Ships might bring invasive species to Antarctica, study finds

Written by Oceanographic Staff

Antarctica’s marine ecosystems are threatened by invasive species from around the world that hitchhike on ships, a recent study found.

The isolated wilderness of Antarctica has long supported unique ecosystems and species, while being the only marine region in the world that hasn’t had any biological invasions. A new study, however, has now established that increasing ship activities related to tourism, fishing, research and supply not only expose Antarctica to human impacts, but also have the potential to bring invasive species to the region through a process, called biofouling.

A team of researchers from the University of Cambridge and the British Antarctic Survey found that increasing ship traffic around the continent has the potential to deliver foreign marine organisms into the isolated ecosystems of the region. Furthermore, increasing temperatures due to climate change are “removing physiological barriers to potential invasive nonnative species”, according to the study, published in the Proceedings of the National Academy of Sciences.

By using satellite data and international shipping databases, the research team was able to identify how heavy ship traffic is in the region and where the ships embark from exactly. The study revealed that ships from around 1,500 international ports visit isolated Antarctica, while the most frequent routes were between Antarctica and South American and Northern European ports, as well as ports in the western Pacific Ocean.

Increasing ship traffic directly translates to an increased potential for ‘biofouling’, a process that describes marine species such as mussels, barnacles, algae and crabs clinging to the ship’s hull. “Invasive, non-native species are one of the biggest threats to Antarctica’s biodiversity – its native species have been isolated for the last 15-30 million years. They may also have economic impacts, via the disruption of fisheries,” said Professor David Aldridge in the Department of Zoology at the University of Cambridge, a co-author of the report.

The study further found that research accounted for 21% of visits to the region, while fishing accounted for 7% and tourism for 67%. While tourism is regulated in the region and ships have to adhere to strict biosecurity protocols, the study calls for stricter biosecurity protocols and environmental protection measures due to the fact that these ships travel all over the world and have the potential for biofouling.

The study calls for “addressing both climate change and direct, localized human impact” to tackle the issue. Furthermore, the researchers think that control measures will have to extend beyond the current gateway ports of Cape Town, Christchurch, Ushuaia, Punta Arenas and Hobart.

“This is the last place in the world where we don’t have marine invasive species,” lead researcher Arlie McCarthy from the University of Cambridge told the BBC. “So we have an opportunity to protect it.”

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Photography courtesy of Unsplash.

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