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wwguy
01-24-2012, 05:51 PM
For those concerned about the recent decline in the health of Bonaire's reefs, and for those who may be reluctant to concede that a negative change is occurring; I think you will find this report to be both informative and insightful.

A new 137 page report titled Status and Trends of Bonaire’s Reefs: Cause for Grave Concerns (http://www.bmp.org/pdfs/Bonaire_Report_2011_FINAL.pdf) was recently published in PDF format by the Bonaire National Marine Park (BNMP) on this webpage (http://www.bmp.org/publications.html). Based on the title of the report, this would also seem to be the basis for the lecture with the same title scheduled to be given by Ramon de Leon, BNMP Manager, at the CIEE Research Station on Bonaire tomorrow night. If anyone reading this post attended that lecture, I'd appreciate reading a summary or your observations on the lecture and any resulting audience Q&A.

The entire document is only 6MB, so downloading shouldn't be a problem. At a minimum I recommend reading the 7 page Executive Summary on pages 7 to 13.

Paraphrased highlights from the Executive Summary section include:

Unusually warm ocean temperatures surrounding Bonaire during the late summer and fall of 2010 caused 10 to 20 % of corals to bleach.
Bleaching persisted long enough to kill about 10 % of the corals within six months of the event.
This increase in non-coral substrate (i.e. dead coral) increased the area algae can colonize, and the area parrotfish must keep cropped short.
Thus, herbivorous fish (parrotfish and sea urchin) biomass and population densities would have to increase for there to be no incremental change in seaweed (algae) abundance, but they have been steadily declining in recent years.
A decline in parrotfish and sea urchin numbers continues despite the establishment of no-take areas, called Fish Protection Areas (FPAs) and the recent law that completely bans the harvesting of parrotfish.
Damselfishes continue to increase in abundance (except in FPAs) and their aggressive territoriality reduces parrotfish algae-eating activity where they are present.
The declines in herbivory algae eaters resulted in a marked increase in macroalgae.
All research to date indicates that coral health and recruitment declines directly with increases in algal abundance.

To put it a simply as possible: Warm water killed 10% of the coral, which resulted in 10% more surface for the "bad" kind of algae to grow. In a balanced ecosystem bad algae would normally be eaten by parrotfish and urchins. But parrotfish and sea urchin numbers are steadily declining for other reasons, rather than increasing, which further propagates the growth of more bad algae. Further complicating matters, Coralline algae, the "good" algae which has been shown to facilitate coral recruitment, remains at or near unprecedentedly low levels. More bad algae and less good algae results in declining coral health and inhibited coral reproduction... and so the cycle continues in a downward spiral.

Thus the report's Executive Summary conclusion:
"Overall, Bonaire’s coral reefs today are more seriously threatened with collapse than at any time since monitoring began in 1999."

There is a little bit of good new in this report however: Predatory fishes including snappers, groupers, barracuda, grunts and others increased in abundance at the monitored sites. Unfortunately, specific predators known to eat damselfishes showed variable population densities with only a hint of an increase in 2011.

The final paragraph of the executive summary contains this ominous warning:
"The trend of greatest concern is the steady decline in parrotfish abundance despite very recent laws banning their harvest. It is possible that the timing of the bleaching event may have increased the area for algal colonization such that existing herbivores were overwhelmed by rapid algal growth which may negatively affect subsequent herbivory (see discussion in McMahan Chapter 4). If so, this would suggest Bonaire’s coral reefs could be slipping into a feedback loop that could continue and drive the reef towards a coral depleted state (Mumby and Steneck 2008)."

I confess that I haven't read the report in it's entirety yet, but I will soon. The information above is skimmed and/or paraphrased from the Executive Summary section.

I'm very much interested in what you all think about this report, and about what you think we can do to slow, stop, or reverse this downward trend in the health of our beloved reefs. After I've spent some time pondering, I plan to return to this thread to post some examples of what we may be able to do, both individually and collectively, to mitigate or reduce our negative impact on Bonaire's delicate ecosystem.

