Invasive species aren't necessarily the stuff of banners and headlines but for Antarctica, keeping them at bay is critical to keeping the continent pristine. For anyone who wonders why we make such a big deal about vacuuming bags, washing boots and not taking food ashore in Antarctica, here's why: http://www.livescience.com/13945-antarctica-invasive-species-food-transport.html
Antarctica Threatened by Invasion of Alien Species
Wynne Parry, LiveScience Senior Writer
29 April 2011
It's unforgivingly cold and isolated, but stowaways are arriving in Antarctica in a steady stream. Seeds, fungi and insects go where people -- in this case researchers and tourists -- take them. These arrivals all create the potential for invasive species to establish themselves in the world's most pristine continent and its islands.
"We are still at the stage when Antarctica has fewer than 10 non-native species, none of which have become invasive," said Kevin Hughes, an environmental scientist with the British Antarctic Survey. "Unless we take steps now to minimize the risk of introduction, who knows what will happen."
Invasive species are non-native species that flourish in a new habitat, where they often kick out native organisms and harm human interests by disrupting crops, clogging waterways and causing a myriad of other problems.
Hughes and other researchers have set out to determine just what is being carried unintentionally into some of the international research stations in the Antarctic. In one study, he and others examined more than 11,250 pieces of fresh produce arriving at nine research stations in the Antarctic and the sub-Antarctic islands located farther north in the Southern Ocean to see what came along with it.
The produce, which included everything from apples to pawpaw trees to turnips, was shipped from around the world. Its stowaways were similarly diverse, and included at least 56 invertebrates -- slugs, butterflies, aphids and so on. Twelve percent of the produce carried soil, and 28 percent had rot caused by microbial infection. [Taking a Bite Out of Invasive Species]
"Are these numbers surprising, or does it mean this is likely to be a problem? It’s pretty hard to say," said Daniel Simberloff, a professor at the University of Tennessee, Knoxville, who was not involved with the research. "The upshot is that there's just enough people going to some parts of Antarctica nowadays that lots of organisms are carried there. I have to think this isn't good, and some subset of them are going to pose environmental problems."
This study was part of a larger effort to assess what is actually arriving. In another project, Hughes and colleagues looked at dirt carried in by construction vehicles and found a menagerie of tiny non-natives that included about 40,000 seeds.
"To be quite honest, the only way we are going to stop the introduction of nonnative species is to stop going to Antarctica, to cut off all the pathways," Hughes said. "What we can do is try and minimize the risk of introduction and we can do that by relatively simple steps."
The study includes recommendations that begin with considering where the food comes from, all the way to how to dispose of food waste.
So far, alien species have made little headway on the continent itself. A rare, but limited success came for a tiny fly, the black fungus midge, which has managed to keep a toehold inside Casey Research Station, a British station located on mainland Antarctica. And Kentucky blue grass has also been established on the Antarctic Peninsula, Simberloff said.
The Antarctic islands have received more non-natives than the continent. For instance, another alien grass has been spreading on King George Island, which is just off the peninsula.
But further north, the sub-Antarctic islands have fared much worse, receiving approximately one new species every year since humans began visiting them 200 years ago, according to Hughes.
Invaders may get a helping hand from global warming, which is lessening the severity of the climate, possibly making conditions less harsh.
Saturday, April 30, 2011
Monday, April 11, 2011
Chinstrap Penguins suffering at the hands of global warming
We've been watching Adelie Penguin populations crash along the western Antarctic Peninsula, down something like 50 to 90% at the colonies I know the best. This is pretty clearly due to disappearing ice cover...... but now, apparently, Chinstrap Penguins are following the same course. I haven't seen this myself.... anyone have access to the original paper in Proceedings of the National Academy of Sciences to see where the documented Chinstrap decline is happening?
Not happy news. Thanks to Mary for brining this to my attention.
http://www.signonsandiego.com/news/2011/apr/11/penguin-decline-linked-warming-antarctic/
Penguin decline linked to warming in Antarctica
BY MIKE LEE ~ MONDAY, APRIL 11, 2011 AT 1:25 P.M.
