Insights toward the future potential distribution of mangrove crabs in the Persian Gulf and the Sea of Oman

Mangroves are an ideal habitat for brachyuran crabs because of nutritional and shelter support. Using maximum entropy (MaxEnt) modeling technique, we projected the potential global distributions of 10 dominant species of mangrove crabs from the Persian Gulf and the Sea of Oman under future climate change. The highest species richness of mangrove crabs was in the Northeast Persian Gulf, including the Strait of Hormuz and Qeshm Island, as well as the North Sea of Oman. Our results revealed that depth and sea surface temperature (SST) were the most important drivers of distribution of mangrove crabs. The most potential suitable environments are located along the coastal areas of the Persian Gulf, and the Sea of Oman, where the depth is <16.89 m, temperature is between 27.70 and 28.08°C, salinity is between 37.21 and 40.61 PSS, and currents velocity is between 0.01 and 0.05 m⁻¹ for the present output models. Future distribution model outputs showed that, areas with depth <3.12 m, temperature between 28.53 and 28.92°C, salinity between 37.21 and 40.63 PSS, and current velocity between 0.01 and 0.05 m⁻¹ were the most suitable environments for future potential distributions of mangrove crabs. MaxEnt model outputs revealed that five species (50%) will expand and the remaining (50%) will shrink in their future distribution ranges. The model outputs predicted that some of the species might lose their habitat in future, and some might invade other ecosystem as invasive species. These findings thus highlight not only the vulnerability of mangrove crabs to habitat loss, but also alert their potential invasions to other ecosystems due to future climate changes. This outcome should be considered as a basic guideline for species management of mangrove systems.