Tuesday, May 17, 2011

Penguins manage muscle oxygen supplies while diving

Penguins are clever creatures --- turns out they adjust their oxygen consumption based on how they are diving. Great stuff!

Penguins' Oxygen Trick: How They Survive Deep Dives
Jennifer Welsh, LiveScience Staff Writer ~ 12 May 2011
http://www.livescience.com/14117-penguin-diving-feat-oxygen-trick.html

And a very nifty graphic:
http://www.livescience.com/14125-deepest-divers-emperor-penguins-ocean-life.html

Penguins are the acrobatic athletes of the seas, and they can keep diving for long periods of time because they have exquisite control over how and when their muscles use oxygen, new research indicates.

The penguins can switch between two modes of oxygen use — either starving their muscles or giving them an extra shot of oxygen to keep them working — to achieve their amazing dives.

"It appears that there's a little bit of plasticity or variability in what they do when they are diving," said study researcher Cassondra Williams of the University of California in San Diego. "It's much more complicated than we thought."

To figure out how penguins survive deep dives on a single breath of air, the researchers designed special probes to monitor the levels of oxygen in the penguins' muscles during their dives off McMurdo Sound, Antarctica. The results are based on three emperor penguins and 50 dives, which ranged from 23 to 210 feet (7 to 64 meters) in depth, which lasted from 2.3 to 11.4 minutes.

"They have two different patterns they can opt for while they are diving," Williams told LiveScience. "In one, they appear to cut off blood flow completely to the muscle, leaving it to rely on its own supplies, which leaves the blood oxygen for the rest of the body, like the brain and the heart."

In other dives, the researchers saw a plateau after the initial oxygen drop. They believe that the penguin is selectively sending extra oxygen from the blood into the muscles, so they don't get tired. They can only do this for a limited time, though, until blood oxygen levels become too low for the rest of the body. Eventually the penguins need to come up for air.

Cutting off the oxygen supply to the muscles forces them to start making energy using "anaerobic" respiration, which is done without oxygen. It has a downfall, though; it produces abyproduct called lactic acid that can be toxic in high doses.

If the penguins let the lactic acid accumulate in their muscles, it takes longer to recuperate after a long dive, the researchers believe. This may be why on some dives the penguins send extra oxygen. For example, an extra oxygen shot might be beneficial if the penguins are taking several dives during a short stint to, say, chase down a school of fish and don't want to lose the feeding opportunity while they spend additional time on the ice recuperating.

"They don't want to hit their aerobic limit and accumulate lactic acid, but it's not clear how or why they do that," Williams said.

The study was published May 12 in the Journal of Experimental Biology.

Monday, May 9, 2011

Whale wars in the courts and on the Seas --- Australia is suing Japan over Antarctic Whaling

Australia is upping the ante here; with the recent 'failed' Antarctic whaling season that Japan ended early due to Sea Shepherd's efforts, plus legal action against them, it hasn't looked better to be a cetacean since humans started using tools.

Australia Takes Case To Stop Japan Whaling To International Court
http://www.nasdaq.com/aspx/stock-market-news-story.aspx?storyid=201105082137dowjonesdjonline000099&title=australia-takes-case-to-stop-japan-whaling-to-international-court

SYDNEY - Australia's government Monday will lodge a written submission at the International Court of Justice calling for an end to Japan's whaling program in the Antarctic ocean and setting the Pacific allies up for a prolonged legal spat.

Japan says it engages in whaling for scientific research and rejects Canberra's charges that the country is breaching the International Convention for the Regulation of Whaling and a ban on whaling inthe Southern Ocean Sanctuary.

Legal action between the two countries became a reality in 2010 after years of agitation failed to win a breakthrough, prompting Australia's then Prime Minister Kevin Rudd to opt for the Hague-based ICJ in an effort to end Japan's Southern Ocean whaling program and win support for a global ban on whaling.

"Despite Australia repeatedly calling on Japan to cease its illegal whaling activities, Japan has refused to do so. That is why the Australian Government has taken this case in the ICJ," the Australian government said in a statement.

The Antarctic Ocean, also known as the Southern Ocean, stretches from the continent of Antarctica in the south but does not have a clearly defined northern limit.

Killed for their oils, five whale species in Australian waters are listed for protection by the government, including the humpback and blue whales.

Australia has been monitoring Japan's activity in the waters in recent years and there have been frequent clashes between anti-whaling protesters such as the Sea Shepherd Conservation Society and Japanese whaling boats.

Australia's submission will not be publicly released until the International Court of Justice decides on it. Japan has until March 2012 to respond. "The Government believes the whaling carried out by Japan is commercial, not scientific, and does not fall within that narrow exception," the Australian statement said.

-By Enda Curran, Dow Jones Newswires; 61-2-8272-4687; enda.curran@dowjones.com

Saturday, April 30, 2011

This is why we wash our boots when going to Antarctica

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.

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.

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

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.

Saturday, March 26, 2011

Whaling is finished?

I've wondered what impact the tsunami had on the Japanese whaling fleet. No word on if the government fleet that operates in Antarctica sustained any damage, but Ayukawahama, one of four communities from which coastal whaling is based, suffered heavy damage.


Japanese Town Mulls Future Without Whaling Industry ~ By MARTIN FACKLER
http://www.nytimes.com/2011/03/25/world/asia/25whale.html?_r=1&partner=rss&emc=rss&pagewanted=all
Published: March 24, 2011 ~ The New York Times


AYUKAWAHAMA, Japan — At first glance, it seemed like just one more flattened building in a seaside town where a tsunami had leveled hundreds of homes. But survivors gathered at this one to stand and brood.

