I found this thread on another forum and am wondering if coral bleaching is becoming noticeable in Bonaire.

http://dive.scubadiving.com/talk/read.php?1,56507,56507#msg-56507

The link does not work, so here is the article.

Mark Meredith
Sunday, October 23rd 2005

Coral reefs across the Caribbean are undergoing a mass bleaching event which threatens life below and above the water.

In the last month, coral reefs across the Caribbean have become affected by a sudden and life-threatening bleaching epidemic brought on by sea temperature rise; the same temperatures which have unleashed a record 12 hurricanes on the region this season. Should the affected corals not recover, the long-term consequences for the Caribbean could be far more "devastating" than any number of storms.

Beneath Tobago's blue waters, out of sight and out of mind, death stalks the wondrous creations that are the island's coral reef systems. Marine cities more complex and beautiful than anything imagined on land, but which are essential to Tobago's terrestrial sustainability, are in the throes of a creeping, ghostly and possibly fatal plague-a White Death.

"Tobago's coral reefs are currently experiencing their worst mass bleaching event for many years and, according to some dive operators, the worst in living memory."

That was the warning from Dr Owen Day of the Buccoo Reef Trust last week, a few days after he had issued an alert over the internet to conservation groups and individuals requesting help in monitoring the growing coral crisis along Tobago's leeward coast, from Speyside to Crown Point.

Even more alarming was his revelation that bleaching is being reported over "the entire Caribbean region", affecting vast swathes of coral communities, including those in Panama, Cuba, Puerto Rico, Florida and Barbados. The Bajan situation was said to be "terrible".

Dr Hazel Oxenford, Senior Lecturer at the Centre for Resource Management and Environmental Studies (CERMES) at the University of the West Indies Cave Hill Campus in Barbados, told me: "We are seeing bleaching of almost all coral species on all reefs. The values (affected areas) are around 65-70 per cent for our deep reefs and up to 86 per cent for shallow reefs. Water temperatures are exceptionally high at depth and have been in excess of 30oC, even at 22 metres deep."

Owen Day, who has been personally monitoring Tobago's sea temperatures and videoing horrific scenes of an alien transformation of the rainbow-hued coral sculptures, told me: "The sea surface temperatures have been about two degrees above average for the time of year. In the last 20 years, the dramatic increases in the reported incidences of mass coral bleaching events has been undisputable. I can't understand why the international media hasn't picked up on this," he said of the Caribbean's current crisis.

In Tobago the bleaching started with fire corals losing their vibrant warning colours in early September. A few weeks later it spread to the brain corals and in October began crossing to new species, affecting many different varieties. Day said reefs on the Caribbean coast "seem particularly badly affected", notably Buccoo Reef, Mt Irvine, Arnos Vale, Culloden, Castara and Englishman's Bay. The reefs at Speyside and south of Crown Point are also showing signs of bleaching, he added. Corals appear to be affected down to a depth of about 50 feet.

When coral bleaches it does the same as your laundry and turns "brilliant white". It occurs because of environmental stress, said Day; specifically, "high or low temperatures, sediment, excessive sunlight, exposure to air, freshwater or pollutants".

Think of bleaching as the coral equivalent of HIV/AIDS: species weakened and highly vulnerable to stresses and infections. When the phenomenon happens, said Day, the corals expel their symbiotic microscopic algal cells (zooxanthellae) in response to the environmental stress. The condition turns coral colonies white as their calcium carbonate skeletons become visible through their unpigmented tissue (bleached). Day explained that zooxanthellae typically provide the coral with around 90 per cent of the energy required for a healthy life, the remaining 10 per cent being obtained from mostly nocturnal filter feeding.

But unlike today's terrestrial AIDS patients, there are no life-prolonging wonder drugs available for corals, only a death sentence once the sources of the stresses persist for more than about eight to ten weeks or so, said Day. The exact length of time it takes before they die is dependent on various factors, such as the severity of the bleaching, the type of coral species, and the depth at which they live. Corals can recover once favourable conditions return in time.

Day pointed out that this week's heavy swells through the Caribbean will have resuspended the sediment in the seawater, brought there by unsustainable land practices. When corals are bleached they are unable to produce the mucous needed to clean themselves, and they die beneath their newly-settled, grainy blanket.

