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Saturday, February 28, 2009
Penguinologist Dyan deNapoli Views Endangered Penguins
Dyan deNapoli visits Antarctica to view endangered penguins
By Sally Applegate / correspondent
Fri Feb 27, 2009, 12:18 PM EST
Georgetown -
Penguins — the appealing flightless birds are so popular in our culture they regularly star in movies and cartoons. Unfortunately their future is far from certain as global warming disrupts their habitat. Penguin expert Dyan deNapoli of Georgetown knows that too well.
deNapoli has just returned from Antarctica after serving as the onboard penguin authority on the ship Antarctic Dream. For the trip, she acted as a guest lecturer and penguin expert.
“The PR person for Antarctic Shipping S.A. in Chile looked up penguin experts and found that the whole first page on the Internet was me,” says deNapoli. “After reading that, Adam York called me in April and asked if I’d like to exchange my expertise for a free 11-day trip to Antarctica. I asked if my husband Marc could come with me and they agreed. I accepted right away.”
The lure of the trip for deNapoli was as much about making people aware of the environmental threat to penguin populations as it was actually seeing the Antarctic peninsula in person. She spent nine years as a senior penguin aquarist at the New England Aquarium in Boston, where she found the penguins to be smart, curious and affectionate, each with its own distinctive personality.
She is currently writing a book on her experiences serving as a rehabilitation manager during the massive international rescue effort that saved 91 percent of the 20,000 penguins covered with oil when the iron ore ship MV Treasure sank near their South African breeding grounds.
She has received extremely generous advance offers from publishers for the rights to her upcoming book on the historic and heroic wildlife rescue in the year 2000. It was the largest number of a single species ever to be rescued and rehabilitated.
Years of field experience with penguins led to an invitation for her to write a new penguin entry for the New Book of Knowledge encyclopedia, the oldest encyclopedia in the United States, according to deNapoli.
“They wanted a completely new chapter on penguins, since theirs had not been updated for 40 years,” says deNapoli. “I just wrote this from scratch, keeping it within the style of the rest of the encyclopedia. They said they were thrilled with it. It came out in 2008.”
The boat to Antarctica
Getting to and from Antarctica by boat is a real challenge, as the route goes through Cape Horn and the Drake Passage at the southern tip of South America, the stormiest patch of ocean on the planet. Cape Horn is notorious for huge waves as high as 55-feet, gale force winds and icebergs. Numerous ships were lost there before the Panama Canal was built in 1914.
The boat — carrying deNapoli, her husband, 43 crew and about 69 passengers — encountered five- to eight-foot waves going down, and nine- to 15-foot waves coming back.
“When we first came on board and entered the dining room, we saw all the chairs were chained to the floor,” says deNapoli. “The Antarctic Dream is a former naval vessel, without a stabilizer, so there is a lot of pitching from side to side. A lot of the passengers were seasick. You worked all day to keep your balance. Trying to take a shower you tried not to fall down. In the dining room the waiters were amazing, carrying these heavy trays. At every meal you’d hear trays crashing in the kitchen.
“The weather can change in a heartbeat. As we were leaving Antarctica on our last day, within a 45-minute period we encountered sideways snow, driving rain, sunshine, flat seas, and eight-foot seas.”
Since it is now summer in Antarctica, the sun never set, and deNapoli says as a result she never felt tired and she and her husband took pictures almost around the clock the first day.
“You are in a stunningly beautiful area, and you always get to enjoy it [in daylight],” says deNapoli.
The trip takes two-and-a-half days each way. The Antarctic Dream is relatively small and could get into bays some of the larger vessels can’t enter.
“We made two landings a day in Zodiacs, and there were plenty of penguins, mostly Gentoo with some Chinstrap,” says deNapoli. “Because the chicks were still small, the adults were calm about our presence, but less likely to come up to us than when it isn’t breeding season. We saw penguins, penguins, and more penguins — doing breeding displays, and with chicks or eggs. We got to see the trade-off of the egg when one parent came back from feeding in the sea. It was very cool. It’s a photographer’s paradise.”
On the final day, passengers got a chance to swim at Deception Bay, where heat vents from a volcano create warm water.
“It wasn’t swimming actually, they only dug us an eight-inch-deep hole, so we were more like wallowing,” says deNapoli. “We jumped into the 30 degree ocean water then ran across the sand to the warm water. We each got a certificate that says, ‘I swam in Antarctica.’”