Ten years ago I brought my teenage son to Bonaire for his first Caribbean dive trip. Next month I'll welcome my first grandson into the world and I'd like to dive with him on Bonaire someday too. I can't help but wonder what Bonaire's reefs, and the other reefs in the world, will be like in another 15 years. Right now the future doesn't seem to be looking very bright.

For now... Happy Diving.

-Roger

coldwaterlloyd
01-24-2012, 06:43 PM
Thanks for posting Roger . It is the smoking gun that reefs are endangerd and instant action should be taken to try to at least stop the pollution , which is like throwing gas on fire .

DiverVince
01-24-2012, 06:50 PM
Roger..Thanks much for posting this. The more heightened awareness we have, I think the better the local government can pass the appropriate laws to protect the reef. I'm sorry I'm not on island to attend Ramon's lecture tomorrow evening! I do remember the waters were EXTREMELY warm the summer 2010.

grunt
01-24-2012, 10:55 PM
Will an island wide functioning sewer system, should that ever become a reality, help in limiting algea growth?

randl
01-25-2012, 12:00 AM
Will an island wide functioning sewer system, should that ever become a reality, help in limiting algea growth?I'm still making my way through the report but it does seem to play down the role of nutrients in the problem. For example, it reads, "Most studies have shown that herbivory from scraping herbivores such as parrotfishes and sea urchins controls algal abundance much more strongly than nutrient availablity (McCook 1999, Williams and Polunin 2001, Kramer 2003, and Mumby and Steneck 2008). Other studies have indicated that herbivores facilitate coralline algal abundance (van den Hoek 1969, Steneck 1986, 1988, 1997, Steneck and Dethier 1994, Edmunds and Carpenter 2001)."

On the other hand, it adds, "...other local measures can be taken to mitigate stress on reefs, including improving land use practices such as restricting coastal development and reducing nutrient input."

On balance, the report places the cause of the decline of corals on higher ocean temperatures along with a reduction in herbivore activity to control the algae. Of course anything that controls algae in addition to parrotfish would be helpful.

tursiops
01-25-2012, 11:36 AM
The euphemisms are remarkable. "...reduction in herbivore activity..." Let's just call it overfishing by the locals, to whom the rules do not apply, or against whom the rules are not enforced. It has been going on forever, but has reached its tipping point. Who among us has not seen that fishing taking place?

smits
01-25-2012, 12:28 PM
Lets just NOT call it overfishing by the locals.
The real overfishing is done by the "developed" world, using factory ships.

This is what Stinapa says:

Fishing
Bonaire is popular for fishing. We recommend targeting blue water fish and leaving our reef fish on the reefs. Trolling along our protected west coast often attracts tuna, wahoo, barracuda or mahi mahi. The best places to bone fish are Lagun or the Sorobon side of Lac, in the area called ‘Aw’i Meuchi”. Bone fishing or any type of fishing activity is not allowed in the salt flats. Fishing can only be done with line and hook. We recommend practicing catch and release at all times. Taking sea turtles or conch, or using a spear gun or hand spear is prohibited by law.

The local fisherman you see fishing on our reefs have been doing so for generations. To many it is their only source of income. Please do not cut their fishing lines!

tursiops
01-25-2012, 05:12 PM
Come on Smits; are you really saying that the Bonairian parrotfish are gone because of factory ships in the developed world?

Nothing in the Stinapa statement mention over fishing or sustainability. What it says is the locals have been fishing the reefs for generations. That is exactly my point: the locals are the only people fishing the reefs, the parrotfish are gone. The locals passed the tipping point without any thought as to sustainability....just doing what they've always done. Too much, for too long.

coldwaterlloyd
01-25-2012, 05:20 PM
Combination of pollution , over fishing , a chain reaction starts . We are witnessing the end of coral reefs as we know them . It was predicted twenty years ago .

smits
01-25-2012, 05:25 PM
@tursiops
No, that is not what I wanted to make clear.

Saying that the locals are overfishing is in my opinion much too strong a statement. They are fishing for generations. very often with line and hook. Sometimes with nets.

The real overfishing in the oceans is done by the factory ships of the "developed" nations.