They also need sunlight to survive, but that becomes temporarily filtered out by swirling silt clouds in such conditions. Cloudy water through tidal action is also exacerbated by the rainy conditions that accompany weather systems: surging outflows of silt and polluted run-off from the land.

The importance and fragility of coral reefs cannot be overstated: they cover just 0.02 per cent of our planet's entire ocean floor-but a quarter of all known marine species call them home. A reason, no doubt, why Dr Oxenford was "very happy" someone was reporting this "Caribbean-wide mass bleaching event".

She told me: "It certainly will have some devastating consequences if the coral we are seeing bleached now, does not recover. We are hoping against hope that it will, but the longer it remains bleached the greater the chance of widespread coral mortality.

"Of course, if the living hard corals die, then the reef structures (built by living hard corals) will continue to erode without repair and will become less and less effective in protection of our coastlines, production of white sand for our beaches, and in harbouring a myriad of coral reef fish species, many of which are of commercial importance to fisheries," she said.

"The economic consequences will be severe-with huge implications for tourism (loss of beaches, loss of quality snorkelling and diving); for coastal property owners (reduced natural protection, coastal erosion, loss of beach sand); and for fishers (loss of livelihood for coastal reef fishers). There will also be a loss of recreational opportunity and aesthetic value; a huge loss in biodiversity and increased vulnerability to other impacts of climate change such as sea level rise and increased severity of storms,"she warned.

Well before this bleaching event became evident, the stresses to Caribbean coral reefs had already become a wholly Caribbean-made epidemic through human activities; specifically, "land-based sources of pollution", often from the very tourism industry that profits from such attractions.

The Washington-based World Resources Institute have a map of threatened Caribbean reefs. The threat levels are illustrated as orange for "high" and red for "very high". The overall impression is of a region with coastlines painted like sunsets.

Two thirds of Caribbean coral reefs are under threat from humans, said the Institute in their 2004 publication "Reefs at Risk in the Caribbean". They advised: "Coral reefs are extremely important to the economies of Caribbean countries today, and they are the capital stock for future economic and political security ... Ensuring the vitality of the coral reefs and their ability to continue providing benefits to society is critically important ."

The Institute also warns of overfishing, leading to a change in the reefs' ecological balance; and of "poorly understood coral diseases that have spread rapidly throughout the region, devastating some of the main reef-building corals".

Many scientists concur that the major cause of bleaching is not Caribbean-made at all. It is the global pandemic to end all pandemics-Climate Change-in this case abnormal sea temperatures. While Caribbean nations alone cannot halt Climate Change, they can lessen the chances of the AIDS-like bleaching condition from becoming terminal , preventing land-based sources of pollution.

"Barbados is very aware of the importance of its reefs," said Oxenford. "It's put a great deal of effort (and money) over the last decade or so into mitigation of negative impacts on coastal water quality to ensure coral reef health. This includes sewage treatment, strict coastal building practices, effluent standards, and watercourse/coastal zone management."

"Also, direct protection is given through fisheries legislation which makes coral harvesting illegal island wide, and forbids the use of destructive fishing practices such as dynamite and use of toxins. Other efforts include the installation of mooring buoys and designated anchoring areas to prevent physical damage.

Like most islands, "improved agricultural practises to prevent soil erosion and pesticide contamination, and better drainage management to prevent land water runoff, needed attention", she added.

In Tobago's case, the Buccoo Reef Trust (BRT) isn't prepared to wait for the life-enhancing, self-administered medicine the island needs to save itself. It has formed an alliance with UK-based Coral Cay Conservation (CCC), a non-profit organisation based in the UK with "extensive experience in coral reef monitoring worldwide". They have offered to send out a team of four experienced divers to Tobago in mid-October to help establish and implement a bleaching monitoring programme.

Owen Day has sent a proposal to the Tobago House of Assembly (THA) for the monitoring programme called "Urgent Assistance for Monitoring of Coral Bleaching Event in Tobago", that BRT would coordinate. The THA have agreed to assist by providing some of the required funding for the immediate surveys, and a collaborative project is now being planned. But, "additional assistance will be required to fully assess the medium and long-term mortality associated with this bleaching event", Day said.