Penguins in peril
Global warming is now threatening all 17 species of penguins on the planet, and at an alarming rate, according to penguin expert Dyan deNapoli of Georgetown. Rising water temperatures are causing the fish, squid and krill penguins depend on to move further away to find colder waters and currents. They often move out of the Antarctic and sub-Antarctic penguins’ hunting range, leading to starvation of adults and chicks, and sometimes stopping them from breeding altogether.
Sea ice in Antarctica is steadily decreasing, removing the breeding grounds for the krill that the penguins eat and decreasing their food supply. Warming temperatures in Antarctica are causing large sections of ice shelf to break free from the continent, one as large as Rhode Island and one seven times the size of Manhattan. These huge floating ice chunks sometimes block access to breeding grounds the penguins have used for thousands of years, and they are abandoning them.
Increasing snowfall caused by global warming is burying penguin nests, and when the snow melts, the nests fill with water, drowning the eggs or chicks. Many penguins are abandoning their colonies and moving further south in search of colder temperatures. The Emperor penguins made famous in the film “March of the Penguins” are losing the ice shelves where they breed and raise their chicks 70 miles inland from the sea. DeNapoli says chicks whose waterproof feathers are not in place by the time the ice shelf melts back to where they are being raised are already drowning as a result.
You can learn more about penguins and global warming at www.AllExperts.com in a section written by deNapoli. She intends to donate a significant portion of the proceeds from her upcoming book on the historic penguin rescue in Africa to the organizations listed at her Web site
Images and story courtesy of Wicked Local Georgetown @
http://www.wickedlocal.com/georgetown/news/x1959827647/Dyan-deNapoli-visits-Antarctica-to-view-endangered-penguins
Friday, February 27, 2009
Macaroni penguin (Eudyptes chrysolophus)
Macaroni penguin (Eudyptes chrysolophus)
Facts
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Eudyptes (1)
Size Length: 71 cm (2)
Average weight: 5.5 kg (3)
Status
Classified as Vulnerable (VU A1b) on the IUCN Red List 2003 (1).
Description
This large, crested penguin is similar in appearance to other members of the genus Eudyptes; the macaroni penguin is, however, larger than all other species except the royal penguin (E. schlegeli) (4). Adult macaroni penguins have golden-yellow plume-like feathers that arise from a central patch on the forehead, extending back along the crown and drooping down behind the eye (4) (2). The head, chin, throat and upperparts are black; the underparts are white and the flippers are black on the uppersurface but mainly white below (4). The large bill is orange-brown; the eyes are red and there is a patch of bare pink skin from the base of the bill to the eye. The legs and feet are pink. Males and females are similar in appearance, but males tend to be slightly larger (4). Immature birds lack the head plumes or have a few sparse yellow feathers on the forehead; their bills are smaller than those of adults and are brownish-black in colour; the chin and throat are dark grey (4).
Range
The macaroni penguin has a circumpolar range (4). It breeds at 50 known sites on sub-Antarctic islands in the South Atlantic and southern Indian Oceans, with one breeding site on the Antarctic Peninsula (2) (4). Main breeding populations are located on the islands of Crozet, Heard, McDonald, Keruguelen and South Georgia (2). In 12 years, study populations on South Georgia have decreased by 65% and it is thought that the overall population on South Georgia has declined by 50% in the last 20 years (2). Most of the world population of this penguin has declined by at least 20% in the last 36 years (equivalent to three generations), but surveys are required to confirm the status of the species (2). The range of the macaroni penguin outside of the breeding season is unknown, although it is thought that it stays in Antarctic waters (4).
Habitat
Breeding colonies are situated on rocky slopes or level ground, usually in areas lacking vegetation, although some nests are located amongst tussock grass (4). Little is known of this species outside of the breeding season, but it is believed that it is pelagic, spending all of its time at sea (4).
Biology
The macaroni penguin is mainly active during the day. Very little is known of the species outside of the breeding season; most studies have been carried out on breeding birds. They feed mainly on krill (shrimp-like crustaceans), although in some areas, fish become an increasingly important food source as the breeding season progresses (5). It has been estimated that macaroni penguins alone consume four million tonnes of krill each year (6). In some populations, dives typically take the form of a V-shape, reaching depths of 48 m (4), although in other populations, the dive profiles were more complex (5).
Birds return to the breeding colonies each year in October and November, with males arriving before the females (4). Individuals often have to walk hundreds of meters over screes to reach their nest site (2). Macaroni penguins are monogamous and pair-bonds are long-lasting. Each year the pair reunites at the same nest location, recognising each other by means of their calls (4). Pairs often perform a display known as the ‘ecstatic display' in which their heads are swung from side to side (4). The nest is a simple scrape in the ground, typically lined with small rocks. In some cases, it may be made on a patch of grass and lined with grass shoots (4). Two eggs are laid; the second egg is always larger than the first and is usually the only successful egg per nest. If both eggs are lost, the pair is unable to produce a replacement brood (3).
