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Sunday, April 25, 2010

Happy World Penguin Day!


Each year, on or about the 25th of April, the Adelie penguins of Ross Island leave their brooding grounds and swim to their winter sanctuary northwest of the Balleny Islands. Some decided to mark the occasion by including all penguins and dubbing the day World Penguin Day.


Most penguins do participate in migratory habits. Why they favor some places more than others as their destination is the current  work of biologists. Current belief is that the Adelies favor a place that has more pack ice, thereby providing more protection.  This appears to be true, as the Davis Station Adelies migrate north, then west, staying close to the Antarctic continent. The Magellanic penguins of South America travel to Mar del Plata, where usually there is more food and less harsh conditions; however, in the past few years, the Magels have suffered many losses due to inadequate food. The Falkland Island Rockhopper Penguins have traditionally migrated to coastal South America, and the northernmost of the colonies favored the areas along the Patagonian Shelf.  The Macaronis stay in the sub-Antarctic area, mostly at sea, during their migration from their breeding grounds.


These are just a few instances of penguin migration; the point is that they do migrate and when they do, this action initiates the end of the breeding season and the beginning of a new life in the vast southern ocean for thousands of newly molted juveniles. Welcome to your world, little guys. Bon voyage!!!


wiinterrr



Image by Flickr/Benjamin Fox

Monday, April 19, 2010

A Satellite Census For Penguins

For Penguins, a Satellite Census

Biologists Count Hard-to-Find Birds With Photos Supplied by Intelligence Agency

[PENGUIN1] Minden
Emperor penguin colonies, like this one on Cape Roget, are widely spaced in Antarctica, making it difficult to conduct a census of the birds.

MCMURDO, Antarctica—Bird-watcher Philip Trathan is counting the emperor penguins here—from space.
In the first complete census of these well-known birds, the British wildlife ecologist and his colleagues are scanning high-resolution satellite photos of Antarctica for penguins, like military analysts searching for Iranian rocket sites. In fact, their precision imagery comes from the U.S. National Geospatial Intelligence Agency. The photos are part of the roughly $25 million of commercial satellite images the agency buys every month for use by the Central Intelligence Agency and the Defense Department.

Tracking Penguins in Antarctica from 400 Miles Up

3:32
Researchers are using satellite data to track penguins and seals across the coldest region on earth without disturbing them - and without leaving home. WSJ's Robert Lee Hotz reports.

"You can count individual birds," said Dr. Trathan, a penguin ecologist at the British Antarctic Survey, who is part of an international census team.

Their penguin census, which will be completed later this year, is the latest application of satellite mapping techniques that are transforming perceptions of Antarctica, where millions of square miles of ice blend into a wilderness of white, and only penguins are truly at home. In many ways, this shifting snowscape is as uncharted as the day explorers first sighted its mainland almost 200 years ago.

"Until last year, we had better maps of Mars than of Antarctica," said Paul Morin, director of the University of Minnesota's Antarctic Geospatial Information Center, which is funded by the U.S. National Science Foundation to use the unclassified intelligence imagery in science projects like the penguin survey. "We can now see one of the most inaccessible places on Earth, on demand," Mr. Morin said.

Landsat Image Mosaic of Antarctica, USGS, NASA
A Landsat image of Cape Washington in Antarctica shows a brownish smudge at center that is guano from large emperor penguins.
Landsat Image Mosaic of Antarctica, USGS, NASA
A Landsat image shows a guano stain at upper right from large emperor penguins in Antarctica.
With the newest high-resolution imagery, researchers can detect anything on the continent larger than an end table. At that scale, a four-foot-tall, 90-pound emperor penguin is just large enough to show up in a single pixel. Dressed by nature in darkly formal feather-wear, an emperor penguin stands out in high contrast against the ice, even when viewed by a camera moving at four miles a second in an orbit 423 miles overhead.

Still, the emperor penguins complicate the count by huddling together for warmth. On an especially cold day, as many as 10 of them can cram together on a square meter of ice—a space slightly larger than a single pixel. "If you have so many pixels of penguins," said mapping expert Peter Fretwell at the British Antarctic Survey, "you have to decide how many penguins per pixel." Wildlife biologists estimate the count will turn up between 200,000 and 400,000 breeding pairs.

Living across the continent's 5.4 million square miles of polar ice, the emperor penguins are a bellwether that can help researchers detect subtle changes in climate and ocean conditions affecting all of Antarctica. Other penguin species wax and wane in response to changing regional winds, temperature trends and commercial fishing. But so far, no one knows how emperor penguins have responded to the changes, because there has been no easy way to find them all.

"Emperors are a really tricky species to get a handle on," said Dr. Trathan. "At the moment, nobody really knows how threatened emperor penguins really are."
It's no wonder. The birds make themselves at home in two of Earth's most inaccessible environments. No other bird dives deeper underwater, as far as 1,500 feet. No other creature breeds on the sea ice during Antarctica's winter darkness, when temperatures drop to 80 degrees below zero and winds top 100 mph.

