coral reefs doomed -- and the ABH and carbonate saturation

Richard Grigg rgrigg at soest.hawaii.edu
Tue Sep 18 16:37:27 EDT 2001


Dear Bob,

         Thank you for shedding some more light on your adaptive bleaching
hypothesis and as you point out, there is almost a complete absence of
hard evidence either for or against the argument.  In this regard, I don't
have to remind you, that absence of evidence is not evidence of absence
(of coral's adaptive abilities).  Also, in this regard, I think we can
infer more from the fossil record than most of us seem now willing to
accept even though the adaptive responses have the benefit of thousand or
even millions of years.  BUT, over the millenia, there must have been some
rapid bursts of sudden change such as the K-T event itself.  Stephen J.
Gould's view of evolution by punctuated equilibrium is, in fact, based on
such bursts of change.  And yet, we don't see much extinction in corals at
least at the generic or Family level (Re: Veron's work).  Doesn't this
imply high adaptive ability?  Perhaps we need to revisit the fossil record
more often and pull in the views of John Pandolfi and Charley Veron (where
are you guys?).

         Also, while I am at it, let me ask you to shed some of your
exceptional knowledge and experience in marine geo-chemistry on the
problem of decreasing carbonate saturation state in the world's oceans as
a result of increasing co2 globally.  I think there is an equally broad
pool of misunderstanding about the degree to which existing carbonate
sediments in the world's oceans, can serve as a buffer to this effect???  
I for one would appreciate hearing your insights on this question.  Hope
this question does not pose to great a burden but I'm sure the coral reef
community will appreciate your views.

 Rick Grigg
 Dept. of Oceanography
 University of Hawaii

At 12:58 AM 9/18/01 -0500, buddrw wrote:
>Coral-listers;
>
>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
>confusion.
>
>Bob Buddemeier
>
>PS:  I stand by my original statements.
>
> >===== Original Message From <oveh at uq.edu.au> =====
> >Dear Bob and others,
> >
> >I was triggered to respond by the inferences in your statement that some
>"reef
> >ecology and conservation" types have trouble with the Adaptive Bleaching
> >Hypothesis.  Any practicing experimental scientist would have an issue with
>the
> >state of play regarding support for this hypothesis. The basic problem at
>this
> >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
>for
> >the definitive data that shows corals will bleach, get rid of one
>dinoflagellate
> >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
>does
> >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
>another
> >(simply up-regulating one strain over another is not sufficient - that is
> >acclimation and is not surprising).  The experimental design was also
>confounded
> >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
>corals
> >died more at deeper site - which has nothing to do with the fact that they
>did
> >not bleach!).
> >
> >Other issues abound and concern us "reef ecology and conservation types" -
>the
> >idea of range of expansion is limited (as outlined by several people so 
> far)
>by
> >the fact that light may be a more important limiting than temperature.  I
>also
> >want to stress that the issue of the decline of reefs (as you, Bob, did
>state)
> >has nothing to do with the extinction of corals.  As the "geo types"
>(deliberate
> >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
>the
> >current human dependency on coral reef ecosystems - reefs disappearing for
>even
> >a few decades would present serious issues for several hundred million
>people.
> >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
>reef
> >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
>societies
> >to these changes.  This research direction, if the projections of the 
> future
>are
> >correct, will assume a major significance as we enter the next few decades.
> >
> >Best wishes,
> >
> >Ove
> >
> >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 uq.edu.au
> >http://www.marine.uq.edu.au/CMS_pro/www/staff.html
> >
> >
> >-----Original Message-----
> >From: owner-coral-list at coral.aoml.noaa.gov
> >[mailto:owner-coral-list at coral.aoml.noaa.gov]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
>disturbing
> >article.
> >
> >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
>as
> >you move to higher latitudes (no atolls, narrower shelves, etc.)
> >2.  Light -- see the Kleypas et al analysis -- Kleypas, J.A., McManus, J.W.
>and
> >Menez, L.A.B., 1999. Environmental limits to coral reef development: 
> Where do
>we
> >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
>variations
> >-- which aren't going to change.
> >3.  Carbonate saturation state decrease is squeezing from the high latitude
> >sides -- see the US National Assessment,
> >http://www.cop.noaa.gov/pubs/coastalclimate.PDF, 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
>et
> >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
>in
> >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
>seriousness
> >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,
>by
> >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
> >> (http://coral.aoml.noaa.gov/bulls/ITMEMS-bleach.html) 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
>bleaching.
> >>
> >> Microscopic algae that support the coral polyps cannot live in the warmer
> >> water, and the polyps, the tiny creatures who actually create the reefs,
>die
> >> off within weeks.
> >>
> >> Scientists agree the world's oceans are now warming at a rate of between
>one
> >> 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
>and
> >> 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
>wrath
> >> 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 www.coral.noaa.gov, 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 kgs.ukans.edu
> >
> >
> >~~~~~~~
> >For directions on subscribing and unsubscribing to coral-list or the
> >digests, please visit www.coral.noaa.gov, 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
>USA
>ph (785) 864-2112; fax (785) 864-5317
>email: buddrw at kgs.ukans.edu
>
>~~~~~~~
>For directions on subscribing and unsubscribing to coral-list or the
>digests, please visit www.coral.noaa.gov, click on Popular on the
>menu bar, then click on Coral-List Listserver.


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



More information about the Coral-list-old mailing list