Probably "us tourists" do more harm to the ecoligcal system.
We fly to Bonaire, use the stressed sewage system, drive our cars over the island, or arrive with cruise ships.

And that on an island that, not so very long ago, used to have 9.000 inhabitants. With all the financial restrictions.

And I'll admit. I'm part of that problem too,
I vist Bonaire since 1977. The situation of the reef and the fish population is incomparable to that time.
And that is not because locals are overfishing.

tursiops
01-25-2012, 05:33 PM
smits, I agree completely that we are part of the problem, in a general, global sense, and that overpopulation is the source of many of our ecological difficulties. But that is not wht this thread is about.

My "locals overfishing" comments are related only to the decline of the local parrotfish. They have been fishing them for generations, but that does not mean they should! If the parrot fish are in decline, and if that is a serious problem for Bonaire's reefs (the point of this thread, after all), then the fishing needs to stop, and to be enforced. On Bonaire, this might mean some other ways to ensure subsistence for the locals......but if they keep taking parrotfish, then their children will not be able to fish....it is a death spiral for the reefs that is not unique to Bonaire.

CaptNick
01-25-2012, 05:54 PM
When we were on the Island last April, it was the Easter weekend and I believe it is when locals can camp anywhere they want. My most fav dive site was turned into ruins with the shacks they put up. Local families who were living there were constantly catching reef fish. I have seen huge parrotfish being hacked into pieces. When I tried to get the camera and take pictures I was intimidated with a nice shiny blade. And fried in pans all day. Moving to present day, this December which is only 6+ mnths later, I saw no big parrot fishes or even the huge angel fishes we admired previous 2 trips.. very sad... I am already reading chatter in other forums that some people are changing destinations due to state of reef and marine life.

wwguy
01-25-2012, 10:33 PM
I am already reading chatter in other forums that some people are changing destinations due to state of reef and marine life.

The collective and individual perceptions of situation perplex me, as do some of the responses. Similar to CaptNick's observation, last month I met experienced divers on Bonaire who, after 2 weeks of diving sites north and south, were disappointed and felt that the reefs were almost completely dead! (Equally unfortunate was that they intend to go elsewhere next year, rather than expend time or energy towards understanding or improving the problem.) On the other end of the spectrum are optimistic and/or new divers who report that the Bonaire's reefs are in great shape, despite sharing photos and videos evidence to the contrary. Personally I believe the truth is somewhere in between, as detailed in the recent BNMP report. There is still much beauty to be found on Bonaire's reefs, but they are in distress.

The tourism industry is not helping matters. Dive travel magazines, which are dependent on advertising dollars, continue to post rave reviews, beautiful photos, and rankings based on subscriber "votes". The resorts advertise in the magazines, build web pages and blog, leverage Facebook, and otherwise work hard to create a positive public perception in order to attract divers to their businesses. The cruise ship industry follows similar practices. And the Bonaire Tourism Corporation creates a similar "positive presence" to support all of the above, plus anything else having to do with generating tourism revenue on Bonaire. This is all part of the Tourism Machine.

The unfortunate downside is that all of these businesses and supporting organizations measure success via revenue and business growth calculated today. They're reluctant to acknowledge, much less communicate to potential clients, that there may be trouble in paradise. I'd like to believe that it's not that they don't care about Bonaire's delicate ecosystem. Most of them live on Bonaire, and I prefer to believe that they do care very much. Either way the reality seems to be that their short-term business goals result in actions that are equivalent to sweeping the proverbial dirt under the carpet.

To be sure, global warming and rising sea temperatures won't be affected by behavioral changes at a local level on tiny Bonaire. The best they can hope for is enough small changes in human behavior to address peripheral influencing factors. Examples include efficient wastewater collection and treatment, shipping garbage off-island, enforcing fishing regulations on the reefs, and continued lionfish depredation efforts by authorized divers. I'm sure there's probably more. But measurable improvement in reef health isn't likely to occur in the near-term if the diving community, tourism industry, and government won't admit there is a real problem that requires action tomorrow. Similarly, everyone affected has to admit that tough times require tough measures, and that these measures are going to cost money. Somebody has to pay sooner or later. The Pied-Piper is in Bonaire today. His name is Tourism.