Incubation takes up to 37 days and is shared by the parents in three main shifts. The first shift lasts for 8 - 12 days and is shared by the male and female. The second shift (12 - 14 days) is carried out by the female and the final shift (9 - 11 days) by the male. During each shift, the non-incubating bird goes to forage at sea during the day (4) (2). The newly hatched chicks are helpless, and for the first 23 - 25 days they are guarded and brooded by the male, while the female forages and feeds the chicks each day by regurgitating food (4). After this period, the chicks have developed their first plumage, which allows them to maintain their own temperature and so they can leave the nest. They cluster into small crèches for protection; at this stage, both parents are able to forage (3). Most chicks will have fledged at 60 - 70 days of age (4), at which point they have developed waterproof plumage (3). They do not start to breed until five years of age in females and six in males (4).
After the chicks leave the breeding colonies, the adults feed at sea for around three weeks before their annual moult. During the moult they are unable to forage, as their plumage is not watertight. After the 25-day moult the adults leave the colonies to spend the winter at sea (3).
In undisturbed colonies, predation is relatively low. Eggs (mainly deserted ones) are predated upon by skuas, sheathbills, and kelp gulls while weakened chicks, or those separated from the crèche are taken by skuas and giant petrels. Whilst at sea, adult macaroni penguins are predated upon by leopard seals and Antarctic fur seals (4).
Threats
Many penguin species of the Southern Oceans Ecosystem share a common set of factors that are causing population reductions (6) (2). Introduced predators such as cats and rats are a great problem for breeding birds on a number of islands, including South Georgia. Over-fishing is a very serious factor, in particular the harvesting of krill, the main food source of the macaroni penguin. Further pressures include oil spills and increasing tourism, as well as potential climate change, particularly as penguins are extremely sensitive to changes in sea temperature and ocean currents and the consequent decrease in prey availability (6).
Conservation
Although numbers of macaroni penguins are high, the decline of the overall population in the last 30 years have resulted in the classification of the species as globally Vulnerable by the IUCN Red List of Threatened Species (1). Long-term monitoring programmes are underway at a number of breeding colonies and many of the islands that support breeding populations of this penguin are protected reserves (2). The islands of Heard and McDonald are World Heritage Sites (2). If the suite of threats facing the macaroni penguin continue unabated, it seems likely that the population declines will continue.
Further Information
BirdLife International 2003 BirdLife's online World Bird Database: the site for bird conservation Version 2.0. Cambridge, UK: BirdLife International. (March 2004):
http://www.birdlife.org/
International Penguin Conservation Website (March 2004):
http://www.penguins.cl/macaroni-penguins.htm
Williams, T.D. (Ed.) (1995) Bird Families of the World – The Penguins. Oxford University Press, Oxford.
References
1. IUCN Red List of Threatened Species 2003 (March, 2004)
http://www.redlist.org
2. BirdLife International 2003 BirdLife's online World Bird Database: the site for bird conservation Version 2.0. Cambridge, UK: BirdLife International. (March, 2004)http://www.birdlife.org/
3. International Penguin Conservation Website (March, 2004)
http://www.penguins.cl/macaroni-penguins.htm
4. Williams, T.D. (1995) Bird Families of the World – The Penguins. Oxford University Press, Oxford.
5. Green, M.G., Williams, R. and Green, K. (1998) Foraging ecology and diving behaviour of macaroni penguins Eudyptes chrysolophus at Heard Island. Marine Ornithology, 26: 27 - 34.
6. Stokes, D.L. and Boersma, P.D. (1995) Conservation: threats to penguin populations. In: Williams, T.D. Ed. Bird Families of the World – The Penguins. Oxford University Press, Oxford.
Images and Information courtesy of ARKive @
http://www.arkive.org/macaroni-penguin/eudyptes-chrysolophus/info.html
What Agent in Prehistoric Global Cooling Caused Glaciers to Form at South Pole?
Prehistoric Global Cooling Caused by CO2 Declines, Research Finds
Ice in Antarctica suddenly appeared — in geologic terms — about 35 million years ago. For the previous 100 million years the continent had been essentially ice-free.
The question for science has been, why? What triggered glaciers to form at the South Pole?
Matthew Huber, assistant professor of earth and atmospheric sciences at Purdue University, says no evidence of global cooling during the period had been found.
“Previous evidence points paradoxically to a stable climate at the same time this event, one of the biggest climate events in Earth’s history, was happening,” Huber says.
