The Coral Triangle reef system (CT) is the epicenter of marine biodiversity and one of the most threatened ecosystems in the world. To assess the reef- and network-scale response of corals to thermal perturbation in this region, we have developed a spatially explicit metacommunity model based on coral-algal competition coupled with seasonal larval dispersal. With this model, we have explored the sensitivity of the CT system to a range of future temperature regimes, from 0.5 to 2.0 degree C increase in the system by 2054.
Results/Conclusions
Time to reef collapse and total change in percent coral cover varied widely across the region, in response to this warming, with some reefs experiencing local extinction while others remaining virtually unchanged. The magnitude of thermal stress as well as recruitment-based metrics are significant drivers of these patterns, signifying the importance of linking ecological processes across multiple spatial scales to fully characterize the resilience of a reef network perturbed by climate change. Additionally, we have explored heat tolerance as a heritable trait throughout the CT to facilitate coral adaptation. We have found that warm-adapted reefs can provide a regional protective effect against bleaching-related mortality through larval connectivity. Last, the interaction between intra- and inter-patch processes under different magnitudes of thermal stress can be complex and nuanced, resulting in counterintuitive coral cover trajectories. This framework can be extended to accommodate a wide array of life history characteristics that can further elucidate the adaptive capacity of corals.