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The Resiliency of a Tropical Eastern-Pacific Coral Reef
Reference
Zapata, F.A., Rodriguez-Ramirez, A., Caro-Zambrano, C. and Garzon-Ferreira, J. 2010. Mid-term coral-algal dynamics and conservation status of a Gorgona Island (Tropical Eastern Pacific) coral reef. International Journal of Tropical Biology and Conservation 58 (Suppl. 1): 81-94.

Background
The authors write that "few coral reef sites have been studied for sufficiently long periods to document their background variability, measure significant departures, and partition causal processes of change into natural and anthropogenic components," and in light of this fact, they devised and conducted a study that enabled them to do some of these things.

What was done
Working with data they obtained over the period 1998-2004 from 20 permanent transects at two sites on one of the largest and best developed coral reefs in the Colombian Pacific (La Azufrada reef on Gorgona Island), plus data obtained there even earlier by others, Zapata et al. developed an extended history that revealed some interesting aspects of the reef's resiliency.

What was learned
The four Colombian researchers report that comparisons with previous studies showed the reef at La Azufrada to have returned to "pre-disturbance (1979) levels of coral cover within a 10-year period after the 1982-83 El Niño, which caused 85% mortality," and that, subsequently, "the effects of the 1997-98 El Niño, indicated by the difference in overall live coral cover between 1998 and 1999, were minor (<6% reduction)." And they indicate that "despite recurrent natural disturbances, live coral cover in 2004 was as high as that existing before 1982 at La Azufrada."

What it means
Zapata et al. conclude that "the recent history of La Azufrada reef since coral reef studies began at Gorgona Island three decades ago (Prahl et al., 1979; Glynn et al., 1982) suggests a remarkable ability of this reef to recover from past perturbations," which are of the type (extreme El Niño-driven temperature increases leading to coral bleaching) that climate alarmists claim should be especially deadly, and from which coral recovery should not be expected.

Our conclusion? Nature, apparently, is full of surprises!

References
Glynn, P.W., von Prahl, H. and Gunl, F. 1982. Coral reef of Gorgona island, Colombia, with special reference to corallivores and the influence on community structural reef development. Anales del Instituto de Investigaciones Marinas de Punta Betín 12: 185-214.

Prahl, H. von, Guhl, F. and Grogl, M. 1979. Gorgona. Futura, Bogota, Colombia.

Reviewed 9 March 2011