coral reefs doomed -- and the ABH

buddrw buddrw at
Tue Sep 18 01:58:14 EDT 2001


I have received, in addition to this broadcast message from Ove, other
personal communications that indicate that there is a fairly broad pool of
misunderstanding about what the Adaptive Bleaching Hypothesis is and
isn't.  The comments below address primarily things that it isn't, and I
have sent messages to Ove and others on an individual basis to try to get
this sorted out so that a productive discussion can ensue.

In the meantime, I heartily recommend recourse to the original literature
as a source of primary information -- I, Daphne Fautin, and John Ware will
all be more than happy to answer questions or attempt to clear up

Bob Buddemeier

PS:  I stand by my original statements.

>===== Original Message From <oveh at> =====
>Dear Bob and others,
>I was triggered to respond by the inferences in your statement that some 
>ecology and conservation" types have trouble with the Adaptive Bleaching
>Hypothesis.  Any practicing experimental scientist would have an issue with 
>state of play regarding support for this hypothesis. The basic problem at 
>point is nothing to do with "culture" - it is more to do with hard evidence,
>which is almost completely lacking to support this still very soft and
>hypothetical explanation for why coral bleach.  While experimental tests have
>been coming in, they have had serious problems in terms of design and the
>conclusions they draw. Us "reef ecology and conservation types" still wait 
>the definitive data that shows corals will bleach, get rid of one 
>genotype and adopt another WHILE the thermal (or other) stress is still being
>applied to the coral-dinoflagellate association.  This has never been shown.
>Showing diversity in rDNA is interesting but irrelevant if diversity here 
>not relate to relevant physiological differences.  The recent paper by Baker
>(whom I greatly respect), for example, used light and could not prove (using
>RFLPs) that his corals had changed from one dinoflagellate genotype to 
>(simply up-regulating one strain over another is not sufficient - that is
>acclimation and is not surprising).  The experimental design was also 
>by the fact that stressed corals were placed in the two contrasting and
>confounding (for the experiment) habitats (one, the deeper site, was at the
>extreme depth limit of the species concerned while the other was clearly more
>optimal after photo acclimation). It is therefore not surprising that the 
>died more at deeper site - which has nothing to do with the fact that they 
>not bleach!).
>Other issues abound and concern us "reef ecology and conservation types" - 
>idea of range of expansion is limited (as outlined by several people so far) 
>the fact that light may be a more important limiting than temperature.  I 
>want to stress that the issue of the decline of reefs (as you, Bob, did 
>has nothing to do with the extinction of corals.  As the "geo types" 
>use here) tell us worse things have happened to corals and they have bounced
>back (but over thousands if not millions of years).  The issue, however, is 
>current human dependency on coral reef ecosystems - reefs disappearing for 
>a few decades would present serious issues for several hundred million 
>The idea of finding out how reefs survived major extinction events is
>interesting but largely irrelevant to the current discussion.
>So - out I come on my old hobby horse - we still have no evidence of unusual
>adaptive abilities of corals that will match the fast rate of change.  Us 
>ecology types keep looking. While looking for this evidence - perhaps we also
>need to focus on how reefs will change and how we can "adapt" as human 
>to these changes.  This research direction, if the projections of the future 
>correct, will assume a major significance as we enter the next few decades.
>Best wishes,
>Professor Ove Hoegh-Guldberg
>Director, Centre for Marine Studies
>University of Queensland
>St Lucia, 4072, QLD
>Phone:  +61 07 3365 4333
>Fax:       +61 07 3365 4755
>Email:    oveh at
>-----Original Message-----
>From: owner-coral-list at
>[mailto:owner-coral-list at]On Behalf Of Bob Buddemeier
>Sent: Saturday, 8 September 2001 4:00 AM
>To: Jim Hendee
>Cc: Coral-List
>Subject: Re: coral reefs doomed?
>Jim, et al.,
>Good questions, good points, -- and like it or not, a pretty good if 
>On your question about range expansion to compensate for temperature increase
>and inhospitably hot tropics -- there are unfortunately 3 geographic factors
>that work against that.
>1.  The available shallow water benthic area decreases rather significantly 
>you move to higher latitudes (no atolls, narrower shelves, etc.)
