Beyond bioerosion - the last word?

John McManus jmcmanus at
Tue Oct 9 12:07:19 EDT 2001

On the positive side, there are points at which this discussion has been
at the highest levels of scientific discourse, and many of us are grateful
for the opportunity to see the important points defended through citation
and example. Please keep smiling and keep going!



John W. McManus, PhD
Director, National Center for Caribbean Coral Reef Research (NCORE)
Rosenstiel School of Marine and Atmospheric Sciences (RSMAS)
University of Miami, 4600 Rickenbacker Causeway
Miami, Florida 33149.
jmcmanus at
Tel. (305) 361-4814
Fax (305) 361-4600

-----Original Message-----
From: owner-coral-list at
[mailto:owner-coral-list at]On Behalf Of Alan E Strong
Sent: Friday, October 05, 2001 9:45 AM
To: Mike Risk; Clive Wilkinson
Cc: Joanie Kleypas; coral-list at
Subject: Re: Beyond bioerosion - the last word?


Why isn't anyone talking about how much coral we have ADDED since the 1998
bleaching event!  At least I assume that what I hear from places like Fiji,
USVI, Bahamas, Palau, correct...?  Clive, would you concur?

You stated: "The difference between a discussion and an argument is: in an
argument, no one has any intention of changing their mind. This is an
one that has gone on for over a month." (your words) your own
definition it
would appear that there can be no "substantive response."!

If you intended this as an "argument" all along why was it posted and


Mike Risk wrote:

> I feel there is more that needs to be said on this, and other, issues.
> will, however, be my last submission on this particular topic.
> Given the involvement of CO2, I am moved to consider the analogy of
> scientific papers as automobiles. I view most of my papers as I view my
> 12-year-old Subaru, that sits mutely rusting outside: inconspicuous,
> ignored, battered and beaten-but dependable transportation nonetheless.
> Should someone volunteer to put some Bondo on it to fill in some of the
> holes-well, be my guest. (You have Bondo? We need it up here.)
> The responses of Kleypas and co-authors to my comments on Kleypas et al
> (hereafter KEA, not to be confused with KIE) put me in mind of someone
> waxing a brand-new BMW: putting further polish on that which is already
> perfection. Woe betide those who would point out dents in a fender, or
> in a windshield...I had hoped for a response something along the lines of:
> "OK, we know there were some holes in the first version. We invite you all
> to help us do better next time."-but that isn't going to happen here. The
> difference between a discussion and an argument is: in an argument, no one
> has any intention of changing their mind. This is an argument, one that
> gone on for over a month.
> In that month, I estimate (using totally questionable assumptions!) that
> Asia will have lost 2-3 coral species, and that coral cover on some of the
> Florida Keys will have dropped another 2%. Reefs are in the midst of a
> extinction event right now, and pH hasn't budged. (Yes, I know about the
> open-ocean estimates-irrelevant, as you point out.) In the time I have
> crafting these responses, I could have written a formal rebuttal of KEA,
> that is what I will now set out to do.
> I also sense that the tone of the exchanges is becoming harsher, which is
> upsetting. I realise I am to a large extent at fault, here, being a direct
> and rude type. Those who know me may feel I have been well- behaved,
> those who don't may wonder why Jim Hendee let this raving maniac on in the
> first place. So. After this one, I will give up. I have concluded that
> will be no substantive response to any of my comments.
> I remain, as always, available for comments and exchanges, and would be
> delighted to give of advice or information in any of the areas in which I
> have some competence, as soon as I figure out what those areas may be.
> To begin with: KEA have made their predictions, based on models they have
> described in print and on the list. I am a field man (Omega, to me, always
> meant expensive wristwatches), so I tend to look at field evidence. Just
> about every reef worker (including Gattuso and Buddemeier) reports
> of carbonate at night, when CO2 is elevated-and Halley's work shows that
> this is solution of HMC. Additionally, KEA predict that corals should show
> 6-11% decline in calcification since about 1880. Lough and Barnes (2000)
> show an INCREASE in calcification of 4%, an increase that closely matched
> the prediction of increased calcification from elevated SST's. So at least
> one of their predictions is wrong already.
> When I first saw KEA, I predicted that it would be used by managers to
> divert resources away from local problems. This has already happened. In
> addition, my doomsday scenario (Twenty and Out) is still running well, and
> will finish no worse than .500.
> My rude comments about modellers (which really weren't mine, as I point
> out-although I ascribe to them) were met by Dr. Kleypas with the following
> series of responses (paraphrasing):
>     -KEA really only used the HAMMOC model to illustrate the long
> to buffering (although the model doesn't react quickly)
>     -there are models out there now that CAN react quickly (but we haven't
> used them)
>     -and besides, there are all these famous oceanographers out there who
> agree with us.
> What can I possibly do, faced with this response, but retreat licking my
> wounds? Seriously now, this is not convincing.
> Dr. Kleypas attempts to bolster her defense of the ocean models by
> denigrating/downplaying the importance of Smith et al, Nature 1997 (that's
> OK, so do the modellers). While she claims "corals from a single
> not provide adequate evidence" , that same finding was
> trumpeted, by one of her own quoted oceanographers, as "The New Archive
> we've all been waiting for." Would you have asked Newton to wait for MORE
> apples??? Sure, it's only one location-but it's the most precisely
> constrained major climatic event ever to be described from the ocean
> The results won't go away. The implications are that the Gulf Stream
> Flow disappeared/deviated/whatever in 5 years. This implies a fundamental
> mixing of the oceans during major climate changes, mixing which will screw
> up the rest of the predictions in KEA. (I treat these postings as my
> lectures-I only repeat myself if I feel the audience wasn't listening.)
> Note: for those of you interested in paleoclimatology: Smith et al 1997,
> the companion piece, Smith et al, 2000 (PALAIOS), provide an isotopic
> Rosetta Stone, a solution to the annoying effects of KIE (this is a
> which makes many coral isotopic climate records simply undependable).
> Precise water temperatures, any ocean, any coral, any depth. The "lines"
> paper, in PALAIOS, took corals from all over the world, used thousands of
> isotopic measurements to show that the slopes of lines in O-C space,
> independent of KIE, were a thermometer.
> After Dr. Kleypas' response, I went back, and I searched through that Am.
> Zool. volume, and By God I found it! In Kleypas et al, on p. 153, we see
> (refs removed to save typing) "...nutrient excess probably limits reefs
> indirectly by enhancing macroalgal competition for space, phtoplankton
