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  PlanetArk 11 Apr 06
Caribbean Reefs Ailing From Bleaching, Disease
Story by Jim Loney

National Geographic 6 Apr 06
Warming, Disease Causing Major Caribbean Reef Die-Off
Sean Markey for National Geographic News

ENN 4 Apr 06
Coral Die-Off Spreads to Caribbean
By Kevin Wadlow, Florida Keys Keynoter


ENN website 31 Mar 06
 Caribbean Coral Suffers Record Bleaching, Death
By Seth Borenstein, Associated Press

WASHINGTON: A one-two punch of bleaching from record hot water followed by disease has killed ancient and delicate coral in the biggest loss of reefs scientists have ever seen in Caribbean waters.

Researchers from around the globe are scrambling to figure out the extent of the loss. Early conservative estimates from Puerto Rico and the U.S. Virgin Islands find that about one-third of the coral in official monitoring sites has recently died.

"It's an unprecedented die-off," said National Park Service fisheries biologist Jeff Miller, who last week checked 40 stations in the Virgin Islands. "The mortality that we're seeing now is of the extremely slow-growing reef-building corals. These are corals that are the foundation of the reef ... We're talking colonies that were here when Columbus came by have died in the past three to four months."

Some of the devastated coral can never be replaced because it only grows the width of one dime a year, Miller said.

Coral reefs are the basis for a multibillion-dollar tourism and commercial fishing economy in the Caribbean. Key fish species use coral as habitat and feeding grounds. Reefs limit the damage from hurricanes and tsunamis. More recently they are being touted as possible sources for new medicines.

If coral reefs die "you lose the goose with golden eggs" that are key parts of small island economies, said Edwin Hernandez-Delgado, a University of Puerto Rico biology researcher.

On Sunday, Hernandez-Delgado found a colony of 800-year-old star coral -- more than 13 feet high -- that had just died in the waters off Puerto Rico.

"We did lose entire colonies," he said. "This is something we have never seen before."

On Wednesday, Tyler Smith, coordinator of the U.S. Virgin Islands Coral Reef Monitoring program, dived at a popular spot for tourists in St. Thomas and saw an old chunk of brain coral, about 3 feet in diameter, that was at least 90 percent dead from the disease called "white plague."

"We haven't seen an event of this magnitude in the Caribbean before," said Mark Eakin, coordinator of the National Oceanic and Atmospheric Administration's Coral Reef Watch.

The Caribbean is actually better off than areas of the Indian and Pacific ocean where mortality rates -- mostly from warming waters -- have been in the 90 percent range in past years, said Tom Goreau of the Global Coral Reef Alliance.

Goreau called what's happening worldwide "an underwater holocaust."

And with global warming, scientists are pessimistic about the future of coral reefs. "The prognosis is not good," said biochemistry professor M. James Crabbe of the University of Luton near London. In early April, he will investigate coral reef mortality in Jamaica.

"If you want to see a coral reef, go now, because they just won't survive in their current state."

For the Caribbean, it all started with hot sea temperatures, first in Panama in the spring and early summer, and it got worse from there. New NOAA sea surface temperature figures show the sustained heating in the Caribbean last summer and fall was by far the worst in 21 years of satellite monitoring, Eakin said.

"The 2005 event is bigger than all the previous 20 years combined," he said.

What happened in the Caribbean would be the equivalent of every city in the United States recording a record high temperature at the same time, Eakin said. And it remained hot for weeks, even months, stressing the coral. The heat causes the symbiotic algae that provides food for the coral to die and turn white. That puts the coral in critical condition.

If coral remains bleached for more than a week, the chance of death soars, according to NOAA scientists. In the past, only some coral species would bleach during hot water spells and the problem would occur only at certain depths.

But in 2005, bleaching struck far more of the region at all depths and in most species. A February NOAA report calculates 96 percent of lettuce coral, 93 percent of the star coral and nearly 61 percent of the iconic brain coral in St. Croix had bleached.

Much of the coral had started to recover from the bleaching last fall, but then the weakened colonies were struck by disease, finishing them off.

Eakin, who oversees the temperature study of the warmer water, said it's hard to point to global warming for just one season's high temperatures, but other scientists are convinced.

"This is probably a harbinger of things to come," said John Rollino, the chief scientist for the Bahamian Reef Survey. "The coral bleaching is probably more a symptom of disease -- the widespread global environmental degradation -- that's going on." Crabbe said evidence of global warming is overwhelming.

"The big problem for coral is the question of whether they can adapt sufficiently quickly to cope with climate change," Crabbe said. "I think the evidence we have at the moment is: No, they can't.

"It'll not be the same ecosystem," he said. "The fish will go away. The smaller predators will go away. The invertebrates will go away."

ENN 4 Apr 06
Coral Die-Off Spreads to Caribbean
By Kevin Wadlow, Florida Keys Keynoter

MARATHON, Fla.: The alarming scenario has spread to waters of Caribbean: Large coral colonies bleaching white, and then dying. Marine biologists in the Florida Keys have seen it already.

