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(Bio) (Environment) Coral Reefs: Reefs Face Bleaching Risk

 
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PostPosted: Wed Feb 01, 2006 8:16 am    Post subject: (Bio) (Environment) Coral Reefs: Reefs Face Bleaching Risk Reply with quote






Australia's Reefs Face Bleaching Risk
By MIKE CORDER, Associated Press Writer
Tue Jan 31, 8:56 PM ET

A bout of coral bleaching hitting Australia's Great Barrier Reef could be as bad as an episode in 2001-2002 that affected 60 percent of the reef, scientists warned Tuesday.

An international team studying the world's reefs said in a statement that water temperatures for the past four months off Australia's northeastern coast have been well above long-term averages.

"We were all very concerned when we saw the temperature readings for December," said Prof. Ove Hoegh-Guldberg of the University of Queensland.

He said temperature measurements were similar to those in 2001-2002, which led to the worst coral bleaching ever recorded on the Great Barrier Reef.

"In that event, over 60 percent of the Great Barrier Reef bleached and up to five percent of reefs suffered serious damage," he added.

Hoegh-Guldberg chairs the Bleaching Working Group for the Coral Reef Targeted Research and Capacity Building for Management Program, a worldwide network of more than 100 scientists.

Coral bleaching occurs when the microscopic plants, or zooxanthellae, which live in coral tissue stop working due to stress that often is caused by rising temperatures. The zooxanthellae provide corals with color and food.

Coral reefs are not immediately killed by bleaching and if they are not severely stressed, they can recover their zooxanthellae and regain their color.

Bleaching already has whitened coral around the Keppel islands at the southern end of the Great Barrier Reef, a World Heritage-listed chain of reefs that stretches for almost 1,200 miles along most of the coast of Australia's Queensland state.

"Corals at the Keppels are completely bleached and we are only halfway through January," Hoegh-Guldberg said. "How this will develop across the Great Barrier Reef is the number one question right now."

Healthy coral is key to marine ecosystems along the reef and also to a multibillion dollar tourist industry in Australia, where the Great Barrier Reef is one of the top draws.

Paul Marshall, manager of the Great Barrier Reef Marine Park Authority's Climate Change Response Program, said that while most of the tourism is based around the northern stretches of the reef, there are reefs of ecological importance and several popular resorts around the southern reaches.

Marshall said there had been reports late last year of some bleaching in the north of the reef, but temperatures there had since dropped while in the south temperatures continued to be above average.

"We are going to be pretty lucky to escape coral deaths in the southern Great Barrier Reef," he said.

"It's going to have to be some pretty serious cloudy conditions to avert more serious bleaching down there," he added.

___

On the Net: http://www.gbrmpa.gov.au/

*************************************************************

Questions to explore further this topic:

A virtual coral reef adventure

http://www.coralfilm.com/virt.html

Slide shows

http://www.aote.org/menu/ss/index.htm

The Coral Reef (from Oracle's ThinkQuest)

http://library.thinkquest.org/J0112361/

Coral reef images database

http://life.bio.sunysb.edu/mar.....lreef.html
http://www.oceanfutures.org/Nemo/oceangallery.html
http://www.reefbase.org/dataphotos/dat_photos.asp
http://www.undersea.com.au/cor.....mation.htm

What are corals and coral reefs?

http://oceanworld.tamu.edu/stu.....coral1.htm
http://www.uvi.edu/coral.reefer/anatomy.htm
http://www.coris.noaa.gov/about/what_are/
http://www.coralfilm.com/about.html#overview
http://www.buschgardens.org/in.....chrcr.html
http://www.buschgardens.org/in.....natcr.html

How are corals classified?

http://www.buschgardens.org/in.....asscr.html

What are the different types of coral reefs?

http://www.uvi.edu/coral.reefer/structre.htm
http://www.coralfilm.com/about.html#types
http://www.buschgardens.org/in.....ralcr.html
http://www.reef.edu.au/contents/lt/fr_design.html
http://www.coris.noaa.gov/about/deep/

What are zooxanthellae?

http://www.uvi.edu/coral.reefer/zooxanth.htm
http://www.buschgardens.org/in.....aptcr.html

How do corals obtain food?

http://www.uvi.edu/coral.reefer/feeding.htm

What is symbiosis?

http://oceanworld.tamu.edu/stu.....coral3.htm

How do corals reproduce?

http://www.uvi.edu/coral.reefer/reproduc.htm
http://www.coris.noaa.gov/about/biology/
http://www.buschgardens.org/in.....procr.html

What are coral diseases?

http://www.uvi.edu/coral.reefer/disease.htm
http://www.coris.noaa.gov/about/diseases/

What is coral bleaching?

http://www.uvi.edu/coral.reefer/bleach.htm
http://www.reefbase.org/threats/thr_bleaching.asp
http://www.marinebiology.org/coralbleaching.htm

Presently, what are the threats to coral reefs?

http://www.uvi.edu/coral.reefer/threats.htm
http://www.coris.noaa.gov/about/hazards/
http://earthobservatory.nasa.g.....oral2.html
http://pubs.wri.org/pubs_conte.....tentID=654
http://www.reefbase.org/threats/thr_natural.asp
http://www.reefbase.org/threats/thr_human.asp
http://www.reefbase.org/threats/thr_climate.asp

Why are coral reefs important?

http://www.soc.soton.ac.uk/GDD...../menu.html
http://www.sheddaquarium.org/w.....article=37
http://www.uvi.edu/coral.reefer/animals.htm
http://www.buschgardens.org/in.....ecocr.html
http://oceanworld.tamu.edu/stu.....coral4.htm

Where are the coral reefs?

http://www.reefrelief.org/Coral%20Forest/map.shtml
http://www.buschgardens.org/in.....discr.html
http://www.reefbase.org/resour.....lreefs.asp

History of coral reefs

http://www.reef.edu.au/contents/lt/fr_origins.html

An online book on coral reefs

http://216.168.47.67/cis-fishnet/Crest/CRAA.htm

The Great Barrier Reef of Australia

http://www.nationalgeographic....../feature2/
http://www.barrierreefaustralia.com/

Coral reefs in the Philippines

http://www.earthdive.com/front.....sp?id=1406
http://newsroom.wri.org/newsre.....leaseID=14
http://marine.wri.org/pubs_con.....tentID=107
http://www.cyberdyaryo.com/fea.....113_01.htm
http://www.reefnet.org/issue3/constrat3.html

The following webpage ranks the Philippines as the number one reef hotspot (ranked according to degree of threat)

http://www.starfish.ch/reef/hotspots.html

The Philippines is mentioned in this article about coral reefs

http://oceanworld.tamu.edu/stu.....coral5.htm

GAMES

http://www.coralfilm.com/fun.html
http://www.oceanfutures.org/Nemo/mainlab.html
http://www.oceanfutures.org/Ne.....zzles.html


Last edited by adedios on Sat Jan 27, 2007 3:38 pm; edited 3 times in total
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PostPosted: Thu Feb 23, 2006 6:21 pm    Post subject: Coral Reef Discovered Off Thailand Coast Reply with quote

Coral Reef Discovered Off Thailand Coast
By MICHAEL CASEY, AP Environmental Writer
23 February 2006

A coral reef spanning several hundred acres and teeming with fish has been discovered off the coast of Thailand and should be given protected status, the World Wide Fund for Nature said Wednesday.

