[Coral-List] Fwd: Conservation versus restoration of coral reefs
allison.billiam at gmail.com
Tue Feb 19 12:52:09 EST 2008
Thanks for that significant information. I had discounted the free-standing
breakwall because until you mentioned it, I had the impression that it had
not been entirely completed before the 1998 bleaching event. I did not know
of the three small cones and could not even find them on your website.
Despite that information gap, I don't think I was completely incorrect – see
Btw: I'd be pleased to take up your invitation and visit your artificial
reefs sometime. Perhaps you would suggest it to Azeez. The free-standing
breakwall function is especially intriguing.
Here is my response to your last. Please excuse me if this seems elementary
but I want to make sure I have got it right. An experiment aims to control
the effects of all variables other than those under investigation. Whatever
the other alleged attributes of the technology you are employing might be,
it seems that stimulation of coral growth and resistance to bleaching
mortality, produced directly or indirectly by the electrical current, is the
main effect relevant to this discussion. To test this a sufficient number of
identical replicate and control structures should be randomly dispersed on
the reef and transplanted corals randomly selected and affixed to the
structures, all within a very short time interval. If the requirement for
identical replicate structures and near simultaneous initiation is relaxed,
we are still stuck with no controls if the effect of electricity is to be
evaluated. I hope you will now tell me that such structures were in place
prior to and during 1998. The general point is that until an accessible,
clear, precise, description of your "experiment" is available, complete with
aims, falsifiable hypotheses and detailed experimental design, the validity
of your stated results cannot be critically assessed. From another
perspective, because you are promoting this approach as a conservation
superlative and soliciting money that could otherwise be spent on other
conservation approaches, the onus is on you to provide satisfactory evidence
that can be critically reviewed. Until this is done it will seem more like
snake oil than science. Why hasn't it been set out on your website or better
still in a peer reviewed article? With regard to this aspect, your mention
of the artificial reef tests on Galu Faru reef is apposite.
Your description of an artificial reef project as "…a couple of hundred
meters of concrete superhighway roadbed…" seems to approximate the one set
up by Newcastle on Anchorage Reef. I know of no other of that vintage. It
comprised 12 randomly dispersed units of which nine, each about 7-8 m long
were vaguely like roadbed and three were somewhat larger and made of one
meter hollow cubes. These three must have stood out from the rest as
distinctly unsuperhighway-like, even by SUV standards. That all 360 tons of
concrete and steel were imported from the UK is not the issue here.
With respect to the above-mentioned reef, the assertion that "Thousands of
corals had been cemented to it, but virtually all of them died BEFORE the
bleaching." is questionable for several reasons (I assume that the "it" is a
typo and you meant "them").
1). Over the years I have frequently looked in on the Anchorage Reef site.
Your assertion that most of the corals died before the 1998 bleaching is
astonishing, but not inexplicable if only a few of the widely dispersed
sites were visited. Although many units supported flourishing coral carpets,
some were impoverished, particularly those with low topographic relief (and
possibly resembling "superhighway roadbed"). Perhaps you were exposed to
only such units? When, exactly, did you visit the site, or did someone else
provide you with the video – not necessarily of all of the units?
2). Only three of the twelve units bore coral transplants and these
transplants totaled hundreds, not thousands. The rest of the "thousands of
corals" you mention seeing got there under their own larval steam, implying
that if one is compelled to built artificial reefs of any sort,
transplantation is not only unnecessary, but with its financial and carbon
costs and largely unquantified effects on the donor reefs, undesirable.
Details of the Newcastle project's aims, methods, research design, and
results are readily accessible (Clark & Edwards, 1994, 1999), as is their
largely negative assessment of the artificial reef and transplant approach
for reef rehabilitation (Clark & Edwards, 1999; Edwards & Clark, 1999).
Clark, S. and A. J. Edwards (1994). "Use of artificial reef structures to
rehabilitate reef flats degraded by coral mining in the Maldives." Bulletin
of Marine Science 55(2-3): 726-746.
Clark, S. and A. J. Edwards (1999). "An evaluation of artificial reef
structures as tools for marine habitat rehabilitation in the Maldives."
Aquatic Conservation: Marine and Freshwater Ecosystems 9(1): 5-21.