"The declines now being seen on reefs in the Virgin Islands and Caribbean are very similar to declines that have been seen on Keys reefs, caused by bleaching and disease," said Cheva Heck, information officer for Florida Keys National Marine Sanctuary. "It shows the problems are the same all over," Heck said. "It's not just the Keys, but the region and the world. We've heard reports from the Pacific, as well."

According to an Associated Press report, recent estimates from Puerto Rico and the U.S. Virgin Islands say that about one-third of the coral in official monitoring sites has recently died.

"It's an unprecedented die-off," said National Park Service fisheries biologist Jeff Miller, who last week checked 40 stations in the Virgin Islands. "The mortality that we're seeing now is of the extremely slow-growing reef-building corals," Miller said. "These are corals that are the foundation of the reef ... colonies that were here when Columbus came by have died in the past three to four months."

Sunday, Edwin Hernandez-Delgado, a University of Puerto Rico biology researcher, found a colony of 800-year-old star coral that towered more than 13 feet high had recently died in waters off Puerto Rico.

"We did lose entire colonies," he said. "This is something we have never seen before." Wednesday, Tyler Smith, coordinator of the U.S. Virgin Islands Coral Reef Monitoring Program, dived at a popular spot for tourists in St. Thomas and saw an old chunk of brain coral, about 3 feet in diameter, that was at least 90 percent dead from the disease called white plague.

"We haven't seen an event of this magnitude in the Caribbean before," said Mark Eakin, coordinator of the National Oceanic and Atmospheric Administration's Coral Reef Watch.

For the Caribbean, it all started with hot sea temperatures, first in Panama in the spring and early summer, and got worse from there. New NOAA sea-surface temperature figures show the sustained heating in the Caribbean last summer and fall was by far the worst in 21 years of satellite monitoring, Eakin said.

"The 2005 event is bigger than all the previous 20 years combined," he said. It remained hot for weeks, even months, stressing the coral. The heat causes the symbiotic algae that provides food for the coral to die and turn white. That puts the coral in critical condition. If coral remains bleached for more than a week, the chance of death soars, according to NOAA scientists.

In the past, only some coral species would bleach during hot-water spells and the problem would occur only at certain depths. But in 2005, bleaching struck far more of the region at all depths and in most species. February NOAA report calculates 96 percent of lettuce coral, 93 percent of the star coral and nearly 61 percent of the brain coral in St. Croix had bleached.

In 1997 and 1998, Keys waters suffered consecutive years with widespread coral bleaching, followed by an onset of diseases that caused a steep decline in the amount of living coral locally.

"It's something that concerns the sanctuary and we continue to monitor the situation," Heck said. "Our corals were starting to bleach heavily last year, but the waters cooled and the coral seemed able to recover.

"But we never had much of a winter, and we are concerned about the water temperatures as summer approaches." Source: Knight Ridder/Tribune Business News

National Geographic 6 Apr 06
Warming, Disease Causing Major Caribbean Reef Die-Off
Sean Markey for National Geographic News

Caribbean coral reefs are dying from disease at an alarming rate, according to scientists who monitor the ocean ecosystems.

Researchers say they have yet to gauge the full extent of the die-off. But at monitoring sites in the U.S. Virgin Islands more than 90 percent of the coral suffered bleaching.

Caribbean coral was weakened by unprecedented bleaching events following record warm water temperatures last year. Bleaching occurs when heat stress causes corals to expel their symbiotic, food-producing algae known as zooxanthellae, turning the reef's skeleton ghostly white.

While coral can recover from bleaching events, many weakened Caribbean reefs are now succumbing to a fatal coral disease known as white plague.

Average water temperatures in the eastern Caribbean last September were the highest they have been in a century, said Mark Eakin of the National Oceanic and Atmospheric Administration (NOAA).

Coral reefs in the Caribbean experienced more heat stress in 2005 than the past 20 years combined, said Eakin, who coordinates NOAA's Coral Reef Watch satellite monitoring program.

"This was the most devastating bleaching event that we've seen in the Caribbean," he said.

Record Bleaching

Jeff Miller, a National Park Service fisheries biologist based at Virgin Islands National Park in St. John, says the bleaching episode is the most extensive he's seen in 21 years of marine studies.

In Panama 70 percent of the corals at monitoring sites showed signs of bleaching, according to NOAA. In Mexico 40 percent showed bleaching, while in Texas coral bleaching at sample sites ranged from 35 to 100 percent. Reefs along the Florida Keys were mostly spared, thanks to Hurricanes Katrina and Rita, which circulated cooler waters into the area, Eakins says.

But reefs in the eastern Caribbean, including the U.S. and British Virgin Islands and Puerto Rico, were the most severely affected.

Last fall marine biologists in Puerto Rico reported that 42 coral species on some reefs had bleached. More recently, Miller says, colleagues there have seen coral colonies more than 800 years old die in a matter of weeks.

Miller says a colleague diving on a reef 10 miles (16 kilometers) from St. John was surprised to see die-offs caused by the disease occurring as far down as 90 feet (27 meters). "This mortality is occurring on many different species there, the very slow-growing, major reef-building species," he said. "And that's what makes it so dramatic and so alarming." Caroline Rogers is a U.S. Geological Survey (USGS) marine ecologist who has spent 22 years on St. John.

