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Coral Reef Decline: One Must Understand Its Cause To Properly Treat the Problem
Volume 7, Number 39: 29 September 2004

In introducing their seminal report on this important topic, Pandolfi et al. (2003) begin by noting that "the long-term historic sequence of ecosystem decline is unknown for any reef, thereby obscuring the potential linkage and interdependence of the different responsible factors that must be unraveled for successful restoration and management."  Hence, they take their own advice and reconstruct multi-century histories of fourteen coral reefs from around the world, employing a common set of consistent criteria, before attempting to prescribe a restorative treatment program.

This exercise revealed, in the words of the twelve contributing scientists, that "all reefs were substantially degraded long before outbreaks of coral disease and bleaching," which phenomena currently garner the lion's share of attention when it comes to assessing reef health.  In fact, they report that the "degradation of coral reef ecosystems began centuries ago," when, of course, the world was still in the midst of the Little Ice Age.

So how far down the slippery slope that leads to extinction are the world's coral reefs currently?  And what has propelled them to this unfortunate position?

Pandolfi et al.'s analysis revealed that the 14 coral reefs they studied are fairly evenly distributed between just under 30% to just under 80% of the way from what they call "pristine" to "ecologically extinct," and they find that "the most important guilds influencing the trajectories of decline are large herbivores and carnivores," which they report "were almost nowhere pristine by the beginning of the 20th century, when these guilds were already depleted or rare in more than 80% of the 14 regions examined."

With regard to the present, the scientists note that "recent widespread and catastrophic episodes of coral bleaching and disease have distracted attention from the chronic and severe historical decline of reef ecosystems."  Noting that "all of the reefs in our survey were substantially degraded long before the first observations of mass mortality resulting from bleaching and outbreaks of disease," they conclude that "the only reasonable explanation for this earlier decline is overfishing, although land-derived pollution could have acted synergistically with overfishing in some localities."

In describing the practical implications of their findings, Pandolfi et al. say that "coral reef ecosystems will not survive for more than a few decades unless they are promptly and massively protected from human exploitation," which is what we have advocated from the very beginning of this discussion on our website (see, for example, our Editorials of 1 Jan 1999, 19 Sep 2001, and 26 Mar 2003).  It should be abundantly clear to most thinking people, therefore, that to claim that we must halt global warming to save these precious ecosystems, as most climate alarmists do, is to look beyond the mark and therefore likely fail to implement the more mundane (but absolutely necessary) protective measures that must be put in place now.  Taking the other course may well give some folks a warm fuzzy feeling, but it will consign earth's corals to oblivion.  We cannot be distracted by tilting at windmills when a clear and present danger is staring us right in the face.

Sherwood, Keith and Craig Idso

Reference
Pandolfi, J.M., Bradbury, R.H., Sala, E., Hughes, T.P., Bjorndal, K.A., Cooke, R.G., McArdle, D., McClenachan, L., Newman, M.J.H., Paredes, G., Warner, R.R. and Jackson, J.B.C.  2003.  Global trajectories of the long-term decline of coral reef ecosystems.  Science 301: 955-958.