However, in a paper published this week in the journal Science, a team of researchers found evidence of widespread cooling. Additional computer modeling of the cooling suggests that the cooling was caused by a reduction of greenhouse gases in the atmosphere.
Even after the continent of Antarctica had drifted to near its present location, its climate was subtropical. Then, 35.5 million years ago, ice formed on Antarctica in about 100,000 years, which is an “overnight” shift in geological terms.
“Our studies show that just over thirty-five million years ago, ‘poof,’ there was an ice sheet where there had been subtropical temperatures before,” Huber says. “Until now we haven’t had much scientific information about what happened.”
Before the cooling occurred at the end of the Eocene epoch, the Earth was warm and wet, and even the north and south poles experienced subtropical climates. The dinosaurs were long gone from the planet, but there were mammals and many reptiles and amphibians. Then, as the scientists say, poof, this warm wet world, which had existed for millions of years, dramatically changed. Temperatures fell dramatically, many species of mammals as well as most reptiles and amphibians became extinct, and Antarctica was covered in ice and sea levels fell.
History records this as the beginning of the Oligocene epoch, but the cause of the cooling has been the subject of scientific discussion and debate for many years.
The research team found before the event ocean surface temperatures near present-day Antarctica averaged 77 degrees Fahrenheit (25 degrees Celsius).
Mark Pagani, professor of geology and geophysics at Yale University, says the research found that air and ocean surface temperatures dropped as much as 18 degrees Fahrenheit during the transition.
“Previous reconstructions gave no evidence of high-latitude cooling,” Pagani says. “Our data demonstrate a clear temperature drop in both hemispheres during this time.”
The research team determined the temperatures of the Earth millions of years ago by using temperature “proxies,” or clues. In this case, the geologic detectives looked for the presence of biochemical molecules, which were present in plankton that only lived at certain temperatures. The researchers looked for the temperature proxies in seabed cores collected by drilling in deep-ocean sediments and crusts from around the world.
“Before this work we knew little about the climate during the time when this ice sheet was forming,” Huber says.
Once the team identified the global cooling, the next step was to find what caused it.
To find the result, Huber used modern climate modeling tools to look at the prehistoric climate. The models were run on a cluster-type supercomputer on Purdue’s campus.
“That’s what climate models are good for. They can give you plausible reasons for such an event,” Huber says. “We found that the likely culprit was a major drop in greenhouse gases in the atmosphere, especially CO2. From the temperature data and existing proxy records indicating a sharp drop in CO2 near the Eocene-Oligocene boundary, we are establishing a link between the sea surface temperatures and the glaciation of Antarctica.”
Huber says the modeling required an unusually large computing effort. Staff at Information Technology at Purdue assisted in the computing runs.
“My simulations produced 50 terabytes of data, which is about the amount of data you could store in 100 desktop computers. This represented 8,000 years of climate simulation,” Huber says.
The computation required nearly 2 million computing hours over two years on Pete, Purdue’s 664-CPU Linux cluster.
“This required running these simulations for a long time, which would not have been allowed at a national supercomputing center,” Huber says. “Fortunately, we had the resources here on campus, and I was able to use Purdue’s Pete to do the simulation.”
Additional members of the research team included David Zinniker at Yale; Robert DeConto and Mark Leckie at the University of Massachusetts, Amherst; Henk Brinkhuis at Utrecht University (Netherlands); and Sunita R. Shah and Ann Pearson at Harvard University. Zhonghui Liu, an assistant professor at the University of Hong Kong and a former postdoctoral fellow of Pagani’s at Yale, was the study’s lead author.
Photo of Neko Harbour, Antarctica by Rita Willaert. Creative Commons Attribution-Noncommercial 2.0 Generic
Story courtesy of X-Journals @
http://x-journals.com/2009/prehistoric-global-cooling-caused-by-co2-declines-research-finds/
Tuesday, February 24, 2009
New paper details the decline of emperor penguins
Demographic models and IPCC climate projections predict the decline of an emperor penguin population
1. Stéphanie Jenouvriera,b,1,
2. Hal Caswella,1,
3. Christophe Barbraudb,
4. Marika Hollandc,
5. Julienne Strœved and
6. Henri Weimerskirchb
+Author Affiliations
1.
aDepartment of Biology, MS-34, Woods Hole Oceanographic Institution, Woods Hole, MA 02543;
2.
bCentre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, F-79360 Villiers en Bois, France;
3.
cOceanography Section, National Center for Atmospheric Research, Boulder, CO 80305; and
4.
dNational Snow and Ice Data Center, Boulder, CO 80309
1.
