Map of death: spatially explicit mortality of the grey wolf

Death is an inherently spatial process. It happens to someone, somewhere, but often remains undetected in nature. Death is also the primary means by which humans regulate wildlife populations. Using a novel analytical method that accounts for the cryptic nature of the fate of individuals and one of the world's most comprehensive non-invasive genetic monitoring datasets, we were able to map cause-specific mortality of the entire Scandinavian grey wolf (Canis lupus) population despite the fact that most mortality events (mean = 65%; [95% CrI: 50.3-76.8%]) remained undetected. Our analysis revealed strong spatial variation in mortality with, for example, areas with a high risk of mortality linked with the current wolf management policies. Furthermore, we showed that the risk of legal mortality increased, while the risk of mortality due to causes other than legal mortality decreased with local wolf population density. This illustrates the complex interactions between spatial determinants and cause-specific mortality and therefore the importance of considering spatial variation when estimating mortality. Maps of mortality can inform wildlife management and conservation by capturing an elusive process in population dynamics as it unfolds in time and space.