Tipped off by local fishermen, WWF divers in January found what they say is a healthy, 667-acre reef in southern Thailand with over 30 genera of hard corals, and at least 112 species of fish.

Among the fish species identified, the WWF said, was a type of parrot fish first discovered in Sri Lanka and never before seen in Thailand, and a species of the sweet lips fish previously only found in the Similan Islands.

The reef is off the coast of Khao Lak, a popular tourist destination on the Andaman Sea coast of Thailand.

"I believe discussions with fishermen over a wider area will lead us to discover even more important reefs, not yet mapped or protected by the authorities" said Songpol Tippayawong, head of the WWF Thailand Marine and Coastal Conservation Unit, in a statement.

"This reef is easily accessible to dive operators from nearby Khao Lak, and if managed properly can become a prominent local dive site while also contributing an important source of income to the local community," he said.

WWF said that it was working closely with Thailand's Department of Marine and Coastal Resources, the Department of National Parks, local communities and dive operators to ensure that the reef is properly managed, which could lead to it being included in a marine national park.

Sombat Poovachiranon, a marine biologist with the Department of Marine and Coastal Resources, said the reef was not on any of his department's maps.

"We are looking forward to doing a survey in the area," Sombat said. "It's quite a large area. In my opinion, this should be a marine protected area. But we have to talk to the local communities first."

The discovery is a dose of good news for the state of reefs, which have been battered by overfishing, development and more recently the 2004 tsunami, which heavily damaged them in Thailand, Indonesia, Sri Lanka and India.

A United Nations report in December found that close to a third of the world's corals have vanished, and 60 percent are expected to be lost by 2030. More than a third of all mangroves have disappeared, with the rate of loss greater than that of tropical rain forests, the report found.

A report released Monday from the Global Coral Reef Monitoring Network found that most coral reefs in the path of the December 2004 tsunami escaped "serious damage" and should recover in less than 10 years, though much will depend on local government's protecting marine ecosystems.

The report found that reefs in Indonesia, Sri Lanka, India and Thailand were hardest hit by massive waves with damage reaching up to 30 percent in some places. But much like earlier studies, it found that human activities like illegal fishing and climate change pose the greatest risk to the future of these reefs.
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PostPosted: Wed Apr 26, 2006 1:47 pm    Post subject: TINY POLYPS GORGE THEMSELVES TO SURVIVE CORAL BLEACHING Reply with quote

TINY POLYPS GORGE THEMSELVES TO SURVIVE CORAL BLEACHING
Ohio State University
26 April 2006

COLUMBUS , Ohio – Certain species of coral have surprised researchers by showing an unexpectedly successful approach towards survival when seriously bleached.

Their innovative strategy is gluttony.

The discovery, derived from experiments on coral reefs in Hawaii , provides new insights into how these tiny animals face a multitude of environmental threats. The report by Ohio State University researchers is published in the current issue of the British journal Nature.

During the past decade, reports have multiplied of major bleaching events that have damaged, if not destroyed, large portions of the world's fragile coral reefs. Scientists point to global warming as the cause and the victims are some of the tiniest creatures near the base of the undersea ecosystem.

Despite the apparent sturdiness of coral reefs, the creatures themselves are quite fragile. These tropical organisms survive in a narrow 4-to-6-degree C temperature range centered about 26 degrees C. While the exact temperatures vary with individual species from location to location throughout the tropics, they all must live within that tight range.

When the temperature climbs above that range, even by only two degrees, the result is a bleaching event. Within a two-year window during the 1997-98 El Nino event, 16 percent of the world's coral reefs sustained serious bleaching due to increases in seawater temperature and the animals died.


--------------------------------------------------------------------------------

Surprisingly, the researchers discovered that while the bleached Porites fed at its normal rate, bleached Montipora had increased its rate of feeding more than five-fold, allowing it not only to survive and repair but also replenish its internal energy reserves.
--------------------------------------------------------------------------------

“If the rain forests were dying off at this rate, we would all be panicking,” explained Andrea Grottoli, an assistant professor of geological sciences at Ohio State and lead author of the study.

“The problem is that now, with the planet's climate warming, coral are living closer and closer to their thermal threshold, so it takes less of a warming event than it did before to cause a catastrophe.”

Coral are symbiontic organisms that host one-celled algae within their bodies for mutual benefit. The coral polyp, a relative of jellyfish and anemones, provides a safe home within its cells for the algae while the algae convert sunlight into energy for the polyp.

Grottoli said that when the temperature of the waters around a reef exceeds that upper limit and stays there for more than two weeks or so, it triggers a bleaching event. Once that happens, the symbiotic algae and the brown or green photosynthetic pigments inside are lost. The result is a “bleached” white coral.

“In most cases, corals get 100 percent of their daily metabolic energy needs from the algae. Once they are gone, the coral polyp is left with only two alternatives: Draw energy from stored fats within its body, or eat organic matter and plankton in the surrounding water,” she said.

But what has puzzled Grottoli and other researchers is why in some bleaching events, some corals quickly died off while others close by were able to recover. To answer that, she returned to Hawaii Institute of Marine Biology where she has been studying corals for the past 13 years.

There, she and her collaborators focused on two types of common coral that thrived on the local reefs, Montipora capitata, or “rice” coral, and Porites compressa, “finger” coral. They collected samples of both types and placed them in sets of tanks supplied with natural seawater. Water from the reef was filtered to remove any plankton and flowed through the tanks in the same way it did through their natural environment. In one set of tanks, the water was heated, mimicking the rising temperatures leading to a bleaching event.

After a month, fragments of the coral were gathered from all of the tanks and put through a series of tests measuring energy reserves, photosynthetic rates and growth rates of the coral. The results showed that both Porites and Montipora used up their internal energy reserves. However, after a month of recovery on the reef (where plankton is naturally available) Porites continued to use up its reserves while Montipora had somehow managed to completely replenish them.

To explain that, Grottoli and colleagues closely examined the bleached and healthy corals of the two species on the reef.

