Abstract The European green crab ( Carcinus maenas ) is a globally important invasive species. Since 1989, it has been spreading north from San Francisco Bay on the Pacific Coast of North America. Climate change is likely to lead to the species spreading further north into Alaskan and Arctic waters. Previous studies predicting its potential future distribution have focused on its range at the end of the century, under only one of multiple climate change scenarios. We used Bayesian Additive Regression Trees (BART) and benthic environmental variable predictors derived from the latest Intergovernmental Panel on Climate Change report to produce decadal predictions under four climate change scenarios; SSP1, SSP2, SSP4, and SSP5. We find that under all but the lowest emission scenarios, the European green crab will find suitable habitat as far north as the Seward Peninsula, and potentially, under the highest emission scenarios, into the Arctic Circle. This could have devastating consequences for the local ecology of the Pacific Coast of North America, for local economies dependent on fisheries, and for local communities, particularly indigenous communities. Increased monitoring in regions where green crab is likely to find favourable habitat could help with early detection, and potentially early functional eradication before populations establish themselves.
Villar et al. (Thu,) studied this question.