> competition for light, and bioerosion." And that's all. Instead of
> to have "mentioned bioerosion several times as an important control on
> development," I think she should have 'fessed up, said "OK, we left it
> we'll do better next time. Can you help us?" Ain't going to happen. (By
> way, the Gattuso et al paper in that same volume is one of the nicest
> summaries of coral gas and nutrient metabolism I have read.)
> I'd like to go over some of this again. I do apologise in advance for some
> of the self-citations: there has already been too much of this in these
> exchanges. I do so only when  one of my rusty old beaters was the only one
> on the lot at the time...
> The classic studies on reef budgets were done in the early 70's, based on
> field work done (in some cases) commenced in the 60's. The results have
> never been challenged: bioerosion equals calcification, with large errors.
> (Where calcification spikes up, we get reefs-where it does
> There have been a few studies directly relating bioerosion rates to
> concentrations. Rose and Risk (1985-Mar Ecol 6: 345-363) found that
> of Cliona delitrix increased in lockstep with the abundance in the water
> column of fecal bacteria. (No phosphates, no nitrates-plain old poop.
> poop.)
> Since the early 70's, when those papers were done, coastal nutrient
> concentrations/eutrophication levels have AT LEAST doubled. In other
> bioerosion is now FAR MORE IMPORTANT than the corals! The treatment of
> subject in the Amer Zool volume simply exposes the huge lacuna in the
> skill-set of today's reef biologists.
> So reef monitoring programs that omit bioerosion are a joke, as are reef
> growth models. It is to be hoped that rapid readjustments are under way as
> we speak.
> But let us examine the role of bioerosion in calcification
> budgets/alkalinity reduction studies.
> Microborers have been around since the PreCambrian, and comprise several
> phyla: blue-green algae (yeah, I know, Cyanobacteria-but geologists still
> call them blue-greens), greens, reds, fungi...They are in every grain of
> sediment, every coral, every shell, every coral that has ever been stuck
> into a metabolic chamber...most of the destruction is done by the green
> algae, via secretion of short-chain organic acids, such as formic, oxalic
> (good for taking rust off cars), malic. As usual, the stoichiometry eludes
> me, but here is what I see:
>     -because they manufacture short organic acids thru photosynthesis, the
> CO2 balance may be close to a push (one in, couple out).
>     -their eroding activities, however, crank up alkalinity values, via a
> process that appears in the gas-exchange models as PS. In other words, the
> O2 production of the corals, which is calcification, is mixed with the O2
> production by alkalinity-pushers.
> That's just the greens. There is evidence that the blue-greens may be
> heterotrophic-like graduate students, there's no telling WHAT they do at
> night...the fungi are saprobic, dikaryomycotan anamorphs-common
> fungi. You have some in your fridge now, on the bottom shelf, at the back
> there. (Kendrick et al. 1982, Bull Mar Sci 32: 862). They invaded via
> beachrock or.....African dust!
> I had hoped that Bellamy and Risk (1982: Science 215: 1618-1619) would
> been more widely absorbed by calcification modellers: we found very large
> amounts of oxygen, produced by boring algae, stored in the tips of
> on the GBR. If you "ping off" a tip, not only will you see clouds of
> bubbles, you may even hear the hiss of escaping gas. (No, please don't do
> it!) Shasher and colleagues, in Israel, in a series of elegant experiments
> on "life in extreme environments", estimated that the amount of
> the metabolism, of boring algae lying directly under live coral tissue was
> small-so perhaps they may safely be ignored? No.
> On the contrary: the ones in corals are light-limited. In sediments and
> hardgrounds, they have a major impact. Tudhope and Risk (1985: J.
> Sedimentary Petrology 55: 440-447) estimated that boring algae dissolved
> between 18 and 30% of the TOTAL sediment input into GBR lagoons. These
> extremely conservative estimates, and the real value is undoubtedly
> In that paper, there is a section on the relevance of the results to
> whole-reef calcification estimates using alkalinity reduction techniques.
> 446: "...loss of carbonate from the reef system due to dissolution of
> sediments by microborers is a more important factor in whole-reef budgets
> than previously recognised"-and it remains unrecognised.
> I would invite KEA to explain to me, and the list, how the influence of
> microborers on gas exchange over reefs has been handled in their models.
> Finally, I am deeply distressed that my anguish at the demise of the
> ecosystem in which I have spent most of my life should be dismissed as
> at "my own reef issue being overshadowed" by the predictions in KEA.
> Firstly, I don't think their predictions are worth much-but far more
> importantly: I am as far as I know the only reef scientist who has had the
> courage to speak out in print against the factionalism that paralyses reef
> science (Risk 1999, Mar. FW Res 50: 831-837). It is unacceptable to me
> I be accused of the same turf-war mentality. It is unacceptable, and I am
> very angry about it.
> Message ends-thank you all for your  indulgence.
> ~~~~~~~
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**** <>< ******* <>< ******* <>< ******* <>< *******
Alan E. Strong
Acting Chief, Oceanic Research & Applications Division
Team Leader, Marine Applications Science Team (MAST)
Phys Scientist/Oceanographer
  NOAA Science Center -- RM 711W
  5200 Auth Road
  Camp Springs, MD 20746-4304
        Alan.E.Strong at
             301-763-8102 x170
              FAX: 301-763-8572

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