“We let them feed for one hour,” Grottoli said. “Then we harvested them all, dissected each polyp and counted how many zooplankton each had eaten, how big they were and what species. That told us how much the coral had eaten.”

Surprisingly, the researchers discovered that while the bleached Porites fed at its normal rate, bleached Montipora had increased its rate of feeding more than five-fold, allowing it not only to survive and repair but also replenish its internal energy reserves.

“We think that this means that coral like Montipora can switch how it gets its food so that it can sustain itself in a bleached state much longer than can corals like Porites,” she said. “While bleached Porites is limited by how much energy reserves it has, bleached Montipora is not.

That's good news for Montipora and corals like it as the frequency, duration and intensity of warming events increases globally. But Grottoli warns that Montipora's resilience doesn't diminish the threat that bleaching events hold for the world's coral reefs. While it might survive while other species may not, on a global scale it is unlikely to re-colonize areas where less-resilient species died.

“Recent projections suggest that with the current rate of warming, as much as 60 percent of the world's coral reefs could be lost within the next 10 to 30 years,” she said. “We have a delicately balanced ecosystem that is already highly stressed. It is very much interconnected and so far, we have royally messed it up.”

Along with Grottoli, her graduate student Lisa J. Rodrigues, (now a postdoctoral fellow at Villanova University), and undergraduate student James E. Palardy, (now a PhD student at Brown University), also worked on the project. Support for this research came in part from the Andrew Mellon Foundation and the National Science Foundation.
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PostPosted: Mon May 15, 2006 4:51 pm    Post subject: Global warming may have damaged coral reefs forever Reply with quote

University of Newcastle upon Tyne
15 May 2006

Global warming may have damaged coral reefs forever


Global warming has had a more devastating effect on some of the world's finest coral reefs than previously assumed, suggests the first report to show the long-term impact of sea temperature rise on reef coral and fish communities.
Large sections of coral reefs and much of the marine life they support may be wiped out for good, say the international team of researchers, who surveyed 21 sites and over 50,000 square metres of coral reefs in the inner islands of the Seychelles in 1994 and 2005.

Their report is the first to show the long-term impact of the 1998 event where global warming caused Indian Ocean surface temperatures to increase to unprecedented and sustained levels, killing off (or 'bleaching') more than 90 per cent of the inner Seychelles coral.

The team, led by the University of Newcastle upon Tyne, and which comprises researchers from the UK, Australia and the Seychelles, publishes its findings today, Monday May 15, in the Proceedings of the National Academy of Sciences.

The research showed that, while the 1998 event was devastating in the short term, the main long-term impacts are down to the damaged reefs being largely unable to reseed and recover. Many simply collapsed into rubble which became covered by unsightly algae.

The collapse of the reefs removed food and shelter from predators for a large and diverse amount of marine life - in 2005 average coral cover in the area surveyed was just 7.5 per cent.

The survey showed that four fish species (a type of butterfly fish, two types of wrasses and a type of damsel fish) are possibly already locally extinct, and six species are at critically low levels (a type of file fish, three types of butterfly fish and two damsel fish), although their decline probably started to happen soon after 1998.

The survey also revealed that species diversity of the fish community had decreased by 50 per cent in the heavily impacted sites. Reduced biodiversity results in a more fragile and less stable ecosystem.

Smaller fish have reduced in number more quickly than larger species but their decreased availability has started to have a more lasting effect on the food chain, and this effect is likely to be amplified as time goes on. Moreover, the observed decrease in herbivorous fish is a key concern as they control algal spread.

Researchers speculate that the reefs' inability to reseed is down to their relative isolation. A lack of nearby reefs to provide larvae which could settle and grow into new coral structures and the absence of favourable sea currents to transport the larvae could be largely to blame.

Yet while a bleak picture is painted in the inner islands of the Seychelles, the survey area, from a diving perspective the outer carbonate islands still offer healthy coral reefs. Early results from diver tourist surveys in the inner islands suggest that diver satisfaction is high with granite reefs, wrecks and whale sharks.

Lead researcher Nick Graham, of Newcastle University's School of Marine Science and Technology, said: "We have shown there has been very little recovery in the reef system of the inner Seychelles islands for seven years after the 1998 coral bleaching event.

"Reefs can sometimes recover after disturbances, but we have shown that after severe bleaching events, collapse in the physical structure of the reef results in profound impacts on other organisms in the ecosystem and greatly impedes the likelihood of recovery.

"Unfortunately it may be too late to save many of these reefs but this research shows the importance of countries tackling greenhouse gas emissions and trying to reduce global warming and its effect on some of the world's finest and most diverse wildlife."


###
The team comprised researchers from the University of Newcastle upon Tyne, the Australian Institute of Marine Science in Townsville; the Centre for Environment, Fisheries and Aquaculture Science, Lowestoft; the Seychelles Centre for Marine Research and the Seychelles Fishing Authority.

The work was supported by grants from the British Overseas Development Administration (now DFID), the Leverhulme Trust and the Western Indian Ocean Marine Science Association.

MEDIA INFORMATION:

* THE EMBARGO:
This embargo is set by the Proceedings of the National Academy of Sciences, where the research is published.

INTERVIEWS: Mr Nick Graham, School of Marine Science and Technology, University of Newcastle upon Tyne.
Tel. +44 (0) 191 222 5868
Email: N.A.J.Graham@newcastle.ac.uk

PICTURES - for use by the media:

1. Healthy coral reef (NB this picture is not an image from the Seychelles)
http://www.ncl.ac.uk/press.off.....9Reef1.jpg

2. Dead reef in the inner Seychelles - the structure has not collapsed
http://www.ncl.ac.uk/press.off.....6Reef2.jpg

3. Dead and collapsed reef in the inner Seychelles (two pictures)
http://www.ncl.ac.uk/press.off.....7Reef3.jpg
http://www.ncl.ac.uk/press.off.....8Reef4.jpg

Six facts about coral reefs

1. Coral reefs are massive structures made of limestone that is deposited by living animals

2. They support over 25 per cent of all known marine species

3. They are home to over 4,000 different species of fish, 700 species of coral and thousands of other plants and animals

4. They are found in over 100 countries

5. Worldwide, they cover an estimated 284,300 square kilometres

6. They began growing as early as 50 million years ago but most established coral reefs are between 5,000 and 10,000 years old

Source: International Coral Reef Information Network Fact Sheet http://www.coralreef.org/

Source information: 'Dynamic fragility of oceanic coral reef ecosystems', Graham, N.A.J et all, Proceedings of the National Academy of Sciences. Copies available from Newcastle University Press Office.
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PostPosted: Thu Nov 23, 2006 8:16 am    Post subject: Coral reefs are increasingly vulnerable to angry oceans Reply with quote

University of California - Santa Barbara
22 November 2006

Coral reefs are increasingly vulnerable to angry oceans

Study predicts which corals are at greatest risk
(Santa Barbara, Calif.) –– Size and shape may predict the survival of corals around the world when the weather churns the oceans in the years to come, according to a new model that relies on engineering principles.

