unique productivity also assures food security for hundreds of millions of people. Plus they act as storm barriers providing protection to coastal populations from South Florida to Indonesia at a time of rising sea levels and intensified hurricanes.
The Great Barrier Reef is the largest living thing visible from space. Stretching 1,400 miles along Australia’s northeast coast, it covers only one-tenth of 1 percent of the world’s ocean surface yet supports 8 percent of the world’s known fish species, about 1,500, plus more than 500 species of living coral: hard, soft, branching, and leafy.
I first dove Australia’s Great Barrier Reef in 1990, having dreamed about it since childhood. It was all I’d hoped for: warm, gin-clear waters vibrant with life, including giant potato cod (grouper), blue-green Napoleon wrasse, sharks, and multihued parrotfish crunching coral and excreting sand. There were canyons and bommies and walls with branching elkhorn, staghorn, plate, and fan corals. There were coral gardens in brown, green, red, pink, and purple, crevices full of moray eels and queen angelfish, and shelves of multiquill geisha-like lionfish along with red and blue spotted coral trout amidst a rainbow confetti of smaller fish, including clowns, damsels, sweetlips, chromis, and Moorish idols. The boulder-sized giant clams with their beautiful soft mantels of purple, green, and red algae-covered mollusk skin that opened like fat lips to the sea seemed to have calmed down considerably since my early TV viewing, when they trapped Sea Hunt’s Lloyd Bridges by the leg and tried to drown him.
The giant clams with their beautiful soft mantels of purple, green, and red algae-covered mollusk skin seemed to have calmed down considerably since I saw them on TV trapping Sea Hunt’s Lloyd Bridges by the leg and trying to drown him.
Sixty-seven percent of the reef segment north of Port Douglas is now dead rock. This latest coral die-off is the result of the third and most persistent global bleaching event since 1998; all are linked to fossil-fuel-fired climate disruption.
A new study that recently made the cover of the science journal Nature documents vast coral death along a 500-mile section of the reef. Where we took our dives, some patches are more than 80 percent gone. Other parts of the northern reef have seen less extreme die-offs, averaging 17 to 35 percent. Best estimates are that 22 percent of the total coral cover of the Great Barrier Reef is gone. Most marine scientists now believe 75 percent of the world’s coral reefs will be dead due to accelerating climate change by mid-century. Half are already gone.
Best estimates are that 22 percent of the total coral cover of the Great Barrier Reef is gone. Most marine scientists now believe 75 percent of the world’s coral reefs will be dead due to accelerating climate change by mid-century. Half are already gone.
“We didn’t expect to see this level of destruction to the Great Barrier Reef for another thirty years,” Terry P. Hughes, a co-author of the paper, told The New York Times, one of the few U.S. media outlets that have bothered to cover this global catastrophe. He also told the Times that, after reviewing some of their photos taken from low-flying aircraft, he and his graduate students began to cry in mourning. Chasing Coral, a new documentary appearing on Netflix, shows the die-off in stunning time-lapse imagery, including branching corals off New Caledonia that turned luminescent pink, orange, and blue, shining with a radiant light never before seen in the world, just before they died.
I saw my first bleached coral in Fiji in 2002 and my last in Hawaii in late 2015, where about one-third of the corals at Two Steps on the Big Island had turned wedding cake white. The diagnosis, symptoms, and disease mechanisms of coral bleaching are now well understood by science—despite Environmental Protection Agency chief Scott Pruitt’s claim that carbon-dioxide emissions are not a primary contributor to climate change. To understand a statement like that, it helps to know that the oil and gas industry has been a primary contributor not only to climate change and coral bleaching but also to Pruitt’s political career.
Corals, although able to form massive colonies, are counterintuitively delicate, requiring seven specific ocean conditions in which to thrive, including low-nutrient waters of a certain salinity that stay within a particular temperature range.