BRT's project aims to provide stakeholders with the "relevant information for the management and protection of Tobago's coral reefs". "In particular, the project will highlight the need to improve the management of Tobago's watersheds and coastal areas in order to reduce pollution and sedimentation - issues that are currently threatening the sustainability of the island's tourism industry," they say.

They want to find out the extent and severity of the bleaching; what the prospects are of medium and long-term recovery of the corals; and the effects of additional stresses of sedimentation and sewage pollution. BRT say it is essential to improve awareness "among all stakeholders of coral bleaching and other issues related to the conservation of Tobago's coral reefs".

As Day admitted, monitoring is all very well, but what really matters is action to reverse the human impacts. Deeds to defy the death sentence. The Caribbean bleaching event, he said, "is a dramatic reminder of the mantra of the environmental movement-'Think Globally and Act Locally'."

Ron, yes it is happening on Bonaire. We saw a LOT of it at some sights. I posted a pic of some in my trip report (Loo Hoo's). Ol' Blue was probably the site where I noticed it the most. It was very disheartening. Toward the end of the week it was apperant at every dive site...Susan Porter said the coral wouldn't "die" but it would take a long time for the reef to recover. When we arrived on bonaire on Oct 9th, and had dinner with her it hadn't started yet, she said it was going to be an interesting week to watch and see what happened...and it did.

Susan, if you're out there, any comments?

Ron, here is a picture I took last week.

Coral bleaching has been visible in Bonaire waters on all of my recent trips though it is localized, not widespread. Unfortunately while Bonaire's reefs are among the healthiest in the Caribbean, there has been a steady decline in hard coral cover. I remember reading a survey done of the reef in the research area north of Karpata a year or so ago showed a decline from about 65% hard coral cover on a prior survey to less than 40%.

A recent trip report posted on this site mentioned water temps of 89 F, and showed pictures of bleaching. Anyone who thinks global warming is a myth has not been diving in the tropics over the last ten years. It is frightening and depressing to think thar we may be the last generation to see these magnificent ecosystems, and to contemplate the consequences of their collapse.

I have always thought it odd that this topic seems taboo on this board. Not that it it is forbidden, just rarely mentioned let alone discussed. I have seen a marked decline in Bonaire's reefs over the seven years I've dived them. We are whistling in the dark in not discussing it.

David

David, I was there last week, when we arrived on the 9th the water was 89F. By the time we left it was registering 84-86F.

Cynde,

Was that 89 at depth?

David, it was 89F until you got to about 30 feet or so. A LOT of places with major thermoclines but they weren't "straight" thermoclines, you would hit it, but then at the same depth it would go away...really interesting! The water definitely cooled down though by the time we left, very noticeable difference than when we arrived. The last few days it was a consistent 86F at the surface and then around 84F or so at depth.

Thanks for the info...

It saddens me to hear that even healthy, protected reefs like those found around Bonaire can be damaged by a slight rise in temperature.

Too bad we can't just tow an iceberg over to cool things off!

Funny you should mention that...There was a story in the annual April fools issue of the Bonaire Reporter a couple of years ago reporting an iceberg being towed from antarctica to cool the waters of Bonaire.

Really?? :D

Yes, there really was such a story - I used to have an online subscription but it expired so I can't check the archives. Anyone who does can check the annual April Fools edition - it was at least 2, as much as 5 years ago. I think there was a report that some penguins hitched a ride on the 'berg.

-David

Here's a map of what's going on:

http://www.noaanews.noaa.gov/stories2005/s2526.htm

That maybe why the September Coral Spawning was so short, we only saw a few coral heads release eggs on Saturday 26th. We saw Touch me not sponges smoking and Brittle stars smoking and releasing eggs; but little hard coral spawning. Has anyone seen anything this month tonight should be the last night?

Brian, I remember you posting that there wasn't the spawining you had said you had seen before, and when I saw all the coral bleaching I thought the same thing, maybe that's why.

so what do we do about it?

Well Russ Europeans and most developed countries are trying to reduce CO2 emissions under the Kyoto agreement - as an example in the UK we have an additional 70% tax on fuels to encourage us to use less. This means we pay more than $10 a gallon for petrol. The government is about to strictly enforce the 70mph speed limit on our motorways to reduce emissions by a further 890,000 tonnes. I can see some sense in this, but it hurts financially when I filled up the car last week it cost £65.