The increasing violence of storms associated with global climate change, as well as future tsunamis, will have major effects on coral reefs, according to a paper published this week in the international scientific journal Nature. Shape and size of the corals are key variables, according to the authors.

"Coral reef experts have long had a general sense of which coral shapes are more vulnerable during storms than others," said first author Joshua Madin, a scientist with the National Center for Ecological Analysis and Synthesis (NCEAS) at the University of California, Santa Barbara. "However, to really predict how these events impact the dynamics of coral reefs we needed a way to quantify these vulnerabilities."

The authors created the world's first engineering model to predict how much damage a reef is likely to suffer when confronted with the might of an angry sea. They used mathematical models to calculate the forces that coral is subjected to –– events such as waves, storm surges, or tsunamis –– and the probability of the colonies being ripped from the seabed.

Working with co-author Sean Connolly, Madin developed the model at the Centre of Excellence for Coral Reef Studies (CoECRS) at James Cook University, Australia. Connolly is also a senior lecturer at James Cook University.

How coral assemblages respond to the power of the sea is essential for understanding the natural distribution of coral types on present-day reefs as well as for projecting how they will change in response to more violent or frequent storms, according to the researchers.

"Our study offers a solution to this longstanding problem by factoring in the shape of different coral colonies, the strength of the sea-bed to which they attach, and the change in force of the waves as they move across the reef," said Madin. "This enables us to predict the likely changes in composition of the coral in response to present and future storms or tsunamis."

The researchers explained that managers can use this information to better understand how the world's coral reefs might change under a more unpredictable climate.

"The predictive tool we have developed allows managers to assess the vulnerability of their reefs to extreme wave events," said Madin. "The ability to estimate the potential damage on a reef for different disaster scenarios could help managers plan for economic losses as well as promote strategies to help the reef recover."

The researchers used mathematical models borrowed from engineering theory to translate the movement of storm waves into mechanical stresses on the coral in different parts of the reef, incorporating the various shapes of coral colonies, and then calculated whether or not they will be dislodged during extreme weather.

The study introduces a new concept, "colony shape factor," to translate the myriad shapes and sizes of coral colonies onto a simple scale that measures their vulnerability to being dislodged. Any severe event, like a hurricane, imposes a threshold that can be scored on the same scale, allowing scientists to determine which coral will live and which will die.

The scientists found that the most vulnerable corals are "table" corals, which have a broad flat top supported by a narrow stalk, making them more susceptible to strong wave forces than bushy or mounded corals. Vulnerability also depends on whether the coral grows on the front, crest, flat or the back of the reef, where the force of the waves progressively dies away.

The team ran a field test at Lizard Island, in the northern part of the Great Barrier Reef, taking digital photographs of corals, and calculating their vulnerability. They found that the threshold imposed by the previous year's biggest storm predicted the pattern of coral sizes and shapes almost perfectly.

"There were a lot of table corals present that went right up to the threshold from the last big storm, and then suddenly nothing above it," said Connolly. "They even followed the predicted trends from the reef crest to the reef back."

The researchers say that more severe storms, by themselves, would probably not pose a large threat to reefs. "Corals are adapted to life in stormy seas. Even the vulnerable species are quite stable when they're young," said Connolly. "They also tend to grow and mature quickly, so the species can recover before the next big storm arrives."

However, one effect of the increased production of greenhouse gases is an increase in the acidity of the ocean. This is likely to reduce the stability of coral reefs, and amplify the damage done by tropical storms in coming decades. Other effects of global warming could limit the capacity of the reefs to bounce back from periods of high wave forces, according to the researchers. For example, episodes of unusually hot temperatures can cause corals' cells to become toxic, or bleached. Another problem is overfishing, which can deplete the fish that eat dead coral and keep the reef clear for the next generation of corals.

"Regardless of whether we think of more severe storms as a looming threat or just the ramping up of a natural cycle, one thing is certain," said Connolly. "To predict how coral reefs will look under different future scenarios, and to plan accordingly, we needed to know exactly how wave forces impact who lives and who dies on the reef. These new models provide us with that essential tool."
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PostPosted: Wed Apr 11, 2007 8:45 am    Post subject: Ancient coral reef tells the history of Kenya's soil erosion Reply with quote

Stanford University
10 April 2007

Ancient coral reef tells the history of Kenya's soil erosion

Coral reefs, like tree rings, are natural archives of climate change. But oceanic corals also provide a faithful account of how people make use of land through history, says Robert B. Dunbar of Stanford University.

In a study published in the Feb. 22 issue of Geophysical Research Letters, Dunbar and his colleagues used coral samples from the Indian Ocean to create a 300-year record of soil erosion in Kenya, the longest land-use archive ever obtained in corals. A chemical analysis of the corals revealed that Kenya has been losing valuable topsoil since the early 1900s, when British settlers began farming the region.

For the full article:

http://www.eurekalert.org/pub_.....041007.php
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PostPosted: Wed May 16, 2007 9:04 am    Post subject: Investigating coral reefs to help understand past and future Reply with quote

16. May 2007 10:24
European Science Foundation

Investigating coral reefs to help understand past and future climate change

Increasing Earth temperatures and rising sea levels. Both of these are effects of climate change. The current concern is that human activity is changing our climate at a rate well above the natural climate cycling. Understanding how the Earth’s climate system works and responds to human impact is therefore of uttermost importance. “To predict future climate change we must first go back in the archives to understand a bit more about the natural cycles. This will enable us to decipher between natural changes and what’s out of the ordinary,” explained Gilbert Camoin, Centre National de la Recherche Scientifique (CNRS), at the European Geosciences Union (EGU) General Assembly in Vienna in April 2007.

The last deglaciation (23,000 – 6,000 years ago) is generally seen as a potential recent analogue for today’s environmental changes. This period was characterised by abrupt climatic change and rapid sea-level rise due to polar ice sheets melting, similar conditions to what we see the Earth facing now and which are predicted for the future. Reconstructing past environments may lead to a better estimate of the climate sensitivity and hence of future climate change.

