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The Recovery of Three Caribbean Corals Following a Simulated Bleaching Event

Paper Reviewed
Levas, S., Schoepf, V., Warner, M.E., Aschaffenburg, M., Baumann, J. and Grottoli, A.G. 2018. Long-term recovery of Caribbean corals from bleaching. Journal of Experimental Marine Biology and Ecology 506: 124-134.

It has been postulated that temperature-driven mass coral bleaching events in the Caribbean will increase in frequency and intensity in the coming decades in response to human-induced global warming, possibly driving some coral species to extinction. Yet despite such predictions, Levas et al. (2018) write that "it remains poorly understood how quickly Caribbean corals can recover from bleaching."

Hoping to advance scientific understanding of this knowledge gap, the team of six researchers set out to explore the heat stress response and recovery of three key Caribbean corals, Porites divaricata, Porites astreoides and Orbicella faveolata. More specifically, they subjected samples of these coral species to 15 days of elevated seawater temperature to induce heat stress (bleaching) and compared their physiology and biogeochemistry against non-bleached control corals after 0, 1.5 and 11 months of in situ recovery.

And what did their experiment reveal?

In the words of the authors, "despite all treatment corals having significantly reduced endosymbiont concentrations and calcification at some point during the first 1.5 months [of recovery], all physiological variables in treatment corals of all three species had recovered by 11 months." And in light of this encouraging observation, Levas et al. conclude that their work suggests these corals "are capable of surviving and recovering" from bleaching events of this magnitude (3 to 4-degree heat weeks relative to control corals, which was "similar to heat stress levels measured during the 1998 bleaching event in the Caribbean").

Posted 21 November 2018