Actually, the situation in Europe is a little more complicated then saying developed countries in Europe are supportive of Kyota because of their interest in the environment. I will suggest, that at least in Sweden, the government has raised taxes astronomically on petroleum products (gasoline)because they need the income to support their huge welfare programs. These programs insure that the Social Democrats maintain a power base amongst the 35% of the work force that doesn't work and the unions. Secondly , The Social Democrats maintain their power only with the help of the Green party which represents 5% of the voters. To prove my point they have received extra CO2 allowances from the EU so that they can import fossil fuel energy from other countries. This allowed them to close some of Sweden*s atomic energy plants, which the Green party insisted be closed.
I should also like to inflame many BT's by saying that while there is most probably a rise in global temperatures it is most unlikely that it is coming from human cause. And in fact even the rise in temperature can be debated. Please read this:
"Recently a team of scientists from NASA and the University of Alabama at Huntsville announced that global temperatures have been dropping, not rising, over the past two decades based on satellite data. But at the same time, the Global Climate Change Information Programme finds that temperatures have been warmer in the past 10 years than at any other period during the last 140 years! The Marshall Institute finds that temperatures have increased by approximately 0.5 C over the last century, but they contend that the change actually took place in the first half of the century—long before man was in any position to have a real impact on the atmosphere."
"The Earth's climate is governed by a myriad of complex factors including solar activity, plate tectonics, natural emissions from geological features such as volcanoes, ocean currents, geography, cloud cover and the effect of gases other than CO2 in the atmosphere. Over the last several millions of years the Earth's climate has continually changed—sometimes abruptly, with significant impact on fauna and flora—but we really do not know why. What we can say is that climate change has been a natural phenomena throughout the course of time. What impact do man's activities have on the Earth's natural climate cycles? That is still open to debate. Some would say none at all while others will say that it is dramatic.
Recently, one scientist, Robert Essenhigh, E.G. Bailey Professor of Energy Conservation at Ohio State, set the familiar arguments on their head by claiming that increasing CO2 levels in the atmosphere are a symptom, not the cause, of rising temperatures. “At six billion tons, humans are then responsible for a comparatively small amount—less than 5 percent—of atmospheric CO2,” he says. As temperatures rise, the CO2 equilibrium in water changes, releasing more CO2 into the atmosphere. "
Why is it that we never hear any opposition to the current view that man is causing global warming.. This too is political. A couple of 100 years ago all authorities claimed the earth was flat. You risked lynching to say otherwise. All the scientists who claimed the earth was flat were given prime "air time" on the media of those years. The others were contained (some killed). That is precisely what is happening today. Good scientists holding opposite viewpoints are not being heard. But these people do exist at our universities and other institutions. They just are not receiving government grants and they are not receiving prime "air time"
The environment is extremely complex and it is very difficult to really find the truth. I'm not yet convinced man is the cause even if I do believe we are in a warming period
If anyone is curious do google something like "global warming myth" and read.

Sigh. I wasn't going to respond to this, but Carter, it's sorta sad that you'd "like to enflame many BT's" regarding global warming.

Your post covers a lot of territory, all the way from the "huge welfare programs" of the Swedish government and its collusion with the Swedish Green Party, to "contained" scientists with opposing views to global warming swinging in the grantless, fundless flat earth breeze.

Most of the media I see covers "global warming is a myth" with as much depressing regularity as
"global warming is a fact". I believe the current US administration has repeatedly stated that global warming is "bad science" and "unprovable" in its opposition to the Kyoto Accord, so it's unclear to me how you can say that we never hear opposition to global warming as a fact.

I do agree that many things are political, though. When I googled "global warming myth" one of the first sites I got was a cut and paste of a Wall St. Journal article from Dec 4, 1997, "Science has spoken, Global warming a myth". Yes, I'd have to agree, the Wall St. Journal probably had a political motive to publish such an article in 1997.

Me, I'd prefer to cut my fossil fuel consumption if only to avoid giving generously to the Big Oil Retirement Fund.