Penguins Under Pressure

Robert Lee Hotz/The Wall Street Journal
An international team of scientists is researching how Adélie penguins in Antarctica are coping with rapidly changing ice conditions and commercial fishing.
For years, field biologists based here at the U.S. McMurdo Station have tracked meandering emperors, bobbing like off-balance bowling pins, as they slip, slide and belly-flop over ridges of wind-rippled snow.
They have stood on stepladders to count the birds in congested formations, and hung cameras from helium-filled balloons to record their numbers more reliably.

They have bugged penguins with radio transmitters and shadowed them by jet with airborne infrared sensors that could detect a birds' body heat at a distance. Such techniques proved too intrusive and expensive for a systematic census.

The new census is not the first time penguin watchers have tried satellites. By chance, researchers last year discovered they could detect vast stains of penguin excrement on the ice using older low-resolution satellite images. That revealed the locations of 38 emperor colonies, 10 of them never seen before, Dr. Trathan and his colleagues reported last June in the journal Global Ecology and Biogeography.

Still, they couldn't actually see any penguins until they gained access to the newest images, which the intelligence agency buys from commercial satellite operators DigitalGlobe Inc. in Longmont, Colo., and GeoEye Inc. in Dulles, Va..

Scientists hope the newest images will allow them to study emperor penguins without disturbing them—and without leaving their home laboratories.

"If you can do it from space," said Dr. Trathan, "you can do it from your desk."

Write to Robert Lee Hotz at sciencejournal@wsj.com

Source 

New Paper on King Penguins

Original Paper

Do penguins dare to walk at night? Visual cues influence king penguin colony arrivals and departures
Anna P. NesterovaContact Information, Céline Le Bohec2, 3, David Beaune3, Emeline Pettex1, Yvon Le Maho3 and Francesco Bonadonna1
(1)  Behavioural Ecology Group, CEFE–CNRS, 1919 route de Mende, 34293 Montpellier, Cedex 5, France
(2)  Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway
(3)  Département d’Ecologie, Physiologie, et Ethologie, IPHC–CNRS, 23 rue Becquerel, 67087 Strasbourg, Cedex 2, France
Received: 15 June 2009  Revised: 8 February 2010  Accepted: 10 February 2010  Published online: 9 March 2010
Communicated by C. Brown
Abstract  
Orientation based on visual cues can be extremely difficult in crowded bird colonies due to the presence of many individuals. We studied king penguins (Aptenodytes patagonicus) that live in dense colonies and are constantly faced with such problems. Our aims were to describe adult penguin homing paths on land and to test whether visual cues are important for their orientation in the colony. We also tested the hypothesis that older penguins should be better able to cope with limited visual cues due to their greater experience. We collected and examined GPS paths of homing penguins. In addition, we analyzed 8 months of penguin arrivals to and departures from the colony using data from an automatic identification system. We found that birds rearing chicks did not minimize their traveling time on land and did not proceed to their young (located in crèches) along straight paths. Moreover, breeding birds' arrivals and departures were affected by the time of day and luminosity levels. Our data suggest that king penguins prefer to move in and out of the colony when visual cues are available. Still, they are capable of navigating even in complete darkness, and this ability seems to develop over the years, with older breeding birds more likely to move through the colony at nighttime luminosity levels. This study is the first step in unveiling the mysteries of king penguin orientation on land.
Keywords  Short-range navigation - King penguins - Seabirds - Visual landmarks - Nocturnal movements -  Aptenodytes patagonicus

Friday, April 16, 2010

Revised ASPA plan for Cape Hallett preserves huge Adélie colony

Kevin Pettway counts penguins.
Photo Credit: Jessie Jenkins
Kevin Pettway, the lead environmental specialist at Raytheon Polar Services Co., counts penguins on Seabee Hook to collect data for a revised Cape Hallett ASPA plan, as well as for ongoing Adélie research in Antarctica. Pettway's team conducted the most thorough assessment ever of an ASPA.