Edited by Joel E. Cohen, The Rockefeller University, New York, NY, and approved December 2, 2008 (received for review July 10, 2008)
Abstract
Studies have reported important effects of recent climate change on Antarctic species, but there has been to our knowledge no attempt to explicitly link those results to forecasted population responses to climate change. Antarctic sea ice extent (SIE) is projected to shrink as concentrations of atmospheric greenhouse gases (GHGs) increase, and emperor penguins (Aptenodytes forsteri) are extremely sensitive to these changes because they use sea ice as a breeding, foraging and molting habitat. We project emperor penguin population responses to future sea ice changes, using a stochastic population model that combines a unique long-term demographic dataset (1962–2005) from a colony in Terre Adélie, Antarctica and projections of SIE from General Circulation Models (GCM) of Earth's climate included in the most recent Intergovernmental Panel on Climate Change (IPCC) assessment report. We show that the increased frequency of warm events associated with projected decreases in SIE will reduce the population viability. The probability of quasi-extinction (a decline of 95% or more) is at least 36% by 2100. The median population size is projected to decline from ≈6,000 to ≈400 breeding pairs over this period. To avoid extinction, emperor penguins will have to adapt, migrate or change the timing of their growth stages. However, given the future projected increases in GHGs and its effect on Antarctic climate, evolution or migration seem unlikely for such long lived species at the remote southern end of the Earth.
PDF can be downloaded here:
http://www.pnas.org/content/106/6/1844
1. Stéphanie Jenouvriera,b,1,
2. Hal Caswella,1,
3. Christophe Barbraudb,
4. Marika Hollandc,
5. Julienne Strœved and
6. Henri Weimerskirchb
+Author Affiliations
1.
aDepartment of Biology, MS-34, Woods Hole Oceanographic Institution, Woods Hole, MA 02543;
2.
bCentre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, F-79360 Villiers en Bois, France;
3.
cOceanography Section, National Center for Atmospheric Research, Boulder, CO 80305; and
4.
dNational Snow and Ice Data Center, Boulder, CO 80309
1.
Edited by Joel E. Cohen, The Rockefeller University, New York, NY, and approved December 2, 2008 (received for review July 10, 2008)
Abstract
Studies have reported important effects of recent climate change on Antarctic species, but there has been to our knowledge no attempt to explicitly link those results to forecasted population responses to climate change. Antarctic sea ice extent (SIE) is projected to shrink as concentrations of atmospheric greenhouse gases (GHGs) increase, and emperor penguins (Aptenodytes forsteri) are extremely sensitive to these changes because they use sea ice as a breeding, foraging and molting habitat. We project emperor penguin population responses to future sea ice changes, using a stochastic population model that combines a unique long-term demographic dataset (1962–2005) from a colony in Terre Adélie, Antarctica and projections of SIE from General Circulation Models (GCM) of Earth's climate included in the most recent Intergovernmental Panel on Climate Change (IPCC) assessment report. We show that the increased frequency of warm events associated with projected decreases in SIE will reduce the population viability. The probability of quasi-extinction (a decline of 95% or more) is at least 36% by 2100. The median population size is projected to decline from ≈6,000 to ≈400 breeding pairs over this period. To avoid extinction, emperor penguins will have to adapt, migrate or change the timing of their growth stages. However, given the future projected increases in GHGs and its effect on Antarctic climate, evolution or migration seem unlikely for such long lived species at the remote southern end of the Earth.
PDF can be downloaded here:
http://www.pnas.org/content/106/6/1844
X-rays Reveal Famous Dinobird's Secrets
X-rays Used To Reveal Secrets Of Famous 'Dinobird' Fossil
ScienceDaily (Feb. 22, 2009) — About 150 million years ago, an evolutionarily hybrid creature, a dinosaur on its way to becoming a bird, died in what is now Germany, and become fossilized in limestone.
About 150 years ago, the fossil of this "dinobird" was discovered and celebrated as proof of Charles Darwin's new theory of evolution.
Now fast word to a few weeks ago: The famous fossil, the Thermopolis specimen of Archaeopteryx lithographica, made its way by truck from the Wyoming Dinosaur Center to the Stanford Synchrotron Radiation Lightsource in California, where it was meticulously scanned by one of the world's most powerful X-ray machines, a building-sized device created for physics research.
By looking for traces of specific elements left in the slab of limestone as the bird decomposed, the researchers hope to uncover heretofore-unseen details of the soft tissue that once surrounded the well-preserved bones.
The X-rays, generated by SSRL's high-speed electrons as they race around a 260-foot-diameter ring, cause the elements to glow, revealing the ghost of soft tissue or feathers.