Fossil coral reefs can be used to accurately reconstruct past sea level variations, climate change and environmental perturbations. According to Camoin, they provide the most precise records of sea-level changes. This is because corals always live within very strict ecological requirements. They need clear and oxygenated water, only live in the first 50m of the sea column, at temperatures ranging from 18-35 C and within the very narrow salinity range of 35-36 per ml. Any ecological changes affecting the narrow requirements of the coral reef environment will lead to changes in coral reef growth and composition. Thus, a fossil coral reef drill sample gives accurate information about the sea level, salinity and temperature at different times in history. Interpreting this information provides a way to reconstruct past climate change.

Using coral reefs as climatic archives started about 20 years ago. Initially, due to technical constraints, it was only possible to capture the last 10,000 years through coral reef drilling. To get datasets covering the entire period of the last deglaciation, it was crucial to find another technique. This became possible during a project where the Integrated Ocean Drilling Program (IODP) provided Camoin with the technology to drill down to 1100m recovering more than 600m of reef cores from 37 holes at depths ranging from 40 – 117m from the area around the island of Tahiti. Based on this initial success, the CHECREEF project was developed. CHECREEF is part of the European Science Foundation EUROCORES Programme EuroMARC. CHECREEF will look at data from both the Tahiti drilling site and an additional site in the Great Barrier Reef.

“We think that we will be able to reconstruct the sea level change going back 16-17,000 years in Tahiti and even further back in time in the Great Barrier Reef. With this we will be able to reconstruct sea surface temperature and salinity which are good indicators of the climatic changes at that time to see what happened to the reefs. We are pretty sure that we will achieve this goal within three years based on the datasets we have already collected,” said Camoin.

The two sites provide a good basis for creating a picture of past climate change. Firstly, they are away from the regions of the world covered by ice during the last ice age. Secondly, the core sites are located in the tropical pacific, a crucial point of the globe where many climatic anomalies are born e.g. El Nino. In addition, the two sites are located in zones which are tectonically quiet unlike volcanic islands and continental margins. This is the rational behind the CHECREEF proposal. However, Camoin goes on to say that to get a clear picture and a very good dataset, it is necessary to investigate other sites in the Indian Ocean and the Caribbean. This is Camoin’s plan for the future.

Camoin also highlighted that it is crucial to collaborate and compare the coral reef data with other techniques, from ice cores to ocean and lake sediments, to verify datasets.

“The project has just started and we are trying to get a good chronological frame to make sure where we are. The ice core records are well advanced and we will go back to compare our data to theirs in a year of two. We also have geophysical modellers waiting for our results to enter into their models,” explained Camoin.

Many of the European Science Foundation projects work towards understanding the Earth processes, both past and future. With its emphasis on a multidisciplinary and pan-European approach, the Foundation provides the leadership necessary to open new frontiers in European science.
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PostPosted: Sat Jun 02, 2007 7:40 am    Post subject: Slime Dwellers Reply with quote

Week of June 2, 2007; Vol. 171, No. 22 , p. 346

Slime Dwellers
A blanket seeded with microbes appears critical to coral health

Janet Raloff

Put on your snorkel gear and get close to coral—really close—and you can spy a thin layer of surface slime. Produced continually, and often in prodigious amounts, this mucus can be anything from a thick, soupy liquid to gummy gel. Corals expend significant energy making and replenishing these water-soluble jackets, but scientists have struggled to understand the payoff for this effort.

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http://sciencenews.org/articles/20070602/bob9.asp
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PostPosted: Wed Jun 06, 2007 1:41 pm    Post subject: Corals Show Recent Hurricane Spike Might Be the Norm Reply with quote

Corals Show Recent Hurricane Spike Might Be the Norm
By Andrea Thompson, LiveScience Staff Writer

posted: 06 June 2007 02:07 pm ET

The recent upsurge in the number of major Atlantic hurricanes may be the rule and not the exception, a new report suggests. The findings of this and other studies call into question recent assertions that global warming is behind the burst in hurricane activity seen since the mid-90s.

Between 1995 and 2005, an average of 4.1 major hurricanes (Category 3 or higher) were spawned over the Atlantic each year. But in the three decades before that, only 1.5 major hurricanes formed each year, according to National Oceanic and Atmospheric Administration records.

Some scientists have attributed the burst in hurricane activity over the past decade to rising sea surface temperatures caused by global warming, as warm waters can feed a growing storm.

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http://www.livescience.com/env.....ivity.html
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PostPosted: Thu Jun 21, 2007 7:21 am    Post subject: Herpes Virus Killing Coral Reefs Reply with quote

Herpes Virus Killing Coral Reefs
By Andrea Thompson, LiveScience Staff Writer

posted: 20 June 2007 09:16 am ET

NEW YORK—Corals get cold sores too. Only, for corals, a herpes virus infection isn’t just annoying. It can be lethal, and it and other diseases are possibly a big factor in the deaths of coral reefs that humans are causing throughout the world’s oceans, new research shows.

Scientists have known for years that humans are killing corals indirectly and directly through global warming, overfishing and pollution. Many reefs off populous coasts have been decimated, while those near uninhabited areas are often thriving.

“For some reason, when you put people next to reefs, they die,” said microbiologist Forest Rohwer of San Diego State University at a recent symposium at the American Museum of Natural History here.

A 2004 study found that 70 percent of the world’s reefs had been destroyed or were threatened by global warming and other human activities.

But just how these problems translate into a death sentence for corals has been difficult to work out.

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http://www.livescience.com/env.....orals.html
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PostPosted: Tue Jul 31, 2007 11:17 am    Post subject: Rare Sponge Found in Pacific Reply with quote

Rare Sponge Found in Pacific
By Andrea Thompson, LiveScience Staff Writer

posted: 31 July 2007 10:25 am ET

Reef-building glass sponges, thought until recently to be long extinct, have been found off the coast of Washington state, scientists announced yesterday.

Solitary glass sponges, so named because they are made of silica (the same material as beach sand and that is used to make glass), can be found living in many parts of the world's oceans, but they are different species than those that build themselves into reefs.

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http://www.livescience.com/ani.....onges.html
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PostPosted: Wed Aug 08, 2007 2:49 pm    Post subject: Coral Reefs Disappearing Faster Than Thought Reply with quote

Coral Reefs Disappearing Faster Than Thought
By Andrea Thompson, LiveScience Staff Writer

posted: 07 August 2007 08:39 pm ET

Coral reefs in the central and western Pacific are disappearing twice as fast as rainforests are on land—faster than was previously thought, a new study says.

The reefs in this region, called the Indo-Pacific, are disappearing at a rate of 1 percent per year—nearly 600 square miles of reef have disappeared per year since the late 1960s, researchers found.