Hi Fiona
Actually, I don't like enflaming my BT friends but I thought my words might. I think its healthy that both sides of the equation are explored and it appears you are aware of both views. This is good. It also says to me that you don't live in Europe and definitely not in Sweden. Here in Sweden it is a fact that man is the culprit. There is also an undertone in the media that its only Bush (and his capitalistic exploitations) that are endangering the world by not agreeing to the intentions of Kyota. I was unaware that in USA both sides of this problem are being debated

Hi Carter, actually I live in Canada, where in the very far north areas of the permafrost (permanently frozen ground) are melting, which has not happened since before the last Ice Age. It is certainly making it harder for the Inuit to follow traditional hunting patterns on the thinner or non-existant sea-ice. If whatever is causing this continues, I guess it will make diving in the Arctic Ocean more accessible.

Seriously, though, it has been reported that the Northwest Passage (through that jumble of islands north of the Canadian mainland) may actually become open water year round, rather than solidly frozen for 3/4 of the year. We'll have to give more $ to the Canadian Navy to patrol this Arctic shortcut.

The general tone here is that global warming is a fact, the environment is complex in its workings, we don't know but half of it, and that humans have some part in contributing to global warming. I have a feeling that this is right.

Eh, Carter, I just watched a Canadian TV show called Newsworld, which profiled a Canadian Inuit (old terminology - Eskimo,) community called Pangnirtuk - if you look on a map, this community is on the Arctic Circle---as far north as Boden, Sweden, or for my American friends, just north of Nome, Alaska---anyway, at this time of year, the sea ice is usually strong and deep enough to dive a car across...right now, there is just slush...the Innuit (Eskimo) have no words to describe this thaw...

Sorry, Carter, but if the people who have lived here for many thousands of years have no words for this, something is really wrong.

Thank you for explaining what Inuit means from your previous post.

This is all very interesting, even to a current Floridian.

Just to add to this: a coral bleaching event would typically last in an order of weeks. Following this period, the coral would either recover or die. Should the latter occur, the coral is usually then covered with colonising algae. On a brighter note, however, there is a chance that the symbiotic algae (known as Symbiodinium) may adapt to global warming. Indeed, I do know of one study that demonstrated some species of coral adapting to rising sea temps as a result of hosting specifically adapted Symbiodinium taxa!

That's interesting Sarah: thanks for the adaptation info. I was hoping that adaptation could occur. Do you happen to remember what species of coral?

Sarah, thanks! Are you still going to Bon in December? If so, you can let us know how it's recovering. In October, it was more apparent at certain dive sites than others. Susan Porter did say that she thought it would recover, as most of it was just slightly affecting the coral (slight lightening on the bulges), or portions. I didn't see any complete bleaching of an entire animal...(coral is a marine animal, right? Ms. Marine Biologist?)

Hi Cynde Loo Hoo!
Yes, coral polyps are animals (cnidarians). FYI, I am actually an Environmental Biologist covering land, sea and our atmosphere. Although I did study marine science for a while… (I switched)!Yes, we leave for Bonaire December 27th (can't wait)! I will post my comments on the bleaching in my Trip Report. The recovery of the corals on Bonaire will depend on other stressors too, such as UV radiation, pollution and nutrient load. It should also be noted, however, that coral recovery will vary among taxa

Hi Fiona,
In Kenya, some coral reefs are surviving temperatures of c.26 degrees celcius. Basically, the selective pressures of a changing climate could end up changing taxa >ing recovery rates. In addition, I belive it was Symbiodinium D? that was most resilient to the temp change. I will try and find this report again for you. I read it some two years ago! As for the species, possibly the hard corals.. again, I will try to find this report for you. Certainly, to me, it makes sense

I hope this make sense after a few beers?

Meaning I have just had a few! (Hick)

oh, ok, sarah...i've had a few too and didn't understand it too well. i'll read again sunday and see if it makes more sense then. my neighbor had given me a dvd to watch...called "what the bleep do we know". something about quantum physics. at the end it said something to the effect of "if you understood this movie, you don't....if you are totally confused, you got something out of it". i was in the "totally confused" group.

boy, glad i read the response before I had my martini! LOL! I understand it Sarah, I'll be interested to see how it looks when you are there, and hear your thoughts

Now, to my sipping and eating vodka soaked olives....mmmmmmmmm

Thanks for that info, Sarah. I'll look forward to your trip report also.

Mmmm indeed, Cynde, vodka soaked olives....

OK good, all is well then!