"If you want to find a single fossil which is a missing link in the evolution of dinosaurs into birds, this is it," said University of Manchester paleontologist Phil Manning, a member of the research team. "It's a bird with sharp teeth, claws and a long bony tail. If you were to freeze-frame evolution, you would end up with Archaeopteryx."
"What you normally can't see are the chemical elements from the original organism that might still be present in the fossil," said SSRL scientist Uwe Bergmann. "Using X-ray fluorescence imaging, we can bring these elements to light, getting a better look at the fossil and learning more about the original animal."
"These X-rays work a thousand time better than what you could do with a commercial X-ray machine. Only a synchrotron can do this," Bergmann said. SSRL is part of SLAC National Accelerator Laboratory, which is operated by Stanford University for the Department of Energy.
In addition to offering a new view of a long-extinct animal, this work may also reveal more about fossilization itself. By understanding how fossilization occurs and what exactly is preserved in the process, researchers will be able to deduce much more about ancient organisms and evolution.
The Archaeopteryx fossil holds a unique place in history. It was brought to London soon after Darwin published his stunning On the Origin of Species in 1859. With perfect timing, the old bones played a major roll in the controversy Darwin had stirred up.
"This fossil was the savior of Darwin," Manning said. "As soon as it arrived in London, all of Darwin's supporters realized that this was an intermediate animal, an evolutionary freak that they needed to study. It was half way between dinosaur and bird. This is the single most important fossil in paleontology for that simple reason.
"It was used to beat the living daylights out of the nonsense which had been put forward as to the reason for why animals were present on this planet. Here, Darwin's theory of descendant with modification was hammered home with this one example of transitionary form, of an animal between dinosaur and bird."
The fossil research is one example of how the SSRL is shining new light on fields as diverse as paleontology, medicine, and the history of mathematics. The SSRL's hair-thin X-ray beam has been used, for example, to make visible the hidden writing in a medieval copy of a mathematical treatise from the Greek mathematician Archimedes. Tuned to specific energies, the X-rays produced images of phosphorus and calcium from the ink used on the papyrus document, which had been covered with paint.
Earlier this year, at the request of Stanford library officials and an academic researcher, the laser-like X-ray beam was used to scan a score by the Italian composer Luigi Cherubini (1760 – 1842). Portions of the work had been covered over with carbon-black ink, but after the scan, "The researcher was able to look right through the ink and read the score," said Mary Miller, a Stanford preservation librarian. "I think he was thrilled."
"This is the very infancy of this new scientific method," said paleontologist Peter Larson of the Black Hills Institute in South Dakota. "We don't even know enough about this to know the right questions to ask yet. All of a sudden, we can look at fossils in a very different and new way."
Adapted from materials provided by Stanford University. Original article written by Dan Stober.
Stanford University. "X-rays Used To Reveal Secrets Of Famous 'Dinobird' Fossil." ScienceDaily 22 February 2009. 24 February 2009
Friday, February 20, 2009
Yellow-eyed penguin (Megadyptes antipodes)
Yellow-eyed penguin (Megadyptes antipodes)
Facts
Also known as: the 'Hoiho'
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Megadyptes (1)
Size Length: 65 – 68 cm (2)
Weight 5 – 8 kg (2)
Status
Classified as Endangered (EN) on the IUCN Red List 2007 (1).
Description
The yellow-eyed penguin is one of the most endangered of all penguin species (3). These birds are slate grey with a white breast. As their common name suggests they have yellow eyes, accentuated by the yellow band that runs from the eyes around the back of the head (4). Males and females are identical but juveniles lack the yellow eyes and bands of older birds (2). The Maori name for these birds is ‘Hoiho', which means ‘the noise shouter' in reference to their shrill call (5).
Range
Endemic to New Zealand, breeding takes place on the southeast coast of South Island and on Foveaus Strait, Stewart, Auckland and Campbell Islands (6).
Habitat
Yellow-eyed penguins breed in forest or scrubland, choosing to build nests against rocks or tree trunks, which provide some protection from the elements (2).
Biology
Yellow-eyed penguins are not particularly sociable, breeding in spaced-out territories in the forest rather than the close-knit colonies of other species (3). Pairs are monogamous and stay together for life. The breeding season is particularly long, beginning with courtship in August; the clutch of two eggs is laid in mid-September to mid-October on a nest constructed from sticks (2). Both parents help to incubate the eggs, which can take up to two months. For the next six weeks the adults will take it in turns to stay with the chick whilst the other forages for food (2).