>2.  Light -- see the Kleypas et al analysis -- Kleypas, J.A., McManus, J.W. 
>Menez, L.A.B., 1999. Environmental limits to coral reef development: Where do 
>draw the line? American Zoologist, 39(1): 146-159.  Maximum reef depth shoals
>dramatically at higher latitudes, even within the thermal mixed layer.  This
>presumably reflects light limitations due to sunangle and day lenght 
>-- which aren't going to change.
>3.  Carbonate saturation state decrease is squeezing from the high latitude
>sides -- see the US National Assessment,
>, section 4.4.
>So there is little basis for optimism there.
>With acknowledgment of the terminological problems, some form of
>adaptation/acclimatization probably does have real potential to ensure the
>survival of corals , but not necessarily "reefs as we know them."   The Ware 
>al article and its precursor, Buddemeier, R.W. and Fautin, D.G., 1993. Coral
>Bleaching as an Adaptive Mechanism: A Testable Hypothesis. BioScience, 43:
>320-326, are looking more solid as experimental tests come in (Kinzie et al 
>Biol. Bull. earlier this year, Baker in Nature more recently), but for some
>reason this concept has been anathema to some reef cology and conservation
>types.  (see also Buddemeier, R.W., Fautin, D.G. and Ware, J.R., 1997.
>Acclimation, Adaptation, and Algal Symbiosis in Reef-Building Scleractinian
>Corals. In: J.C. den Hartog (Editor), Proceedings of the 6th International
>Conference on Coelenterate Biology (16-21 July 1995, Noordwijkerhout, The
>Netherlands). National Museum of Natural History, Leiden, pp. 71-76 for a
>related issue).  This may be because it is seen as diminishing the 
>of the bleaching problem, but in my view your position is the more valid --
>without some mechanistic reason to believe that corals CAN survive, there is
>very little justification for investing money in research and conservation.
>This also relates to my tired old hobby horse of the non-reef coral habitats 
>I don't think we are getting the real picture, or doing ourselves any favors, 
>exclusive concentration on reefs; corals have survived many periods of
>non-reef-building, and we had better figure out how, why and where.
>Thanks for bringing this up.
>Bob Buddemeier
>Jim Hendee wrote:
>> Dear Coral Colleagues,
>> I know I'll get raked over the coals on this (especially because I don't
>> have all the literature at my fingertips), but the content and tone of the
>> news article below is troublesome to me, even though such a tone helps to
>> gain attention, as well as funding, so that we can more thoroughly study
>> the problem of coral bleacing and global warming.  Of course I respect our
>> colleague's right to a viewpoint, but when I see this, I can't help but
>> have these thoughts:
>> Such a projection gives no "credit" to adapatation and natural selection,
>> even though such adaptation would have to occur under a relatively short
>> time span (50 years).  I believe Ware et al (1996), among others, have
>> addressed this.
>> As Dr. Al Strong and I have discussed, and as alluded to but unfortunately
>> not expanded upon in the last sentence of the article, if the seas are
>> warming, then you might expect the zoogeography of corals to expand
>> (relocate?) into the cooler areas, as long as the substrate, circulation,
>> light and water quality regimes are conducive.  (I would imagine some
>> coral researchers have modeled these possibilities, and I apologize for
>> not referencing your work.)
>> Even though high sea temperatures are the primary cause and indicator of
>> coral bleaching, that is not the only cause, and no credit is given to the
>> evidence in the literature (e.g., Lesser 1996, among others) that high UV
>> is also an agent in coral bleaching.  Higher UV, especially in the
>> tropics, is part of the problem as it relates to the earth's ozone layer.
>> There is evidence that high sea temperatures that elicited coral bleaching
>> at some localities in the past did not elicit coral bleaching during
>> extended cloudy periods (Mumby et al, in press). (Perhaps the cooler areas
>> mentioned in the above paragraph might also have lower UV?)
>> There are other causes of coral bleaching (e.g., see Glynn 1993, 1996) and
>> this manifestation of stress is complex and to my mind public statements
>> on coral bleaching should emphasize this.
>> Would an annual update to the ITMEMS statement on coral bleaching
>> ( be helpful for the
>> public in this regard?  It is my opinion that it would, that we should
>> address the topics above (among others, e.g., coastal effects), and that
>> it would behoove us to widely circulate the update among the press as a
>> consensus opinion (if that is possible!).
>> Just my two cents worth...
