Climate change threat: Invasive species looming over Antarctica

Climate warming may cause significant changes in Antarctica. Scientists are concerned that many invasive species may reach this cold continent.

According to "Global Change Biology," due to the increasing melting of sea glaciers, organic and plastic waste enables 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 of floating debris trajectories, 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 travelled the longest.

Researchers also identified coastal areas of Antarctica that are most vulnerable to invasion by alien species. Most of them end up near the Antarctic Peninsula, which is characterised by relatively low sea water 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 colonising the continent," emphasised Dr Hannah R. S. Dawson (currently affiliated with the University of Tasmania), who led the study.

"If they colonise 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.