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Antarctica: Invasive species ‘hitchhiking’ on ships

Antarctica: Invasive species ‘hitchhiking’ on ships


Species from around the world that are “hitching a lift” on ships threaten Antarctica’s pristine marine ecosystem.


That is the conclusion of a study tracking research, fishing and tourist vessels that routinely visit the protected, otherwise isolated region.

It revealed that ships from 1,500 ports around the globe visit Antarctica.

“These ships travel all around the world,” explained lead researcher Arlie McCarthy from the University of Cambridge.

“It means that almost anywhere could be a potential source for invasive species.” Those non-native species, she explained, “can completely change an ecosystem”.

“They can create entirely new habitats that would make it harder for those amazing Antarctic animals to find their own place to live.”

Penguins
Antarctica’s coasts are home to many endemic species that have been isolated for millions of years

The scientists say that more stringent measures are needed to ensure that ships do not bring species that could disrupt Antarctica’s fragile habitats.

The research team, from the British Antarctic Survey and the University of Cambridge, used satellite data and international shipping databases to work out the weight of Antarctic traffic – and the origin of those ships.

“What was really surprising was that they don’t just have one home port that they go back and forth to,” said Ms McCarthy.

Instead, the global movement of vessels links otherwise isolated parts of Antarctica to more than 1,500 ports all around the world.

Clinging on

Any marine species that can cling to the hull of the ship and survive the journey to Antarctica could pose an invasive threat.

Creatures, including mussels, barnacles, crabs and algae, are of particular concern, because they attach themselves to hulls, in a process termed “biofouling”.

'Biofouling' - marine organisms clinging to ships - can be seen here in a water discharge outlet on the hull of an Antarctic-going research vessel
‘Biofouling’ – marine organisms clinging to ships – can be seen here in a water discharge outlet on the hull of an Antarctic-going research vessel

Mussels, for example, can survive in polar waters and spread easily, threatening marine life on the seabed. Their water filtering alters the marine food chain and also the chemistry of the water around them.

“This is the last place in the world where we don’t have marine invasive species,” explained Ms McCarthy. “So we [still] have an opportunity to protect it.”

Professor David Aldridge from the University of Cambridge explained: “Antarctica’s native species have been isolated for the last 15-30 million years.”

This makes invasive species one of the biggest threats to its biodiversity. And, as Prof Lloyd Peck from the British Antarctic Survey added, “your chance of losing a species that is completely unique is much higher in the Antarctic”.

Tourist traffic

Tourism is regulated in the region; tourist ships have to follow biosecurity protocols. But this study revealed that tourism accounted for 67% of visits to Antarctic locations (followed by research, which accounted for 21% and fishing, 7%).

Researchers going ashore in Antarctica

According to the International Association of Antarctic Tour Operators, the 2019/20 season saw more that 70,000 people visit the region. And while the industry has been disrupted by the pandemic, that number has been increasing steadily since the first few hundred visitors from Chile and Argentina arrived in the South Shetland Islands in the 1950s.

It is an increase, say researchers, that has other consequences.

Ms McCarthy told BBC News: “Anywhere these ships go, we see other kinds of human impact on the environment, whether that is accidental release of waste, pollution, collisions with wildlife or noise disturbance.”

Prof Peck said Antarctic tourism was both “positive and negative”. “They are a big part of the number of visits [to the continent] and therefore could bring [non-native species] in.

“But the tour operators are very interested in the environment and take a lot of security measures.”

The British Antarctic Survey uses sniffer dogs to search for rats or mice aboard research vessels
The British Antarctic Survey uses sniffer dogs to search for rats or mice aboard research vessels

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Ship paint fragments were found to make up most of the samples the scientists found - SWNS

SCIENTISTS STUDYING MICROPLASTICS IN ANTARCTICA DISCOVER… IT ALMOST ALL CAME FROM THEIR SHIP


Scientists studying the origins of microplastics in Antarctica have discovered that 89 per cent of the samples they analysed came from the paint on their own ship.


More broadly, biosecurity measures to protect Antarctica – such as cleaning ships’ hulls – are currently focused on a small group of recognised Antarctic “gateway ports”.

But since this study revealed that many more ports around the world are linked to the region, the British Antarctic Survey is calling for “improved biosecurity protocols” and environmental protection measures to protect Antarctic waters. This means inspecting ship hulls with cameras and cleaning them more frequently.

Prof Peck said this was particularly important “as ocean temperatures continue to rise due to climate change”. He added: “we know something will arrive if we leave things as they are”.

Source:

Victoria Gill at CNN



Antarctic Ice Shelf Could Collapse Within Five Years, Causing Dangerous Sea Level Rise

Antarctic Ice Shelf Could Collapse Within Five Years, Causing Dangerous Sea Level Rise


A crucial ice shelf in Antarctica is at risk of collapse within as little as five years, scientists at a meeting of the American Geophysical Union said on Monday.


The Thwaites Eastern Ice Shelf, which holds a third of the crucial Thwaites Glacier in place, has been weakening and has developed cracks, satellite images showed. If the glacier, which is about the size of Florida and the widest on Earth at 80 miles across, were to fall into the ocean, sea levels would rise over two feet. At its current melting rate, the glacier accounts for about four percent of annual global sea level rise.

“The cracks in the Antarctic ice shelf are similar to those in a car windshield, where a slowly growing crack reveals that the windshield is weak and a slight bump to the vehicle could prompt the windshield to immediately break apart into hundreds of pieces of glass, according to Oregon State University glaciologist Erin Pettit,” reported Emma Newburger of CNBC.