Climate change appears to be harming a population of penguins that some researchers figured would benefit from warming temperatures, according to a new study by scientists at the National Marine Fisheries Service in La Jolla.
Instead of enjoying a reduction of sea ice, the ice-avoiding chinstrap penguins may be among the most vulnerable to temperature changes that threaten their staple food source, said a paper published online Monday in the peer-reviewed Proceedings of the National Academy of Sciences.
The findings may indicate more profound changes in the Antarctic ecosystem than previously thought. Antarctica is among the fastest-warming spots on the planet and a focus of studies by local researchers for decades.
One hypothesis about global warming is that it will create a variety of "winners" and "losers" in Antarctica. Under that scenario, ice-loving Adélie penguins would suffer but chinstrap penguins would benefit as the temperatures moderate and sea ice shrinks.
Adélie populations in the study area have fallen by an average of 2.9 percent per year for 10 years or more, while chinstrap numbers have decreased by even more -- an average of 4.3 percent per year over the same period, the study authors said.
“When we see steep declines in populations, as we have been documenting with both chinstrap and Adélie penguins, we know there’s a much larger ecological problem,” said Wayne Trivelpiece, the lead author of the study a seabird expert for the fisheries service.
“Penguins are excellent indicators of changes to the biological and environmental health of the broader ecosystem because they are easily accessible while breeding on land, yet they depend entirely on food resources from the sea," he said. "In addition, unlike many other krill-eating top predators in the Antarctic, such as whales and fur seals, they were not hunted by humans."
The La Jolla scientists link the shrinking penguin population to the decline of shrimp-like food source called krill, which penguins rely on heavily. Sea ice is a necessary part of the krill reproductive cycle and warming temperatures have undermined the population. The researchers said krill fishing also may play a role in krill numbers, which have plummeted by as much as 80 percent since the 1970s.
Adélie penguins are hampered by shrinking habitat and food shortages, but they have more breeding populations than chinstrap penquins and therefore researchers said they may not be as threatened by environmental changes.
"Long thought to be ecological winners in the climate-warming scenario, the chinstrap penguin instead may be among the most vulnerable species affected by a warming climate," the paper said.
Not happy news. Thanks to Mary for brining this to my attention.
http://www.signonsandiego.com/news/2011/apr/11/penguin-decline-linked-warming-antarctic/
Penguin decline linked to warming in Antarctica
BY MIKE LEE ~ MONDAY, APRIL 11, 2011 AT 1:25 P.M.
Climate change appears to be harming a population of penguins that some researchers figured would benefit from warming temperatures, according to a new study by scientists at the National Marine Fisheries Service in La Jolla.
Instead of enjoying a reduction of sea ice, the ice-avoiding chinstrap penguins may be among the most vulnerable to temperature changes that threaten their staple food source, said a paper published online Monday in the peer-reviewed Proceedings of the National Academy of Sciences.
The findings may indicate more profound changes in the Antarctic ecosystem than previously thought. Antarctica is among the fastest-warming spots on the planet and a focus of studies by local researchers for decades.
One hypothesis about global warming is that it will create a variety of "winners" and "losers" in Antarctica. Under that scenario, ice-loving Adélie penguins would suffer but chinstrap penguins would benefit as the temperatures moderate and sea ice shrinks.
Adélie populations in the study area have fallen by an average of 2.9 percent per year for 10 years or more, while chinstrap numbers have decreased by even more -- an average of 4.3 percent per year over the same period, the study authors said.
“When we see steep declines in populations, as we have been documenting with both chinstrap and Adélie penguins, we know there’s a much larger ecological problem,” said Wayne Trivelpiece, the lead author of the study a seabird expert for the fisheries service.
“Penguins are excellent indicators of changes to the biological and environmental health of the broader ecosystem because they are easily accessible while breeding on land, yet they depend entirely on food resources from the sea," he said. "In addition, unlike many other krill-eating top predators in the Antarctic, such as whales and fur seals, they were not hunted by humans."