If willing, members of the BT community can help today by redirecting some of the hours spent posting webcam pics, playing games, and reviewing restaurants towards pondering this problem. I encourage you to educate yourselves, consider your personal actions, and spread the message that Bonaire needs help soon. (I think they call this "spreading awareness".)

-Roger

P.S. - If anyone on Bonaire attended Ramon de Leon's lecture at CIEE tonight, I'd love to hear how it was received!

randl
01-26-2012, 12:01 AM
Apparently the idea that algae accumulation due to reductions in parrotfish abundance (due to over fishing) is not shared by all. Check this link and the lively discussion that follows at the bottom of the page... http://tech.groups.yahoo.com/group/coralreef-freeforall/message/231. Their message is that warming ocean temperatures and nutrients are the real culprit.

tursiops
01-26-2012, 11:10 AM
People seem to try awfully hard to find "the" culprit, the single thing that went wrong, the one thing to fix.
That's not how it works. It's a whole bunch of stuff, all in balance, and usually several things have to go wrong before things go sour. Everything everybody has mentioned is a problem: global warming, too many nutrients (a nice word for fertilizer plus you know what), loss of critical species of fish, coral diseases, invasive predators (yes, the lionfish), divers, boat anchors, the list goes on and on.

The ecological system is surprisingly resilient. Changing an element in the balance of effects might shift the balance a little.....too much warming and the exact species of animals and algae shift, but the system rarely dies. Change everything however, and it is harder -- or impossible -- for the ecosystem to sustain itself. Adaptation to change works, but only such much change can be adapted to in a short time.

There are pretty well-understood indicators of danger (that each might have several reasons to occur): extended bleaching, algae growth, disappearance of certain species and appearance of others, for example. The Stinapa report focused on some of the danger signs, in particular those that were not locally driven...like global warming. Bonaire is not the source of global warming, so that is a safe danger to talk about. Others -- nutrients and local over fishing -- are either downplayed or mentioned only in euphemisms. The article was pretty clear that declining parrotfish populations is a problem. Very likely it would NOT be a problem were it not for the extra algae, driven by the bleaching, fueled by the nutrients, etc.

In the end, Bonaire can only control what it can control, adapt to what it can adapt to, and hope it all stays in balance in such a way that local subsistence fishing can continue, divers keep coming, and the sun keeps shining. But hope is not a strategy, and the danger signs have to be taken seriously. All of them. You do not know which straw is the last one......

Scuba Sheila
01-27-2012, 10:07 PM
If only there were a magic wand.... :( Though I agree hope is not a strategy, I will still continue to hope for some real positive changes to some real negative problems, and will hope that somehow, someway Bonaire's reef system will thrive once again. And hope that we can, in some way, help to make this possible! :)

Azureblue
09-17-2012, 03:37 PM
I don't give a damn about the restaurants, or webcams that's for sure. I did enjoy Captain Nick's post very much. I've been all over this website and have found different environmental grass roots movements happening, sea turtle conservation, the coral nurseries etc.., but for an island dependent economically on the reef and tourism, and supposedly on the environmental forefront, it is odd that there doesn't seem to be a center, a single organization or person who heads up the many who have these concerns. We have a second home in Kralendijk, but don't live there most of the year. I would like to write some letters regarding the Maryland Study and other, earlier studies.. Also, has anyone thought of a Parrotfish nursery?? WHERE to I write letters to people in government? Since the mail takes 8-10 weeks from the U.S., is there a person who receives emails on behalf of the powers that be? Preaching to the choir will only get you so far.... I would like to take more concrete action.

Narced One
11-07-2012, 02:25 PM
R.I.P. Angel City. Visited Week of Oct. 20th

Bob T
11-07-2012, 05:06 PM
Good Wednesday afternoon everybody. I was just on the Bonaire Reporter and they have a piece on page 4 about what might happen to our beautiful Bonaire if the Dutch Govt has their way. It's an interesting article on over tourism and over development that is a little like when Aruba changed.