Disparity in responses of Honduran and Indonesian coral reef systems to global warming

Coral reef ecosystems have been rapidly altered by anthropogenic warming, posing significant threats to marine biodiversity. However, alterations of the benthic configurations of coral reefs under global warming likely vary through space given local-scale variation in environmental conditions and ecosystem processes. Here, we examine the responses of coral reef benthic configurations under global warming in two independent coral reef ecosystems from Honduras and Indonesia. Using Monte Carlo Markov Chain Generalised Linear Mixed models, our findings reveal that at the Honduras sites, global warming significantly drove reductions in sand, sponge and coral rubble coverage, while bare rock coverage increased. Conversely, the Indonesia sites only showed increases in sponge coverage and decreases in rock coverage associated with water warming. These strong disparities seem to have been driven by global warming only at the Honduras sites, but not at the Indonesia sites. This suggests that the Indonesia sites of the Wakatobi National Park (WNP) may be resistant to compositional changes under global warming. We suspect the resistance to compositional change at the WNP is driven by disparate ecosystem processes between the Honduras and Indonesia sites which enhances resilience to disturbance, such as water warming. Furthermore, there is potential indication that abiotic processes comparatively shelter coral reefs of the WNP from rising temperatures, however, this facet would need further exploration. Given the resistance to compositional change of coral reefs within the WNP, this region could potentially harbour critical biodiversity as global warming continues to decimate coral reefs throughout the tropics.