ssdm: An r package to predict distribution of species richness and composition based on stacked species distribution models

There is growing interest among conservationists in biodiversity mapping based on stacked species distribution models ( SSDM s), a method that combines multiple individual species distribution models to produce a community‐level model. However, no user‐friendly interface specifically designed to provide the basic tools needed to fit such models was available until now. The “ ssdm ” package is a computer platform implemented in r providing a range of methodological approaches and parameterisation at each step in building the SSDM : e.g. pseudo‐absence selection, variable contribution and model accuracy assessment, inter‐model consensus forecasting, species assembly design, and calculation of weighted endemism. The object‐oriented design of the package is such that: users can modify existing methods, extend the framework by implementing new methods, and share them to be reproduced by others. The package includes a graphical user interface to extend the use of SSDM s to a wide range of conservation scientists and practitioners.