Added protection

Revised ASPA plan for Cape Hallett preserves huge Adélie colony

Kevin Pettway will be the first person to tell you it’s not easy to get to Cape Hallett. But he’ll also tell you the trip is well worth the effort to help protect one of Antarctica’s biological gems.
The journey required the support of a nearby Italian research station, Terra Nova, and a couple of extra nights stuck in a “bare bones” tent camp thanks to the continent’s unpredictable weather.
“Getting out to Hallett is very difficult because it is so far away [from McMurdo Station],” said Pettway, the lead environmental specialist at Raytheon Polar Services Co. (RPSC) External Non-U.S. government site.
Adelie penguin colony on Seabee Hook.
Photo Credit: Jessie Jenkins
The northern limit of the Adélie penguin colony.
Kevin Pettway tends to a scientific experiment.
Photo Credit: Jessie Jenkins
Kevin Pettway downloads data from a New Zealand Antarctica soil experiment.
“Having the Italian support was absolutely key to the success of this project,” he added, explaining that the crew at Terra Nova, located about halfway between McMurdo and Cape Hallett, helped move people and cargo by helicopter to the cape, a spit of land surrounded by sea ice eight months of the year.
Site of a former joint U.S. and New Zealand research station, Cape Hallett is home to a huge colony of Adélie penguins, and a diverse range of lichens, moss and tiny invertebrates. It’s also become a new model for how the U.S. Antarctic Program (USAP) External U.S. government site would like to approach conservation of Antarctic resources in the future.
Cape Hallett first gained special protection under the Antarctic Treaty External Non-U.S. government site system in 1966 at the request of the United States. Following the 1998 implementation of a comprehensive plan called the Protocol on Environmental Protection to the Antarctic Treaty, Cape Hallett became an Antarctic Specially Protected Area (ASPA) External Non-U.S. government site. Each ASPA is associated with a plan designed to manage access and to minimize impacts to the environment.
Pettway and his three-person team spent a week at Cape Hallett to redefine the ASPA boundaries and to survey the various animal populations. The USAP plans to submit a revised ASPA plan for Cape Hallett at the next meeting of the member nations to the Antarctic Treaty in Uruguay later this year.
“We probably did the most thorough site assessment of an ASPA that’s been done,” said Nate Biletnikoff, manager of RPSC’s environmental engineering department. RPSC provides much of the logistical support for the USAP, which is managed by the National Science Foundation (NSF) External U.S. government site.
Seabee Hook at Cape Hallett
Photo Credit: Kevin Pettway
Seabee hook at Cape Hallett.
RPSC hired a subcontractor, Environmental Research & Assessment (ERA) External Non-U.S. government site, which specializes in creating management plans in polar environments, to help develop the ASPA plan. Two ERA members, Colin Harris and Rachel Carr, used high-precision GPS technology from Boulder, Colo.-based UNAVCO External Non-U.S. government site to map the boundaries of the penguin colony, which boasts about 64,000 breeding pairs.
“We basically surveyed the entire area,” Biletnikoff said. “This is first time we’ve ever surveyed the spatial extent of a penguin colony to this level of detail.”
Tourism is partly the reason behind the detailed survey, according to Biletnikoff. The International Association of Antarctic Tour Operators External Non-U.S. government site said 322 tourists visited Cape Hallett during the 2008-09 season.
Helicopter and crew with the Italian Antarctic program.
Photo Credit: Jessie Jenkins
The Italian Antarctic program assisted the USAP environmental team with helicopter support.
“It is of high value to Antarctic tour operators in the Ross Sea region because of its high aesthetic values and accessibility,” Biletnikoff said.
While environmental protection has long been a fixture in the management of Antarctica, people have not always treaded so lightly on the continent. The original establishment of Cape Hallett Station on a site dubbed Seabee Hook in 1956 involved the “eviction” of more than 7,500 penguins, including some 3,300 chicks, to clear space for construction.
The colony declined from 62,900 pairs in 1959 to a low of 37,000 pairs in 1968. It has since recovered its former numbers and has started to re-occupy the site of the station, which ceased operations in 1973. The area itself has been cleaned up, and the last structures removed by the Italians in January 2010. Many of the historical artifacts from the station are located at the Canterbury Museum External Non-U.S. government site in Christchurch, New Zealand.
“The colony just keeps creeping forward. [ERA is] anticipating that the colony will fill into the coastline for the most part,” Biletnikoff said.
The new site map for tourist access proposes additional landing sites for boats, he said, to help minimize disturbances to the colony by ensuring operators come ashore at recognizable landmarks.

By the Numbers
Square kilometers of updated Cape Hallett ASPA: 0.53 square kilometers
Adélie penguins: 64,000 breeding pairs
South polar skuas: About 232 birds and 250 numbered nests
Other wildlife in the region: Emperor penguins, chinstrap penguins, Wilson’s storm petrels, snow petrels, southern giant petrels, Weddell seals, leopard seals and minke whales.
Number of invertebrates: Eight species of mites and three species of springtails
Vegetation: Five species of moss and 18 lichens
Total ASPA sites: 71
Number of ASPA sites under U.S. management: 13

The ASPA plan also includes a smaller restricted area that has been the site of a comparative study of flora since the 1960s. The site contains five different moss and 18 kinds of lichens. Pettway said the team found the stakes that defined the boundary and then built rock cairns to better delineate the area so visitors would not accidently disturb the sensitive vegetation.
“That was difficult — figuring out where it was and moving the rocks without disturbing the moss and lichens,” he said.
The environmental team also played scientist on behalf of several researchers who have interests in the ecosystem. For instance, they counted penguins and eggs for David Ainley External Non-U.S. government site, a principal investigator on a long-term study of the tuxedoed seabirds around the Ross Sea.
“It was a lot harder to count penguins than you would think,” said Pettway, who, along with Jessie Jenkins, field center supervisor, spent most of the week tallying penguins, skuas and seals.
He also repaired an automatic weather station for the University of Wisconsin-Madison External Non-U.S. government site and downloaded data for Antarctica New Zealand External Non-U.S. government site from a long-term soil experiment that is part of the Latitudinal Gradient Project External Non-U.S. government site.
“It goes beyond the ASPA management plan. We helped Ainley out. We helped Antarctica New Zealand out. … There are a lot of other things that we did out there,” Biletnikoff noted.

Source

Thursday, April 1, 2010