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http://www.livescience.com/env.....cline.html
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PostPosted: Wed Sep 12, 2007 1:54 pm    Post subject: Corals added to IUCN Red List of Threatened Species for firs Reply with quote

Conservation International

Corals added to IUCN Red List of Threatened Species for first time

Climate change, over-fishing blamed for threats to marine life
Arlington, Virginia (Sept. 12, 2007) – For the first time in history, the IUCN Red List of Threatened Species includes ocean corals in its annual report of wildlife going extinct.

A comprehensive study of marine life sponsored by Conservation International (CI) and implemented jointly with the IUCN (World Conservation Union) used data from the Galapagos-based Charles Darwin Research Station and other regional institutions to conclude that three species of corals unique to the Galapagos Islands could soon disappear forever.

The 2007 IUCN Red List designates two of the corals – Floreana coral (Tubastraea floreana) and Wellington’s solitary coral (Rhizopsammia wellingtoni) – as Critically Endangered, while a third – Polycyathus isabela – is listed as Vulnerable. The Red List also includes 74 Galapagos seaweeds, or macro-algae, with 10 of them receiving the most threatened status of Critically Endangered. Prior to 2007, only one algae species had been included on the Red List.

“There is a common misconception that marine species are not as vulnerable to extinction as land-based species,” said Roger McManus, CI’s vice president for marine programs. “However, we increasingly realize that marine biodiversity is also faced with serious environmental threat, and that there is an urgent need to determine the worldwide extent of these pressures to guide marine conservation practice.”

The Galapagos marine research was conducted by the Global Marine Species Assessment (GMSA), a joint initiative of IUCN and CI launched in 2005 with the support of dozens of experts and research institutions. The GMSA is studying a large portion of Earth’s marine species to determine the threat of extinction.

“These Galapagos corals and algae are the first of many marine species that will be added to the Red List due to our findings,” said GMSA Director Kent Carpenter of Old Dominion University in Virginia. “What is significant is that climate change and over-fishing – two of the biggest threats to marine life – are the likely causes in these cases.”

Scientists blame climate change for more frequent and increasingly severe El Niño events that have caused dramatic rises in water temperatures and reduced nutrient availability around the Galapagos Islands in the Eastern Tropical Pacific Ocean, off South America. The warmer water harms corals and algae, both of which constitute the structural foundation of unique and diverse marine ecosystems.

Corals build reefs that are habitat for fish and other marine life, and also are a major attraction for divers in the Galapagos, where tourism makes a significant contribution to the local and national economy.

The recovery of algae species following strong El Niño events is harmed by over-fishing of the natural predators of sea urchins, which feed on the algae. Mushrooming urchin populations scour rocks clean of algae, depleting a major food source for other species such as the Galapagos marine iguana.

“Marine ecosystems are vulnerable to threats at all scales – globally through climate change, regionally from El Niño events, and locally when over-fishing removes key ecosystem building blocks,” said Jane Smart, head of the IUCN Species Program. “We need more effective solutions to manage marine resources in a more sustainable way in light of these increasing threats.”

Other coral and algae species lacked sufficient information to determine their IUCN Red List status, so they received the designation of Data Deficient. Researchers believe many of these species are likely to be listed as threatened with extinction when more detailed information becomes available.

The GMSA is the first strategic global review of the conservation status of marine species, including every marine vertebrate species and selected invertebrates and plants. Funded predominantly by CI, the five-year GMSA initiative is engaging experts from around the world to compile and analyze all existing information on the status of approximately 20,000 marine species to determine their risk of extinction according to the IUCN Red List Categories and Criteria. The resulting analysis will identify marine "hotspots" of high conservation priority in order to focus protection efforts on their habitats and species.
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PostPosted: Wed Oct 31, 2007 2:16 pm    Post subject: Coral reefs will be permanently damaged without urgent actio Reply with quote

University of Exeter
31 October 2007

Coral reefs will be permanently damaged without urgent action

Coral reefs could be damaged beyond repair, unless we change the way we manage the marine environment. New research by the Universities of Exeter and California Davis, published today (1 November 2007) in Nature, shows how damaged Caribbean reefs will continue to decline over the next 50 years.

Coral reefs conjure up images of rich, colourful ecosystems yet an increasing number of reefs are becoming unhealthy and overrun by seaweed. The research team wanted to test whether reefs that are overgrown with algae could return to good health if the original causes of the problem, such as fishing or pollution, were addressed. This could mean, for example, reducing fishing or introducing better sewage management. The study revealed that the answer is ‘no’ because coral reefs can become permanently unhealthy.

In the 1980s, reefs in the Caribbean were hit by the devastating impact of the near-extinction of the herbivorous urchin, Diadema antillarum, with devastating results. Along with parrotfish, this grazing urchin kept seaweed levels down, creating space for coral to grow. Parrotfish are now the sole grazers of seaweed on many Caribbean reefs, but fishing has limited their numbers. With insufficient parrotfish grazing, corals are unable to recover after major disturbances like hurricanes and become much less healthy as a result. The team discovered this result by creating and testing a computer model that simulates the effects of many factors on the health of Caribbean reefs.

Professor Peter Mumby of the University of Exeter, lead author on the paper said: “The future of some Caribbean reefs is in the balance and if we carry on the way we are then reefs will change forever. This will be devastating for the Caribbean’s rich marine environment, which is home to a huge range of species as well as being central to the livelihood of millions of people.”

The paper argues that in order to secure a future for coral reefs, particularly in light of the predicted impact of climate change, parrotfish need to be protected. Parrotfish are frequently caught in fish traps that are widely used in the Caribbean, with many ending up on restaurant diners’ plates.

Professor Peter Mumby continued: “The good news is that we can take practical steps to protect parrotfish and help reef regeneration. We recommend a change in policy to establish controls over the use of fish traps, which parrotfish are particularly vulnerable to. We also call on anyone who visits the Caribbean and sees parrotfish on a restaurant menu to voice their concern to the management.”


###
This research was funded by the US Environmental Protection Agency, the Royal Society, the Natural Environment Research Council and the National Science Foundation.
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PostPosted: Thu Nov 29, 2007 6:08 pm    Post subject: Wildlife Conservation Society study finds seasonal seas save Reply with quote

Wildlife Conservation Society
29 November 2007

Wildlife Conservation Society study finds seasonal seas save corals with 'tough love'

Reefs living in sites with variable temperatures better able to survive warm water

Finally, some good news about the prospects of coral reefs in the age of climate change. According to a new study by the Wildlife Conservation Society, corals may actually survive rising ocean temperatures in ‘tough love’ seas with wide-ranging temperatures.

Researchers discovered that coral reefs in sites with varying seasonal temperatures are more likely to survive the ‘hot pulses’ of Climate Change. Conversely, reefs living in environments with stable but higher temperatures are more susceptible to “bleaching,” a global phenomenon where beneficial algae are “evicted” by corals, ultimately leading to the reef’s demise.