Ocean warming resulting from climate change, combined with cyclical warming caused by the weather system El Niño, causes the photosynthetic algae that give corals their varied colors and about 70 percent of their nutrients to turn toxic. The coral polyps then expel these zooxanthellae algae and begin turning white even as they continue to grab zooplankton out of the seawater flowing past them (zooplankton provide about 30 percent of their food stock). If ocean thermal conditions change, the coral can recover, but if the bleaching lasts too long, the corals slowly starve to death.
The report in Nature found that repeated exposure to bleaching did not make corals any more resistant to heat stress. Also, while efforts are underway to reduce other threatening impacts, including polluted runoff from coastal development and sugarcane fields, overfishing, and physical damage, the worst bleaching occurred in the least human-impacted northern stretch of the Great Barrier Reef, simply because a series of tropical storms had brought cooler water and relief to the more developed central and southern sections of the reef.
In the Florida Keys, where the coral barrier reef is one-tenth the size of Australia’s but gets ten times the visitors, a combination of all these factors has reduced the live coral cover from about 90 percent when I first snorkeled it at age fifteen to less than 10 percent today.
In more recent years, I’ve seen algae-covered rubble fields where coral gardens once thrived, and intricate fan corals shredded like Irish lace attacked by hungry moths where farm-soil Aspergillus fungus had washed into the sea. Today, Florida’s once common branching staghorn and elkhorn corals are on the U.S. endangered species list.
Yet another challenge for reef survival—along with bleaching, overfishing (which removes grazers like parrotfish that control algae growth), and runoff pollution—is ocean acidification.
To understand Scott Pruitt’s claim that carbon-dioxide emissions are not a primary contributor to climate change, it helps to know that the oil and gas industry has been a primary contributor not only to climate change and coral bleaching but also to Pruitt’s political career.
When I wrote my first ocean book, Blue Frontier, in 2001, climate scientists still didn’t understand why the atmosphere wasn’t heating up as rapidly as their computer models predicted. It was only in the following years that they realized that as much as a third of our anthropogenic (human-generated) carbon was being buffered by the ocean and converted into carbonic acid, shifting the global pH of the ocean and making it harder for shell-forming creatures, including certain planktons, clams, crabs, oysters, urchins, and, of course, coral, to pull calcium carbonate out of seawater to form their living homes.
Today, the ocean is about 30 percent more acidic than it has been for at least two million years. Among the first to feel the economic impact has been the shellfish industry, including companies like Taylor Shellfish Farms in Washington State and Hog Island Oysters in California, whose spat (baby oysters) can no longer survive in their local breeding waters.
So is there hope?
This past summer, I got to dive in the shark-enhanced (not infested) waters of Palau, which National Geographic Society Explorer-in-Residence Sylvia Earle calls one of the ocean’s “Hope Spots.” Palau, where 80 percent of that nation’s waters have been protected from fishing and other impacts, has avoided the worst of the recent reef bleaching. Its reef remains a healthy, robust ecosystem with most of its living biomass made up of large predators and grazers: schooling sharks, barracuda, sea turtles, jacks, manta rays, pilot whales, and titan triggerfish, one of whom gave me a good nip in the leg. Walking along a seawall in the capital of Koror state, eyeing the tropical fish, clams, and a baby sea snake, I was reminded of my youth in Key West.
Palau’s healthy reefs may also contain corals with genetic traits that help protect them against warming seas. That is why Steve Palumbi and a band of researchers will be visiting this summer. Palumbi is director of Stanford University’s Hopkins Marine Station in Pacific Grove, California, and one of the first marine scientists to use DNA sampling to better understand marine ecosystems. For the past eight years, he’s been sampling corals in American Samoa to see if there are not just physical but genetic differences that distinguish corals capable of tolerating warmer seas.
“Physiologically, your body adjusts to altitude making more red blood cells in Denver than at sea level,” he explains, “but then Tibetans also have the right genes for high elevation. So are there corals that are the Tibetans of the ocean? We found a tabletop coral like that, which is heat tolerant. When we did transplants [from hot spots] to cooler parts of the reef we found they retain about half their heat tolerance.”