Penguins moult once a year but during this time they need to remain on land while the feathers are replaced (3). The three-week moult takes place in February and March following the fledging of the chicks. Penguins need to accumulate considerable resources before this takes place, as they can loose up to four kilograms of body weight during the moult (2). Yellow-eyed penguins feed on a variety of fish including red cod, opal fish, sprat and silversides. They tend to forage within 15 kilometres (2) of the shore and can dive up to 160 metres (3).
Threats
The yellow-eyed penguin may be the rarest penguin in the world. The coastal forests of their habitat, particularly of mainland New Zealand, have been destroyed to make way for development and agriculture. Introduced sheep and cattle pose a threat as they can trample on penguin nests and overgraze the area, destroying further habitat (2). In 1986 and 1990 there were two major population crashes, the causes of which remain a mystery (6). The other major threat to the yellow-eyed penguin comes from introduced mammalian predators such as ferrets, cats, rats and dogs; juvenile penguins or adults during their moult phase are extremely vulnerable to predation and numbers have been decimated over the years (2).
Conservation
The New Zealand Department of Conservation Hoiho Recovery Plan is currently underway, which aims to promote the recovery of this species and to involve local people in their conservation (5). A number of schemes are already in place including the protection of certain key habitats and the removal of predators. The Yellow-eyed Penguin Trust has introduced a number of important conservation initiatives and research, including the banning of dogs from certain sensitive beaches (2). The Trust is careful to work extremely closely with local residents over these sensitive issues (2). Every effort is being made to secure the future of one of New Zealand's avian treasures.
Further Information
For more information on the yellow-eyed penguin see:
* Yellow-eyed Penguin Trust:
www.yellow-eyedpenguin.org.nz
* New Zealand Department on Conservation:
www.doc.govt.nz/templates/podcover.aspx?id=33022
References
1. IUCN Red List (February, 2008)
http://www.iucnredlist.org
2. Yellow-eyed Penguin Trust (August, 2003)
http://www.yellow-eyedpenguin.org.nz/
3. International Penguin Conservation Work Group (August, 2003)
http://www.penguins.cl/yellow-penguins.htm
4. New Zealand Penguins (February, 2008)
http://www.penguin.net.nz/species/yep/index.html
5. NZ Department of Conservation (August, 2003)
http://www.doc.govt.nz/templates/podcover.aspx?id=33022
6. BirdLife International (August, 2003)
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3859&m=0
Information and images courtesy of ARKive @
http://www.arkive.org/yellow-eyed-penguin/megadyptes-antipodes/image-G8014.html
Thursday, February 19, 2009
Paleo Flyers' First Flight Mechanism
Science News
Air-filled Bones Extended Lung Capacity And Helped Prehistoric Reptiles Take First Flight
ScienceDaily (Feb. 18, 2009) — In the Mesozoic Era, 70 million years before birds first conquered the skies, pterosaurs dominated the air with sparrow- to Cessna-sized wingspans. Researchers suspected that these extinct reptiles sustained flight through flapping, based on fossil evidence from the wings, but had little understanding of how pterosaurs met the energetic demands of active flight.
A new study published February 17 in the journal PLoS One by researchers from Ohio University, College of the Holy Cross and the University of Leicester explains how balloon-like air sacs, which extended from the lungs to inside the skeleton of pterosaurs, provided an efficient breathing system for the ancient beasts. The system reduced the density of the body in pterosaurs, which in turn allowed for the evolution of the largest flying vertebrates.
"We offer a reconstruction of the breathing system in pterosaurs, one that proposes the existence of a mechanism with the same essential structure to that of modern birds — except 70 million years earlier," said study co-author Leon Claessens, an assistant professor of biology at the College of the Holy Cross.
The system would have facilitated the necessary gas exchange to enable sustained activity, added co-author Patrick O'Connor, an assistant professor of biomedical sciences at the Ohio University College of Osteopathic Medicine.
Claessens and O'Connor were inspired to conduct the study after David Unwin of the University of Leicester, then curator at the Natural History Museum in Berlin, showed them an extraordinarily preserved pterosaur in 2003. The scientists thought the specimen might finally shed light on how the animals powered sustained flight.
"The shape and size of the rib segments that articulate with the sternum indicate that the ribcage was mobile, contrary to previous ideas," Claessens said.
Unique and previously unrecognized projections on the ribs provided important leverage for the muscles that power lung ventilation, he added.
Because fossils rarely preserve soft tissues, the research team conducted a comparative study that included pterosaurs, birds and crocodilians in order to get a better understanding of the relationships among air sacs, lung structure and the skeleton. By using X-ray movies and CT scans, the group characterized how the skeleton works to move air through the lungs in living animals, and also how to identify the signature traces left on bones that have been invaded by air sacs.