The study, which appears in the latest edition of the journal Ecological Monographs, presents the results of an 8-year study on the reefs of East Africa.

“This finding is a ray of hope in a growing sea of coral bleaching events and threatened marine wildlife,” said Dr. Tim McClanahan, Senior Scientist working for WCS’ Coral Reef Programs and lead author of the study. “With rising surface temperatures threatening reef systems globally, these sites serve as high diversity refuges for corals trying to survive.”

Coral reefs are composed of tiny creatures that live in colonies in mostly tropical and subtropical waters. Corals are home to beneficial algae, which gives reefs their stunning colors. During prolonged, unusually high surface temperatures, many coral species bleach, discharging the algae and leaving the reefs white and sickly.

The study examined temperature variations and coral bleaching events off the coast of East Africa between the years of 1998 and 2005.

The researchers also discovered that the coral reefs in sites with the most temperature variation were in the ‘shadow’ of islands, protected from the oceanic currents that reduce temperature variations in reef ecosystems. According to the authors of the study, the results suggest that corals in these locations are better adapted to environmental variation. Consequently, they are more likely to survive dramatic increases in temperature.

“The findings are encouraging in the fact that at least some corals and reef locations will survive the warmer surface temperatures to come,” added McClanahan. “They also show us where we should direct our conservation efforts the most by giving these areas our highest priority for conservation.”

On a broader scale, the Wildlife Conservation Society engages in coral reef conservation on a global scale, with projects on reef systems in Belize, Indonesia, Papua New Guinea, Fiji, and Madagascar. All of these nations are island environments that may have similar persistence across the global warming crisis.
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PostPosted: Sat Dec 15, 2007 1:24 pm    Post subject: Increasing Acid Could Kill Most Coral by 2050 Reply with quote

Increasing Acid Could Kill Most Coral by 2050
By Andrea Thompson, LiveScience Staff Writer

posted: 13 December 2007 02:01 pm ET

SAN FRANCISCO — The world’s coral reefs face almost certain death as increasing amounts of carbon dioxide in the atmosphere are absorbed by the oceans, acidifying the water in which corals live, a new study warns.

In the past few decades, corals have come under increasing pressure from warming ocean waters, overfishing and disease. A recent study found corals in Pacific ocean were disappearing faster than previously thought.

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http://www.livescience.com/env.....-acid.html
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PostPosted: Fri Dec 21, 2007 5:35 pm    Post subject: Major international study warns global warming is destroying Reply with quote

December 13, 2007
Major international study warns global warming is destroying coral reefs and calls for 'drastic actions'
By Susan Lang

If world leaders do not immediately engage in a race against time to save the Earth's coral reefs, these vital ecosystems will not survive the global warming and acidification predicted for later this century. That is the conclusion of a group of marine scientists from around the world in a major new study published in the journal Science on Dec. 13.

"It's vital that the public understands that the lack of sustainability in the world's carbon emissions is causing the rapid loss of coral reefs, the world's most biodiverse marine ecosystem," said Drew Harvell, Cornell professor of ecology and evolutionary biology and head of the Coral Disease Research Team, which is part of the international Coral Reef Targeted Research (CRTR) group that wrote the new study.

The rise of carbon dioxide emissions and the resultant climate warming from the burning of fossil fuels are making oceans warmer and more acidic, said co-author Harvell, which is triggering widespread coral disease and stifling coral growth toward "a tipping point for functional collapse."

The 17 marine scientists who authored the new study argue that "drastic action" is needed from world leaders to turn around the trend in rising levels of atmospheric carbon dioxide (CO2) to protect coral reefs. They based their conclusions on the forecasts for rising global temperatures and levels of CO2 announced recently by the Intergovernmental Panel on Climate Change, a United Nations body.

"Coral reefs have already taken a big hit from recent warm temperatures, but rapid rises in carbon dioxide cause acidification, which adds a new threat: the inability of corals to create calcareous skeletons," said Harvell. "Acidification actually threatens all marine animals and plants with calcareous skeletons, including corals, snails, clams and crabs. Our study shows that levels of CO2 could become unsustainable for coral reefs in as little as five decades."

In the short term, better management of overfishing and local stressors may increase resilience of reefs to climate threats, but rising global CO2 emissions will rapidly outstrip the capacity of local coastal managers and policy-makers to maintain the health of these critical ecosystems if the emissions continue unchecked, the authors stress.

At stake, added Ove Hoegh-Guldberg, director of the Center for Marine Studies at the University of Queensland, Australia, and the study's senior author, are ecosystems that play vital roles in providing habitats for a vast array of marine species that are essential to the oceans' complex food chain. They also provide livelihoods to 100 million people who live along the coasts of tropical developing countries. Diving tourism in the Caribbean alone is estimated to generate more than $100 billion a year. The loss of coral reef ecosystems also is exposing people to flooding, coastal erosion and the loss of food and income from reef-based fisheries and tourism, he added.

The CRTR is a leading international coral reef research initiative that provides a coordinated approach to credible, factual and scientifically proven knowledge for improved coral reef management. It is a partnership of the Global Environment Facility, the World Bank, the University of Queensland, Australia, the U.S. National Oceanic and Atmospheric Administration and approximately 40 research institutes and other third parties around the world.
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PostPosted: Fri Dec 28, 2007 10:21 am    Post subject: Concern Lingers on Success of Artificial Reefs Reply with quote

Concern Lingers on Success of Artificial Reefs
By Charles Q. Choi, Special to LiveScience

posted: 27 December 2007 09:52 am ET

Artificial reefs made of everything from oil rigs to subway cars to concrete rubble are sunk these days to the ocean floor to provide homes for marine life. But are they actually helpful?

Although such reefs have at times done more harm than good, scientists explained artificial reefs are getting better and better.

For the full article:

http://www.livescience.com/env.....-reef.html
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PostPosted: Wed Jan 09, 2008 11:37 am    Post subject: Humans have caused profound changes in Caribbean coral reefs Reply with quote

Census of Marine Life
8 January 2008

Humans have caused profound changes in Caribbean coral reefs
Reports a study published in the Proceedings of the Royal Society of London B

Coral reefs in the Caribbean have suffered significant changes due to the proximal effects of a growing human population, reports a study published in the Proceedings of the Royal Society of London, B.

“It is well acknowledged that coral reefs are declining worldwide but the driving forces remain hotly debated,” said author Camilo Mora at Dalhousie University, Halifax, Canada. “In the Caribbean alone, these losses are endangering a large number of species, from corals to sharks, and jeopardizing over 4 billion dollars in services worth from fisheries, tourism and coastal protection,” he added.