Palumbi’s question about the Great Barrier Reef die-off is why 35 percent of the corals that stretch for 100 miles north of Port Douglas did not die. Even within the same species, corals that are not bleached sit next to those that are. Palumbi is interested in the process of natural selection that has generated this pattern of genetic diversity and resistance.
“We’ve never restored a reef, although we’ve known how to transport corals for a long time,” he says. “So if we’re going to go in that direction we have to look at things on land like forest restoration. That tells us we don’t start by taking clippings off existing trees—we start with a large nursery.” Such large-scale coral restoration work, he notes, would have to last decades—far longer than any existing restoration project.
In 2005, I saw an early attempt at coral restoration snorkeling at East Dry Rocks, six miles off Key West. The once-vibrant coral was now dead rock, with dozens of recently added concrete wheels where there were attempts to seed and grow elkhorn coral, with some success. Still, the experiment looked like a small English garden planted in a clear-cut forest.
Today, there are hundreds of attempts to grow and plant coral onto wild reefs. The Florida Aquarium recently announced a joint program with the National Aquarium of Cuba in which they’ve begun to grow more than 1,000 staghorn corals in an underwater nursery off the western tip of the island. Other restoration projects are underway in Jamaica, Colombia, Mexico, Honduras, Haiti, Hawaii, Australia, Mauritius, and elsewhere—all supported by governments, nonprofit groups, and a for-profit start-up called Coral Vita.
Today, there are hundreds of attempts to grow and plant coral onto wild reefs.
The largest effort is being carried out in Florida by the Coral Restoration Foundation based in Key Largo. The group is now out-planting 20,000 endangered elkhorn and staghorn corals a year, hoping to soon raise that number to 50,000.
“This is no longer a novel concept,” reef restoration program manager Jessica Levy told me. “We’re now working on twenty-seven reefs, so scalability is increasing. We have upwards of 300 genotypes, some more or less resistant to thermal stress, others to diseases and so on—since we don’t know which will work best in the future. Our aim is also to create low-cost techniques and easy-to-use materials for volunteers and companies and people living by the water. It’s going to take collaboration and lots of [grassroots] involvement to be successful in the long run.”
In 2015, the National Oceanic and Atmospheric Administration (NOAA) released a recovery plan under the Endangered Species Act. It said recovery of elkhorn and staghorn corals off Florida would require “active enhancement” (nursery-based out-planting) to succeed. More than $1 billion of NOAA funding for this kind of planning, research, and recovery is now targeted for elimination under the Trump budget, while the Republican Congress wants to gut the entire Endangered Species Act.
“If we do nothing, there’s no chance for recovery,” Levy explains. “But if you can actively work to restore these reefs, it keeps the system above water, so to speak, in the hope that things will change.”
Levy has a personal interest in the project. She is certified to dive the Great Barrier Reef. It was “devastating,” she says, to hear Terry Hughes report on his data, and to see the photos of the massive die-off.
Yet Levy sounds hopeful that the restoration work of her organization and others might help the Great Barrier Reef. “I’ve seen corals that we out-planted eight years ago at ten to fifteen centimeters that are now the size of large coffee tables,” she says. “They’re huge and have fish everywhere around them and continue to grow up and out like gangbusters, which is pretty awesome.”
Still, when it comes to the Great Barrier Reef and other massive reef systems that make up the coral heart of our blue planet, we’ve now reached the stage of triage. We have to save what we can in order to keep their genetic diversity and biological complexity alive for some hoped-for future revival, when humanity understands the value of ecosystem restoration. For now, it’s about protecting what my father, working with thousands of people who’d made it through the concentration camps in 1945 Berlin, called the Sh’erit ha-Pletah, “the surviving remnant.”
Or, as Steve Palumbi puts it, “Our chance and role is to keep as many things alive and in good shape as long as possible till we solve the problem of carbon dioxide.”
Under the current regime, the immediate need is reflected in a familiar adage: “If you find yourself in a hole, the first thing you should do is stop digging.”
View the original online at The Progressive