>>         Cheers,
>>         Jim Hendee
>>         NOAA/AOML
>>         Miami, FL
>> Glynn, P. (1993). Coral reef bleaching: ecological perspectives. Coral
>> Reefs 12, 1-17.
>> Glynn, P. (1996). Coral reef bleaching: facts, hypotheses and
>> implications. Global Change Biology 2, 495-509.
>> Lesser, M.P. (1996).  Elevated temperatures and ultraviolet radiation
>> cause oxidative stress and inhibit photosynthesis in symbiotic
>> dinoflagellates.  Limnol Oceanogr. 41(2): 271-283.
>> Mumby, P.J., Chisholm, J.R.M., Edwards, A.J., Andrefouet, S. & Jaubert, J.
>> 2001. Cloudy weather may have saved Society Island reef corals during the
>> 1998 ENSO event.  Mar Ecol Prog Ser (in press).
>> Ware, J.R., Fautin, D.G., & Buddemeier, R.W. (1996). Patterns of coral
>> bleaching: modeling the adaptive bleaching hypothesis. Ecological
>> Modelling 84, 199-214.
>> -------- Original Message --------
>> World coral reefs to die by 2050, scientist warns
>> By Ed Cropley, Reuters
>> Thursday, September 06, 2001
>> GLASGOW, Scotland — The world's coral reefs will be dead within 50 years
>> because of global warming, and there is nothing we can do to save them, a
>> scientist warned Wednesday.
>> "It is hard to avoid the conclusion that most coral in most areas will be
>> lost," Rupert Ormond, a marine biologist from Glasgow University, told a
>> science conference. "We are looking at a loss which is equivalent to the
>> tropical rain forests."
>> Only the coral reefs in nontropical regions such as Egypt stand any chance
>> of lasting beyond 2050, Ormond said, but even the days of the stunning
>> marine parks of the Red Sea are numbered as sea temperatures continue to
>> creep up.
>> In the past, reefs have suffered from sediment buildup and the coral-eating
>> crown-of-thorns starfish, whose numbers have exploded due to the
>> over-fishing of their predators.
>> Now the main threat to the delicate structures that harbor some of nature's
>> most stunning creations comes from warmer seas, which cause coral 
>> Microscopic algae that support the coral polyps cannot live in the warmer
>> water, and the polyps, the tiny creatures who actually create the reefs, 
>> off within weeks.
>> Scientists agree the world's oceans are now warming at a rate of between 
>> and two degrees Celsius every 100 years due to the increased amounts of
>> greenhouse gases in the atmosphere which trap the sun's rays.
>> But even if humans stopped pumping out greenhouse gases such as carbon
>> dioxide tomorrow in a bid to halt the process, it would still be too
>> late to
>> save the reefs, Ormond said. "I don't know what can be done, given that
>> there's a 50-year time lag between trying to limit carbon dioxide levels 
>> any effect on ocean temperature," he told the conference, held by the
>> British Association for the Advancement of Science.
>> The implications stretch far beyond the death of the colorful coral
>> structures themselves. The weird and wonderful eels and fish which inhabit
>> the nooks and crannies will become homeless, and many species will die out.
>> "We are looking at a gradual running down of the whole system. Over time,
>> the diversity of coral fish will die," Ormond said.
>> Humankind will also suffer directly as the dead reefs are eroded and
>> shorelines that have been protected for the last 10,000 years face the 
>> of the oceans without their natural defenses.
>> In an age of relatively cheap scuba-diving holidays, this also means many
>> developing countries in the tropics, such as Kenya or those in the
>> Caribbean, face losing a major source of revenue.
>> The only cause for optimism was that new coral reefs could start to emerge
>> in colder waters such as the north Atlantic Ocean and Mediterranean Sea.
>> Copyright 2001 — Reuters
>> ~~~~~~~
>> For directions on subscribing and unsubscribing to coral-list or the
>> digests, please visit, click on Popular on the
>> menu bar, then click on Coral-List Listserver.
>Dr. Robert W. Buddemeier
>Kansas Geological Survey
>University of Kansas
>1930 Constant Avenue
>Lawrence, KS 66047 USA
>Ph (1) (785) 864-2112
>Fax (1) (785) 864-5317
>e-mail:  buddrw at
>For directions on subscribing and unsubscribing to coral-list or the
>digests, please visit, click on Popular on the
>menu bar, then click on Coral-List Listserver.

Dr. Robert W. Buddemeier
Senior Scientist, Geohydrology
Kansas Geological Survey
University of Kansas
1930 Constant Avenue
Lawrence, KS 66047
ph (785) 864-2112; fax (785) 864-5317
email: buddrw at

For directions on subscribing and unsubscribing to coral-list or the
digests, please visit, click on Popular on the
menu bar, then click on Coral-List Listserver.

More information about the Coral-list-old mailing list