She said she recently dove near a 5-foot (1.5-meter) coral colony in Mayo Bay only to discover that "it is entirely dead now." The sight was shocking, she says. "That coral has undoubtedly been there for hundreds of years, and it died over the course of several weeks." "Corals live really close to their upper thermal limit, so small increases in temperature can have very devastating consequences," she said.

Rogers says the rapid die-off is particularly distressing, because some reef-building corals grow only the width of a dime in a year.

Declining Coral

Biologists fear the die-offs will further degrade coral reefs in the Caribbean, a region that by one estimate has already lost 80 percent of its coral cover over the last three decades.

"You're down to the point where you really can't afford to lose that much [more]," NOAA's Eakin said. Miller, the Park Service fisheries biologist, said that "the trickle-down effect of this [bleaching and die-off] is pretty devastating."

The loss of living coral reefs, which act as nurseries for countless fish and marine species, will adversely impact fisheries and biodiversity, Miller says. "If the reefs go away, these fish populations are irrevocably changed." "[The reefs'] state of health is not good," said Nancy Knowlton, a marine biology professor at the Scripps Institute of Oceanography at the University of California, San Diego.

"Reefs have collapsed catastrophically just in the three decades that I've been studying them in many places," she said. Knowlton, who also directs the Center for Marine Biodiversity and Conservation at Scripps, says different factors negatively impact reefs in different places.

In addition to large-scale threats such as coral disease, reefs suffer localized threats such as pollution runoff and damage caused by dynamite, boat anchors, and recreational divers.

Miller and other resource managers say local impacts are highly destructive and that regulating them may offer the best hope for protecting the world's remaining coral reefs in the near future.

PlanetArk 11 Apr 06
Caribbean Reefs Ailing From Bleaching, Disease
Story by Jim Loney

MIAMI - Deadly diseases are attacking coral reefs across the Caribbean Sea after a massive surge of coral bleaching last summer, a two-pronged assault that scientists say is one of the worst threats to the region's fragile undersea gardens.

The attack, which is killing centuries-old corals, is the result of unusually hot water across the Caribbean region that some scientists argue is a consequence of global warming.

Coupled with a recent bleaching event that whitened and weakened coral on Australia's Great Barrier Reef, the Caribbean epidemic has biologists fearing for the future of the habitats that serve as spawning grounds, nurseries, tourist attractions and, some believe, alarm systems for the health of the oceans.

A catastrophic loss of corals, which grow in vivid colonies often likened to flower gardens, could be a body-blow to the Caribbean islands' multibillion-dollar tourism industry, which sells scuba, snorkeling and fishing along with sun and sand.

The unprecedented assault started last summer with some of the highest water temperatures on record in the Caribbean, which caused coral to bleach from Panama to the Virgin Islands.

Hot water stresses corals, causing the tiny animals to expel their symbiotic algae, which give corals their bright colors. Scientists believe bleaching weakens corals, leaving them susceptible to disease. In some Caribbean locations, 90 percent of corals were bleached, according to reef monitors.

Coral can recover from bleaching when the water cools and the algae return to their hosts. But last year's bleaching event was followed by a devastating attack of black band disease, white plague and other ailments.

"It's one of the worst we've ever seen in the Caribbean," said Dr. Mark Eakin, coordinator of the US National Oceanic and Atmospheric Administration's Coral Reef Watch.

SITUATION COULD WORSEN

Researchers are uncertain how widespread the disease outbreak is and they fear it could get worse as the waters warm again this summer. Some preliminary observations in the British Virgin Islands show mortality of 20 percent to 25 percent, Eakin said.

In the US Virgin Islands, disease has killed some of the slow-growing corals, like brain and star corals, that build a reef's foundation, said Jeff Miller, a biologist with the National Park Service.

"At one of the study sites near St. John ... the preliminary results show about a 30 percent loss of coral cover," he said.

The Caribbean contains two of the longest reefs in the world -- the Belize reef, which ranks behind only the Great Barrier Reef, and the Florida Keys reef, which stretches beyond the length of the 110-mile (177-km) US island chain.

Billy Causey, superintendent of the Florida Keys National Marine Sanctuary, said bleaching was less severe on the Keys reefs because the area was hit by a swarm of hurricanes, which gain their power by drawing energy from warm sea water.

Divers have seen some plague and black band disease on the Keys reefs but it has caused less damage than on the Caribbean reefs, he said. While some scientists decline to link record high water temperatures to human-induced global warming because they have relatively few years of good records from which to draw conclusions, others are less reticent.

"I'm calling it heat stroke. I'm calling it an underwater nightmare," said marine pathologist James Cervino, a professor at Columbia and Pace universities. "If we don't control atmospheric CO2, we're putting the nail in the coffin right now," he said. "You're going to see isolated patches of sick, sorry corals, trying to hang on."
links
Caribbean Reefs Bleached by Warm Water By Associated Press ENN website 3 Nov 05
Related articles on Wild Shores of Singapore and Global warming
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