Invasive species a huge threat to sparse ecosystems, scientists report
FRISCO — The tiny ice-free fringes of Antarctica are especially prone to ecosystem disruption, including invasive species, an Australian science team warned earlier this year after taking a close look at how human use is concentrated in those slivers of dry land.
Antarctica has over 40,000 visitors a year, and more and more research facilities are being built in the continent’s tiny ice-free area. Most of the Antarctic wildlife and plants live in the ice-free areas – and this is also where people most visit.
Most tour operators in Antarctica follow strict guidelines set to protect ecosystems, including at least basic decontamination procedures, but those measures might not be enough, especially as global warming makes ice-free zones more susceptible to invasive species.
Overall, the melted edges of Antarctica need better protection from human activities, the scientists concluded in their study, published in PLoS Biology.
Some fragile ecosystems could be lost forever, according to Professor Hugh Possingham, of the National Environmental Research Program’s Environmental Decisions Hub at the University of Queensland, who said that Antarctica is one of the last places on Earth that has no cities, agriculture or mining.
“It is unique in this respect – a true wilderness. If we don’t establish adequate and representative protected areas in Antarctica this unique and fragile ecosystem could be lost,” Professor Possingham said.
“Although we show that the risks to biodiversity from increasing human activity are high, they are even worse when considered together with climate change. This combined effect provides even more incentive for a better system of area protection in Antarctica,” he said.
One of the researchers from the collaborative study, Professor Steven Chown from the School of Biological Sciences at Monash University, said the ice-free area contains very simple ecosystems due to Antarctica’s low species diversity. This makes its native wildlife and plants extremely vulnerable to invasion by exotic species.
“Antarctica has been invaded by plants and animals, mostly grasses and insects, from other continents. The very real current and future threats from invasions are typically located close to protected areas,” Professor Chown said.
“Such threats to protected areas from invasive species have been demonstrated elsewhere in the world, and we find that Antarctica is, unfortunately, no exception.”
All 55 areas designated for protection lie close to sites of human activity. Seven are at high risk for biological invasions, and five of the distinct ice-free eco regions have no protected areas at all.
“Most of Antarctica is covered in ice, with less than one per cent permanently ice-free,” said Dr Justine Shaw of the National Environmental Research Program’s Environmental Decisions Hub at the University of Queensland. “Only 1.5 per cent of this ice-free area belongs to Antarctic Specially Protected Areas under the Antarctic Treaty System, yet ice free land is where the majority of biodiversity occurs,” said Shaw, calling the ‘last wilderness on Earth’ is one of the planet’s least-protected regions
The study shows that protected areas in Antarctica currently fall well short of the Aichi Biodiversity Targets – an international biodiversity strategy that aims to reduce threats to biodiversity, and protect ecosystems, species and genetic diversity. If the frozen continent were a country, it would rank in the lowest 25 percent in terms of protected areas.
Shaw said many people think that Antarctica is well protected from threats to its biodiversity because it’s isolated and no one lives there, however the study clearly shows threats to Antarctic biodiversity.
“We need to establish protected areas that are representative of Antarctic biodiversity to protect a diverse suite of native insects, plants and seabirds, many of which occur nowhere else in the world,” she said.
“We also need to ensure that Antarctic protected areas are not going to be impacted by increasing human activities, such as pollution, trampling or invasive species,” she added.