The La Jolla scientists link the shrinking penguin population to the decline of shrimp-like food source called krill, which penguins rely on heavily. Sea ice is a necessary part of the krill reproductive cycle and warming temperatures have undermined the population. The researchers said krill fishing also may play a role in krill numbers, which have plummeted by as much as 80 percent since the 1970s.
Adélie penguins are hampered by shrinking habitat and food shortages, but they have more breeding populations than chinstrap penquins and therefore researchers said they may not be as threatened by environmental changes.
"Long thought to be ecological winners in the climate-warming scenario, the chinstrap penguin instead may be among the most vulnerable species affected by a warming climate," the paper said.
Thursday, April 7, 2011
South Georgia rat eradication phase I complete - and successful?
The first year of the hugely ambitious South Georgia Rat Eradication Programme has now been completed. After years of preparation and consultation, the first season of work, to clear four distinct areas of South Georgia of rats, has been achieved in only 26 days. Eight weeks had originally been allowed for 'Phase 1' to allow for the erratic weather conditions on the Island. Greene Peninsula, Thatcher Peninsula and Mercer Bay were baited first. The recently infested Saddle Island (on the North West of the Island) was the final area to be baited during this phase.
As for how effective the attempt to eradicate rats in these areas has been - the signs are good. There has been no evidence of live rats in the last few weeks and the team are optimistic the trial has been 100% successful.
For details on baiting and phase 2
Read the South Georgia Newsletter, March 2011
http://www.sgisland.gs/index.php/(h)South_Georgia_News_and_Events
As for how effective the attempt to eradicate rats in these areas has been - the signs are good. There has been no evidence of live rats in the last few weeks and the team are optimistic the trial has been 100% successful.
For details on baiting and phase 2
Read the South Georgia Newsletter, March 2011
http://www.sgisland.gs/index.php/(h)South_Georgia_News_and_Events
Wednesday, April 6, 2011
Penguin-guided robots invade Antarctica
Well, maybe 'invade' is the wrong word but it goes so well with 'robots'...
This is a nifty cool story, though sadly the research is motivated by that dramatic population crash we're seeing in Adelies on the western Antarctic Peninsula:
http://www.wired.com/wiredscience/2011/04/penguins-robot-surveys/
Swimming Penguins Guide Autonomous Underwater Robots
By Jane J. Lee ~ April 5, 2011
Autonomous robots that follow the routes of swimming penguins are collecting information that could help scientists understand why the birds’ populations are dropping rapidly.
The underwater robots, called gliders, are programmed to record ocean conditions as they follow the tracks of Adelie penguins swimming in the Southern Ocean surrounding Antarctica.
The penguins have been dying off in large numbers for decades, and scientists suspect that warming of the seawater could be to blame. Part of the problem may be disappearing sea ice, which grows algae that attracts the krill the birds prefer to eat.
“They’re probably starving to death,” said Bill Fraser, a penguin biologist and president of the Polar Oceans Research Group.
Adelie penguins spend hours, and even days, on feeding trips. But once they dive below the surface, it’s hard to know what the birds are dealing with. So Fraser and oceanographers Alex Kahl and Oscar Schofield, both of Rutgers University, turned to robots to find out what ocean conditions are like when Adelie penguins are in the water.
Fraser has been sticking radio tags on the penguins for a decade to keep track of where they go. But the equipment that could tell researchers whether there is krill or algae in the water with the penguins is still too big to put on a 9-to-10-pound bird.
Research ships have sampled areas over deep underwater canyons where Adelies hang out, but this only yielded snippets of what was going on. The gliders can provide a potentially continuous stream of information.
Schofield has been using gliders all over the world for years to gather data on ocean physics and chemistry to study plankton ecology.
Fraser and Schofield got together in 2008 to test whether they could program the gliders to collect information on the presence or absence of algae and krill in the the underwater canyons.
The gliders discovered blooms of microscopic algae, which krill eat. And because Adelies eat krill, this supported the scientists’ hypothesis that the penguins were feeding in these areas.
“With the radio tags on the penguins, we could see where they foraged and how deep they were,” said Schofield. But with the addition of the gliders, “for the first time, now we know why they’re there,” he said.
