Multiple anthropogenic impacts, including bleaching from climate change-related thermal stress, threaten coral reefs. Protecting coral capacity to respond to the increase in future thermal stress expected with climate change can involve (1) protecting coral reefs with characteristics indicative of greater resistance and resilience to climate change, and (2) mitigating other anthropogenic impacts that are more likely to reduce coral resistance and resilience to climate change. Here we quantitatively compare possible priorities and existing recommendations for protecting coral response capacity to climate change. Specifically, we explore the relative importance of the relevant dynamics, processes, and parameters in a size-structured model of coral and zooxanthellae ecological and evolutionary dynamics given future thermal stress. Model results indicate that protecting diverse coral communities is critical, and protecting communities with high abundances of more thermally tolerant coral species and symbiont types secondary, to long-term coral persistence. A sensitivity analysis suggests greater relative importance of mitigating additional anthropogenic impacts that affect coral-macroalgal competition, early coral life history stages, and coral survivorship (compared to reproduction, growth, and shrinkage). Finally, model results with temperature trajectories from different locations indicate that protection of, and connectivity to, low-thermal-stress locations may enhance coral response to climate change.

Last Updated: 2008-09-04