Ayukawahama was close to the epicenter of Japan’s quake.
They came to what had been the headquarters of Ayukawa Whaling, one of only a handful of companies left in Japan that still hunted large whales. Those who gathered on a chilly recent Thursday spoke as if the company’s destruction two weeks ago had robbed the town of its soul.

“There is no Ayukawa without whaling,” said Hiroyuki Akimoto, 27, a fisherman and an occasional crewman on the whaling boats, referring to the town by its popular shorthand.

Japan’s tsunami seems to have succeeded — where years of boycotts, protests and high-seas chases by Western environmentalists had failed — in knocking out a pillar of the nation’s whaling industry. Ayukawahama was one of only four communities in Japan that defiantly carried on whaling and eating whales as a part of the local culture, even as the rest of the nation lost interest in whale meat.

So central is whaling to the local identity that many here see the fate of the town and the industry as inextricably linked.

“This could be the final blow to whaling here,” said Makoto Takeda, a 70-year-old retired whaler. “So goes whaling, so goes the town.”

The damage was particularly heavy here because Ayukawahama sits on the tip of a peninsula that was the closest land to the huge undersea earthquake 13 days ago. The resulting tsunami tore through the tiny fishing towns on the mountainous coastline, reducing Ayukawahama to an expanse of splintered wood and twisted cars. Three out of four homes were destroyed, forcing half of the town’s 1,400 residents into makeshift shelters.

At the offices of Ayukawa Whaling, only a light green harpoon gun — which once proudly decorated the entrance — and an uprooted pine tree were left standing. Across a parking lot stood the skeletal frame of the factory where whale meat was processed. A beached fishing boat and crumpled fire truck lay on the raised platform where the whales were hoisted ashore to be butchered.

The company’s three boats, which had been sucked out to sea, washed up miles down the coast with remarkably little damage. But they remain grounded there.

Ayukawa Whaling’s chairman, Minoru Ito, said he was in the office when the earthquake struck, shattering windows and toppling furniture. He led the employees to higher ground.

All 28 of them survived, he said, though he later had to lay them off. He said he fully intended to rebuild, hopefully in time for an autumn hunt off the northern island of Hokkaido, though he acknowledged the recovery might take more time. He said the most costly part would be getting the whaling ships back in the water, an undertaking that the company cannot afford without government help.

Once the ships are ready, he wants to hire back the employees. However, he admitted that the waves might have scared some employees away, from both whaling and Ayukawahama.

“If we can fix the ships, then we’re back in business,” said Mr. Ito, 74, whose father was also a whaler. “They should not be afraid, because another tsunami like that won’t come for another 100 years.”

Other residents were similarly undaunted. Mr. Akimoto, the occasional whaler, who came with a friend to see the ruined company, said the town needed to resume whaling as soon as possible to lift its spirits.

He said the year would be a sad one because the town would miss the April hunting season, during which coastal whalers like Ayukawa Whaling are allowed to take 50 minke whales under Japan’s controversial whaling program, which is ostensibly for research.

Ayukawahama and the other three whaling communities — among them Taiji, made infamous by the movie “The Cove” — hunt only in coastal waters. Japan’s better-known whaling in the Antarctic is conducted by the government.

Mr. Akimoto said April was usually the town’s most festive month, especially when large whales were brought ashore. He said he would miss that feeling this year.

Added his friend, Tatsuya Sato, 20, “We are so hungry that if they brought a whale ashore now, the whole town would rush down to eat it.”

Many older residents compared the food shortages created by the tsunami with the hard-tack years after World War II, when Japan’s whaling industry boomed as a provider of scarce protein.

Those were the glory days of Ayukawahama, when the population swelled to more than 10,000 and whaling crews swaggered down streets that bustled with crowds drawn by cabarets and movie theaters. Today, Ayukawahama plays up its whaling history for tourists. Smiling cartoon whales adorn shop fronts and even manhole covers. The town also built its own whaling museum, which was gutted by the tsunami.

While no one expects a return to Ayukawahama’s postwar golden era, some wistfully hoped that whale meat could once more come to the rescue.

Seiko Taira said that food shortages here were particularly acute because the tsunami washed out roads, cutting off Ayukawahama for several days. She said she had neglected to store her own food, and was reduced to feeding her four children and one grandchild a single cup of instant ramen noodles and a few pieces of bread per day.

Ms. Taira, 54, said she had grown so desperate that she scavenged the tsunami wreckage for food. On Thursday, picking through the debris near the site of Ayukawa Whaling’s office, her 17-year-old daughter, Yumi, found a can of whale meat. She proudly held up the prize to her mother.

“I wish we could eat whale meat every day,” said Ms. Taira, who worked as caregiver for the elderly before the wave hit. “But the whalers are so old, I think they’ll just quit or retire after what happened.

“I think whaling is dead here,” she added.

Shin Okada, an official in the disaster-response office, said the town had its hands full bringing in more food and finding shelter for the homeless. He said officials had not had time to think about steps to revive the fishing and whaling industries.

On a plaza in front of the whaling museum, Shinobu Ankai struggled to remove the wheels from his overturned car, which had been deposited there by the tsunami. He did not want them to be stolen by the same people who drained the gas tank.

Like many older men in town, he is a retired whaler, and he spoke of hunts that once ranged from Alaska to the Antarctic. However, he said, whaling was in a terminal decline even before the tsunami.

“There was Sea Shepherd, and now this,” he said, referring to the American environmental group, which has sought to block Japan’s whaling in the Antarctic. “Whaling is finished.”