“The continuing degradation of coral reefs may be soon beyond repair, if threats are not identified and rapidly controlled,” Mora said. “This new study moves from the traditional localized study of threats to a region-wide scale, while simultaneously analyzing contrasting socioeconomic and environmental variables,” he added.

The study monitored coral reefs, including corals, fishes and macroalgae, in 322 sites across 13 countries throughout the Caribbean. The study was complemented with a comprehensive set of socioeconomic databases on human population density, coastal development, agricultural land use and environmental and ecological databases, which included temperature, hurricanes, productivity, coral diseases and richness of corals. The data were analyzed with robust statistical approaches to reveal the causes of coral reef degradation in that region.

The study showed clearly that the number of people living in close proximity to coral reefs is the main driver of the mortality of corals, loss of fish biomass and increases in macroalgae abundance. A comparative analysis of different human impacts revealed that coastal development, which increases the amount of sewage and fishing pressure (by facilitating the storage and export of fishing products) was mainly responsible for the mortality of corals and loss of fish biomass. Additionally, the area of cultivated land (a likely surrogate for agrochemical discharges to coral reefs) was the main driver of increases in macroalgae. Coral mortality was further accelerated by warmer temperatures.

“The human expansion in coastal areas inevitably poses severe risks to the maintenance of complex ecosystems such as coral reefs,” Mora said. “On one hand, coral reefs are maintained due to intricate ecological interactions among groups of organisms. For instance, predators prey upon herbivorous, herbivores graze on macroalgae, and macroalgae and corals interact for their use of hard substrata. Given the intensity of these interactions the effects of a threat in anyone group may escalate to the entire ecosystem. On the other hand, the array of human stressors arising from changes in land use, exploitation of natural resources and increases in ocean temperature (and perhaps acidification) due to an increasing demand for energy, are significantly affecting all major groups of coral reef organisms. The simultaneous effect of human threats on coral reef organisms and the potential escalation of their effects to the entire ecosystem highlight the critical situation of coral reefs and the need to adopt an ecosystem-based approach for conservation and an integrated control of multiple human stressors,” he added.

The study also showed that the effective compliance of fishing regulations inside Marine Protected Areas (MPAs) has been successful in protecting fish populations. But coral mortality and macroalgae abundance showed no response to the presence of MPAs. That was explained by the general failure of MPAs in the Caribbean to account for threats such as land runoffs and ocean warming. “Unfortunately, the degradation of the coral reef matrix inside MPAs may, in the long term, defeat their positive effect on fish populations,” Mora said. “This further highlights the need for a holistic control of human stressors,” he added.

“The future of coral reefs in the Caribbean and the services they provide to a growing human population depend on how soon countries in the region become seriously committed to regulating human threats”, Mora said. “Although coral reefs will experience benefits of controlling fishing, agricultural expansion, sewage or ocean warming, it is clear that underlying all these threats is the human population. The expected increase of the world’s human population from 6 billion today to 9 billion for the year 2050 suggests that coral reefs are likely to witness a significant ecological crisis in the coming half century if effective conservation strategies, including policies on population planning, are not implemented soon,” he added.
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PostPosted: Mon Jan 14, 2008 1:59 pm    Post subject: Starfish outbreak threatens corals Reply with quote

Wildlife Conservation Society

Starfish outbreak threatens corals

NEW YORK (January 14, 2008) – Outbreaks of the notorious crown of thorns starfish now threaten the “coral triangle,” the richest center of coral reef biodiversity on Earth, according to recent surveys by the Bronx Zoo-based Wildlife Conservation Society and ARC Centre of Excellence for Coral Reef Studies.

The starfish – a predator that feeds on corals by spreading its stomach over them and using digestive enzymes to liquefy tissue – were discovered in large numbers by the researchers in reefs in Halmahera, Indonesia, at the heart of the Coral Triangle, which lies between Indonesia, Malaysia, the Philippines, Papua New Guinea and the Solomon Islands. It is considered the genetic fountainhead for coral diversity found on Australia’s Great Barrier Reef, Ningaloo and other reefs in the region.

Scientists fear the outbreak is caused by poor water quality and could be an early warning of widespread reef decline.

Recent surveys of Halmahera by the Wildlife Conservation Society and ARC Centre of Excellence for Coral Reef Studies confirmed that while Halmahera’s reefs are still 30-50 percent richer than nearby reefs, some areas were almost completely destroyed.

“The main cause of damage to the corals was the Crown of Thorns Starfish,” Dr. Andrew Baird of the ARC Centre of Excellence for Coral Reef Studies and James Cook University. “We witnessed a number of active outbreaks of this coral predator. There was little to suggest that the reefs have been much affected by climate change as yet: the threats appear far more localized.”

The team also saw first-hand evidence of recent blast-fishing, an extremely destructive fishing practice that uses explosives. According to locals this accompanied a break down of law and order following communal violence in 2000-2003. During the same time many reef lagoons were mined of their corals for use in construction, an activity encouraged by the Indonesian military.

“This is clearly a complex human environment and effective management of the marine resources must address the needs of communities. It will also be vitally important to understand the causes of conflict among communities and address them,” says Dr Stuart Campbell, Program Leader for the Wildlife Conservation Society’s’ Marine Program in Indonesia.

The researchers pointed out that there were still healthy populations of certain species – and still time to reverse the damage.

“The good news is that the reef fish assemblages are still in very good shape” said Tasrif Kartawijaya from WCS-IP. “We saw Napoleon wrasse and bumphead parrot fish at almost every site. So these reefs have the capacity to recover if we can address the current threats.”

The Coral Triangle Initiative (CTI) announced by six regional governments at the Bali Climate Change Conference recently offers hope for the reefs in the region, the researchers say. However, there are few details of how it will work and no mention of the fundamental role of research in the conservation program.

“We are disappointed research is yet to be fully considered in the CTI. The success of large marine parks, like the Great Barrier Reef Marine Park, is largely due to the primary role of science plays in understanding what’s going on, so managers can make good decisions,” said Dr Baird.

“It isn’t enough just to document the diversity of the region. Large scale research is required to understand the Coral Triangle ecosystems and work out how best to respond to threats such as poor water quality and overexploitation,” Dr Campbell added.
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PostPosted: Sun Jul 13, 2008 3:50 pm    Post subject: Not-OK Coral Reply with quote

Not-OK Coral
By Susan Milius
July 10th, 2008

Full review of status finds a quarter of reef-building species in peril

At least a quarter of the planet’s reef-building corals face a noticeable risk of extinction, according to the first large scale review of hundreds of species.

For the full article:

http://sciencenews.org/view/ge.....t-OK_Coral
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