In subsequent studies, the researchers started using near real-time penguin-location data to direct the gliders. “We can get location data on the penguin in the evening and design a mission for the glider for the next day,” said Schofield.
In January, Schofield and Fraser used acoustic sensors on the glider to map the patches of krill that Adelies were eating.
“The concept of using animals to study oceanographic features isn’t new,” said Dan Costa, a marine-mammal and seabird researcher at the University of California–Santa Cruz, who wasn’t involved in the research. “But this is 9,000 times better than what we’ve been able to do” in the past.
The next step is to eliminate the middleman.
“My goal in five years is to have an automated network where you have penguins foraging, and my gliders are adjusting their tracks automatically,” said Schofield.
Citation: “Autonomous Gliders Reveal Features of the Water Column Associated With Foraging by Adelie Penguins.” By L. Alex Kahl, Oscar Schofield and William R. Fraser. Integrative and Comparative Biology, Vol. 50 August 2010.
This is a nifty cool story, though sadly the research is motivated by that dramatic population crash we're seeing in Adelies on the western Antarctic Peninsula:
http://www.wired.com/wiredscience/2011/04/penguins-robot-surveys/
Swimming Penguins Guide Autonomous Underwater Robots
By Jane J. Lee ~ April 5, 2011
Autonomous robots that follow the routes of swimming penguins are collecting information that could help scientists understand why the birds’ populations are dropping rapidly.
The underwater robots, called gliders, are programmed to record ocean conditions as they follow the tracks of Adelie penguins swimming in the Southern Ocean surrounding Antarctica.
The penguins have been dying off in large numbers for decades, and scientists suspect that warming of the seawater could be to blame. Part of the problem may be disappearing sea ice, which grows algae that attracts the krill the birds prefer to eat.
“They’re probably starving to death,” said Bill Fraser, a penguin biologist and president of the Polar Oceans Research Group.
Adelie penguins spend hours, and even days, on feeding trips. But once they dive below the surface, it’s hard to know what the birds are dealing with. So Fraser and oceanographers Alex Kahl and Oscar Schofield, both of Rutgers University, turned to robots to find out what ocean conditions are like when Adelie penguins are in the water.
Fraser has been sticking radio tags on the penguins for a decade to keep track of where they go. But the equipment that could tell researchers whether there is krill or algae in the water with the penguins is still too big to put on a 9-to-10-pound bird.
Research ships have sampled areas over deep underwater canyons where Adelies hang out, but this only yielded snippets of what was going on. The gliders can provide a potentially continuous stream of information.
Schofield has been using gliders all over the world for years to gather data on ocean physics and chemistry to study plankton ecology.
Fraser and Schofield got together in 2008 to test whether they could program the gliders to collect information on the presence or absence of algae and krill in the the underwater canyons.
The gliders discovered blooms of microscopic algae, which krill eat. And because Adelies eat krill, this supported the scientists’ hypothesis that the penguins were feeding in these areas.
“With the radio tags on the penguins, we could see where they foraged and how deep they were,” said Schofield. But with the addition of the gliders, “for the first time, now we know why they’re there,” he said.
In subsequent studies, the researchers started using near real-time penguin-location data to direct the gliders. “We can get location data on the penguin in the evening and design a mission for the glider for the next day,” said Schofield.
In January, Schofield and Fraser used acoustic sensors on the glider to map the patches of krill that Adelies were eating.
“The concept of using animals to study oceanographic features isn’t new,” said Dan Costa, a marine-mammal and seabird researcher at the University of California–Santa Cruz, who wasn’t involved in the research. “But this is 9,000 times better than what we’ve been able to do” in the past.
The next step is to eliminate the middleman.
“My goal in five years is to have an automated network where you have penguins foraging, and my gliders are adjusting their tracks automatically,” said Schofield.
Citation: “Autonomous Gliders Reveal Features of the Water Column Associated With Foraging by Adelie Penguins.” By L. Alex Kahl, Oscar Schofield and William R. Fraser. Integrative and Comparative Biology, Vol. 50 August 2010.
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