“This eastern ice shelf is likely to shatter into hundreds of icebergs,” said Pettit, as reported by The Washington Post. “Suddenly the whole thing would collapse.”

Warming ocean temperatures, due in part to climate change, caused the wearing away of the ice shelf. Its collapse wouldn’t cause global sea levels to rise right away, “But when the shelf fails, the eastern third of Thwaites Glacier will triple in speed, spitting formerly landlocked ice into the sea. Total collapse of Thwaites could result in several feet of sea level rise, scientists say, endangering millions of people in coastal areas,” Sarah Kaplan of The Washington Post reported.

“We are already on track for sea level rise in the next several decades that will impact coastal communities worldwide,” said Pettit, as reported by CNBC. “We can’t reverse this sea level rise, so we need to consider how to mitigate it and protect our coastal communities now.”

Research by Pettit and Ted Scambos, a University of Colorado Boulder glaciologist and lead principal investigator of the International Thwaites Glacier Collaboration, shows that the ice shelf is losing its connection to the undersea mountain that’s been keeping it in place “against the ice river at its back. Even if the fractures don’t cause the shelf to disintegrate, it is likely to become completely unmoored from the seafloor within the next decade,” reported Kaplan.


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“We’re watching a world that’s doing things we haven’t really seen before, because we’re pushing on the climate extremely rapidly with carbon dioxide emissions,” said Scambos, as reported by ScienceNews. “It’s daunting.”

If the ice shelf collapses, a process called ice cliff collapse, never before seen in Antarctica, may be instigated, “in which towering walls of ice that directly overlook the ocean start to crumble into the sea,” Kaplan reported.

According to Anna Crawford, a glaciologist at the University of St. Andrews, “if it started instantiating it would become self-sustaining and cause quite a bit of retreat for certain glaciers,” The Washington Post reported.

While Crawford’s models show a domino effect of that kind is possible, “it’s unlikely to happen in the immediate future,” she said.

“But what we’re seeing already is enough to be worried about,” Crawford said. “Thwaites is kind of a monster.”

Source:

Ecowatch



Scientists studying microplastics in Antarctica discover… it almost all came from their ship

Scientists studying microplastics in Antarctica discover… it almost all came from their ship


Scientists studying the origins of microplastics in Antarctica have discovered that 89 per cent of the samples they analysed came from the paint on their own ship.


The researchers had initially been shocked to find such large concentrations of microplastics in such a remote expanse of water in the Southern Ocean.

However, when they studied the samples in a laboratory they were able to confirm that a large percentage came from flakes of paint from their own vessel.

Microplastics are small plastic pieces, less than five millimetres long, and are known to be extremely harmful to ocean and aquatic life.

The team of researchers, from the University of Basel and the Alfred-Wegener Institute (AWI) at the Helmholtz Centre for Polar and Marine Research, were studying water from the Weddell Sea.

Area where Endurance got trapped

It is the same area where, in 1915, Ernest Shackleton’s ship, Endurance, got trapped and crushed by pack ice.

Over the course of two expeditions with the research vessel Polastern during 2018 and 2019, the researchers took a total of 34 surface water samples and 79 subsurface water samples.

They then filtered about eight million litres of seawater and discovered microplastics in it – albeit in very small quantities.

Earlier studies of microplastics in Antarctica were conducted in regions with more research stations, shipping traffic and people, but this one solely focused on a remote body of water.

The research team, led by Professor Patricia Holm and Dr Gunnar Gerdts from the AWI, thought that the remote Weddell Sea would have substantially lower concentrations of microplastics.

Prof. Dr. Patricia Holm (left) and Clara Leistenschneider on the research vessel Polarstern - SWNS
Prof. Dr. Patricia Holm (left) and Clara Leistenschneider on the research vessel Polarstern – SWNS

However, their measurements showed that microplastic concentrations were only partially lower than in other regions in Antarctica.

Clara Leistenschneider, a doctoral candidate in the Department of Environmental Sciences, said: “Establishing that microplastics are present in a given region is one thing.

“But it’s also important to know which plastics appear, in order to identify their possible origin and in the best case to reduce microplastic emissions from these sources.”

In order to find out where these plastics came from, the team analysed the composition of the particles.

The team found that a significant proportion of the particles were in fact microplastics that were used as a binding agent in marine paint.

Other microplastic particles were identified as polyethylene, polypropylene and polyamides. These were used in packaging materials and fishing nets, among other things.

More than half of all the sample fragments were also visually similar to the ship paint on the vessel on which the team was travelling.


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Identifying paint fragments

At the Centre for Marine Environmental Sciences (Marum) at the University of Bremen, the researchers analysed these fragments in more detail, by X-raying fluorescence (XRF) to identify pigments and fillers.

They were analysed in forensics, along with their plastic content, in a process normally used to identify cars in hit and run-type accidents.

In a circumstance like this one, paint slivers left at the accident site are the same as a vehicle’s fingerprints.

The analysis showed that 89 per cent of the 101 microplastic particles that were studied in detail came from the Polastern.

The remaining 11 percent came from other sources.

Ms Lesitenschneider added: “Developing alternative marine paint that is more durable and environmentally friendly would make it possible to reduce this source of microplastics and the harmful substances they contain.”

The findings were published in the journal Environmental Sciences and Technology.

Source:

Will Bolton at Yahoo! News