Invasive species threaten Antarctica amid climate-driven ice loss

According to "Global Change Biology," the increasing melting of sea ice facilitates the transport of organic and plastic waste, enabling invasive species from the Southern Hemisphere to reach Antarctica.

Scientists from the University of New South Wales (UNSW) in Australia conducted a 19-year study on the movement of floating debris, considering ocean currents and wave action.

The analysis shows that objects from Macquarie Island, located south of New Zealand, took the least time to reach Antarctica—less than nine months. Meanwhile, waste from South America had the longest travel time.

Researchers also identified coastal areas of Antarctica that are most vulnerable to invasion by alien species. Most of these areas are near the Antarctic Peninsula, which has relatively low seawater temperatures due to the frequent disappearance of sea ice. These conditions favour the expansion of invasive species.

"Sea ice is very abrasive and acts as a barrier for many non-native species. But with the recent decline in Antarctic sea ice, living things floating at the surface or attached to debris could have an easier time colonizing the continent," emphasized Dr. Hannah R. S. Dawson, currently affiliated with the University of Tasmania, who led the study.

"If they colonize Antarctica, marine ecosystems there could change dramatically. These factors make it a likely area for non-native species to first establish, which may have big impacts on ecosystems," she added.