Environmental factors driving the distribution of the tropical coral Pavona varians: Predictions under a climate change scenario

Abstract

Climate change causes shifts in the geographical distribution boundaries of many organisms. Modelling techniques predict the distribution of species by relating climatic and physical factors with species' presence records, including potential extinction areas and new potential areas of colonization, under predicted climatic scenarios. In this study, we initially explored which environmental variables most influenced the distribution of Pavona varians, a hermatypic coral from the equatorial Indian and the Pacific Ocean, which is categorized as ‘Least Concern’ by the UICN. The most influential variables were the minimum and maximum sea surface temperature, the diffuse water attenuation and the cloud cover. These variables were used to predict habitat suitability of P. varians under a current and a future (A1B IPPC) scenario using MaxEnt. Despite P. varians is an opportunistic species, with a well-known resistance to environmental stress, the model predicted a massive decline in the suitability of its habitat in all areas by the year 2100. The information obtained by this study can be used to support the conservation decision making process to improve the preservation of the species.