The case of a threatened medicinal tree with optimistic prospects under climate change

Abstract

Climate change is an increasing cause of biodiversity loss. The extinction of species is the most dramatic case, but also a large number of species will be forced to migrate due to the loss of habitat. We conducted a study on the current distribution of Warburgia salutaris (Canellaceae), one of the wild harvested medicinal plant species endangered through the effects of bark harvesting and land transformation, as well as the potential future distribution, extent of occurrence and habitat quality under climate change. For that, we used current occurrence data and uncorrelated environmental variables for the years 2040–2100, under four future Shared Socio-economic Pathways (SSPs) scenarios (SSP126, SSP245, SSP370, and SSP585) for four general climatic models (GCMs). A mobility-oriented parity was conducted to identify extrapolation risk. Future prediction indicated a considerable increase of highly suitable areas under all SSPs scenarios in almost all the GCMs in southern Mozambique compared to the current distribution. Overall, the suitable area and its habitat quality increased steadily in 80 years compared to the current situation. Hence, climate change could not be argued as a threat to W. salutaris for the studied period. In this context, actions such as reintroduction and cultivation to provide alternative sources of bark supply, could be capitalised to alleviate pressure on natural populations while allowing their recovery and the establishment of new core populations.