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Disaster and Recovery of the Fringing Reefs of North Jamaica
Reference
Crabbe, M.J.C. 2009. Scleractinian coral population size structures and growth rates indicate coral resilience on the fringing reefs of North Jamaica. Marine Environmental Research 67: 189-198.

Background
The author writes that "coral reefs throughout the world are under severe challenges from a variety of environmental factors including overfishing, destructive fishing practices, coral bleaching, ocean acidification, sea-level rise, algal blooms, agricultural run-off, coastal and resort development, marine pollution, increasing coral diseases, invasive species, and hurricane/cyclone damage."

What was done
Crabbe employed a number of demographic tools to analyze the resilience of the fringing reefs around Discovery Bay, Jamaica, by documenting the responses of their populations "to a number of environmental stressors, in particular hurricanes and the mass bleaching event of 2005," which he describes as "by far the major acute influence on the reef sites."

What was learned
The UK researcher reports "there was a reduction in numbers of colonies in the smallest size class for all the species at all the sites in 2006, after the mass bleaching of 2005, with subsequent increases for all species at all sites in 2007 and 2008." At Dairy Bull Reef, for example, he notes that "live coral cover increased from 13 5% in 2006 to 20 9% in 2007 and 31 7% in 2008," and that "live Acropora species increased from 2 2% in 2006 to 10 4% in 2007 and 22 7% in 2008."

What it means
The UK researcher concludes that his results "indicate good levels of coral resilience on the fringing reefs around Discovery Bay in Jamaica," which finding is rather stunning in light of the reefs having "suffered from long term human-induced chronic stressors, such as overfishing and land development," to which he also adds "die-off of the long-spined sea urchin" and "coral disease." In fact, it's amazing the corals were able to bounce back at all, in light of the many detrimental assaults on their growth and development. And in regard to this noteworthy feat, Crabbe states that he and a colleague "found a variety of clades of zooxanthellae, including clade C, in corals at Dairy Bull Reef (Crabbe and Carlin, 2007)," and he says that "the potential for symbiont shuffling, as we have found in 111 colonies of Acropora species from the Ningaloo Reef, Australia (Crabbe and Carlin, 2009), may be a factor in their recovery," citing the further work of Stat et al. (2008).

References
Crabbe, M.J.C. and Carlin, J.P. 2007. Industrial sedimentation lowers coral growth rates in a turbid lagoon environment, Discovery Bay, Jamaica. International Journal of Integrative Biology 1: 37-40.

Crabbe, M.J.C. and Carlin, J.P. 2009. Multiple Symbiodinium clades in Acropora species scleractinian corals from the Ninagloo reef, Australia. International Journal of Integrative Biology 5: 72-74.

Stat, M., Morris, E. and Gates, R.D. 2008. Functional diversity in coral-dinoflagellate symbiosis. Proceedings of the National Academy of Sciences USA 105: 9256-9261.

Reviewed 16 September 2009