Maritime traffic connects Antarctica’s fragile coasts to global ecosystems

Summary

Antarctica, a remote wilderness and long considered pristine, is increasingly exposed to the negative effects of human activity transported by ships, and in particular the introduction of invasive species. Here we provide a comprehensive quantitative analysis of vessel movements in Antarctic waters and a spatially explicit assessment of the risk of introduction of marine non-native species to all Antarctic waters. We show that ships pass through Antarctica’s isolating natural barriers, connecting it directly via an extensive network of maritime activity to all parts of the world, especially South Atlantic and European ports. Ship visits are more than seven times higher in the Antarctic Peninsula (particularly east of Anvers Island) and the South Shetland Islands than elsewhere around Antarctica, together accounting for 88% of visits in the Southern Ocean ecoregions. Contrary to expectations, we show that while the five recognized “Gateway Cities to Antarctica” are important last ports of call, especially for research and tourist vessels, 53 additional ports have had ships leaving directly for Antarctica from 2014 to 2018. We identify ports outside Antarctica. where biosecurity interventions could be implemented most effectively and the most vulnerable Antarctic sites where monitoring programs for high-risk invaders should be established.