Edwards, A. J. and S. Clark (1999). "Coral Transplantation: A Useful
Management Tool or Misguided Meddling?" Marine Pollution Bulletin 37(08-12):
Edwards, A. J., S. Clark, et al. (2001). "Coral bleaching and mortality on
artificial and natural reefs in Maldives in 1998, sea surface temperature
anomalies and initial recovery." Marine Pollution Bulletin 42(1): 7-15.
Best wishes to you too,
On Feb 17, 2008 6:38 PM, Thomas Goreau <goreau at bestweb.net> wrote:
> Dear Bill,
> Your statements about controls and replicates in our project are
> completely incorrect. I guess you have not seen them yourself? One electric
> reef structure (roughly 5 m high, 4 m wide at the base) on the fore reef
> slope had about 16 times higher survival than surrounding reefs, three more
> smaller projects (each about 3 m high, and 2x2 meters base) in the same
> habitat had similar results, and one structure on the reef flat (50 m long,
> 1.5 m high, about 5 m wide) had about 50 times higher survival than
> surrounding reefs. The larger projects had many hundreds of corals on them,
> not just a few. Another large project was done after bleaching, and so has
> on bearing on bleaching survival. For controls we compared thousands of
> corals that had previously been cemented on to concrete blocks and dead
> reef. Even though they were all doing well prior to bleaching, every single
> one of the control coral transplanted using conventional methods died, i.e.
> 100% mortality and 0% survival, compared to around 1-5% survival of natural
> corals on the nearby reef, and 50-80 percent survival on the electric reefs.
> We have hundreds of photographs and around 50 hours of digital video
> transects of the electric reefs, natural reefs, and control transplants
> taken before and after bleaching that document these results. Typical video
> of all three before during and after were presented at ICRI.
> I'm not sure if the artificial reef project by the World Bank you are
> referring to was done before or after the bleaching? If after it has no
> bearing on survival from bleaching. The only other reef restoration project
> I looked at in North Male Atoll, was where a couple of hundred meters of
> concrete superhighway roadbed was laid on a dead reef. Thousands of corals
> had been cemented to it, but virtually all of them died BEFORE the
> bleaching. I have video footage of the entire length of these projects, and
> the contrast with our results on the electric reefs couldn't possibly be
> more dramatic. I have not had the money to get back to the Maldives for the
> last 7 years, but since you live there in the same atoll as both of these
> projects, you can easily contrast them yourself. I think you will still find
> the difference extraordinary and look forward to your personal observations
> of the coral and fish abundance on our projects compared to the concrete
> planting projects.
> Best wishes,
> On Feb 17, 2008, at 6:11 PM, William Allison wrote:
> Dear Tom,
> In your message of Feb 2 (repeated Feb 13) you assert that the major
> funding agencies are neglecting your product because they have given up on
> coral reef restoration. Without condoning it, I can think of at least one
> artificial reef project in Maldives funded by an arm of the World Bank in
> recent years. Perhaps there is another explanation for your situation.
> Despite the extraordinary Maldives bleaching results presented in your
> message, interest may be low because the experimental design cannot sustain
> the conclusions. In this case there was one experimental unit (a dome made
> of steel rod grid to which corals were tied and the whole subjected to
> electrical input). There were no replicates, there were no controls.
> Proceeding from basic experimental design principles, valid inferences about
> an experimental effect are not possible from this setup. Perhaps you should
> work on that aspect.
> I refer specifically to this segment of your message:
> >> >> There is only one method known that can keep corals alive under
> >> >> high temperatures that would ordinarily kill them. In the Maldives
> >> >> in 1998 the corals we were growing with our electrical trickle
> >> >> charging method had 16 to 50 times higher survival than
> >> >> surrounding reefs (Please note that is TIMES higher survival, not
> >> >> PERCENT. See T. Goreau, W. Hilbertz, & A. Azeez Hakeem, 2000,
> >> >> Increased Coral and Fish Survival on Mineral Accretion Reef
> >> >> Structures in the Maldives after the 1998 Bleaching Event,
> >> >> International Coral Reef Symposium, abstracts p. 263). Our corals
> >> >> bleached too, because they were exposed to the same temperatures,
> >> >> but they did not die,
> Bill Allison
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