Not only do the extinct pterosaurs show evidence that their bones that were invaded by air sacs, but patterns of pneumaticity throughout the entire skeleton of different pterosaur species parallel trends identified in many living bird groups. For example, there is a direct relationship between the proportion of the skeleton invaded by air sacs and the absolute body size of an animal.
"Whereas small-bodied pterosaurs and birds typically pneumatize only a restricted part of the backbone, larger-bodied species routinely pneumatize most bones of the body, including the wing skeleton out to the ends of the fingers," O'Connor said.
Such modifications of the skeleton would have reduced bone density and resolved a major problem with sustaining flight in large-bodied pterosaurs: the energetic cost of keeping a heavy body up in the air. Density reduction of the skeleton in pterosaurs may have been beneficial, particularly so in the aerial giants—just as it appears to be in the largest flying birds today.
Air sacs in birds also serve other purposes, such as for visual displays and the production of sound, the researchers said. The existence of an analogous air-sac system in pterosaurs highlights new areas of research in which paleobiologists can explore aspects of pterosaurian biology.
The research was funded by the National Science Foundation, Harvard University, and the Ohio University College of Osteopathic Medicine and Office of Research.
Adapted from materials provided by Ohio University, via EurekAlert!, a service of AAAS.
Ohio University. "Air-filled Bones Extended Lung Capacity And Helped Prehistoric Reptiles Take First Flight." ScienceDaily 18 February 2009. 19 February 2009 <http://www.sciencedaily.com /releases/2009/02/090217212305.htm>.
Tuesday, February 17, 2009
Why Penguins Are Important
Penguins are important
Why Penguins Are More Important Than Ever For the Average American - By Michael Tobias and Jane Gray Morrison
Several of the 17 species of penguin worldwide are in trouble: they face the very real possibility of extinction in this century. Most people love penguins. Therefore, most people are in trouble, goes the logic.
It may seem a reach to suggest that what happens in the deep icy southern hemisphere should really matter at the moment to Americans worried about paying their mortgages, or having a job tomorrow morning. And even if it does matter, goes the thinking, there is not a whole lot an individual can do to rescue the very rare Yellow-Eyed Penguins found in a few parts of New Zealand from potential oblivion, especially given the long-term trends and fall-out from global warming, a critical factor imperiling the birds.
However, this is not entirely so. The same factors influencing penguins, will also, according to Energy Secretary Steven Chu, mean the possible demise of all agriculture in the State of California by century’s end which, he added, could mean the collapse of California’s major cities.
There is no escaping the fact the economic story of all nations mirrors precisely the greater ecological tapestry and imperatives that govern all money-related matters, namely, the biosphere and all of its biological parts. With as much as 50% or more of all life hanging in the balance depending upon what people do, or fail to do in coming years, we must get it right. That means factoring conservation into everything we tackle and think about; conservation of fresh water, clean air, the soil, wetlands and forests, oceans and streams.
We know many, though by no means all, of the vital connections to our health that nature implicitly provides. Frogs, for example, consume insects that transmit malaria. Malaria appears to be again mutating and killing millions of our kind, while we serve up hundreds of millions of frog legs every year on dinner plates, while at the same time destroying the habitat for those frogs that don’t get eaten. A recent discovery of several new healthy frog species in Columbia’s mostly remote Darien region shows that a vast amount of biodiversity is still out there – possibly 100 million species. There may be enough time to make this all work, to do our part to ensure the continuity of life on the planet. But it won’t happen unless we are deliberate, swift and conscientious about it.
According to the U.S. Food and Drug Administration, roughly 62% of all drugs approved for cancer treatments come from a natural origin. What is keeping us alive is nature. But of the more than 400,000 known plant species, at least half are in danger of disappearing because of our actions. Well then, it should be obvious what we need to do: Save the plants, and much more. There are plenty of immediate financial incentives for doing so, if fundamental self-preservation of our species seems too vague an incentive.
A recent report entitled “Building Biodiversity Business”(*1) suggests profound opportunities for sustainable ecologically-based enterprises that are profitable: $120 billion for wildlife-related recreational activities in the U.S.; $30 million acres under sustainable organic agriculture in Australia; $620 billion accruing from global environmental goods and services worldwide in 2005; $3.6 trillion in annual tourism revenues, employing some 200 million people where the largest gains appear to be happening specifically in the eco-tourism sectors; $50 billion per year from the Kyoto Protocol carbon markets and growing; and, to top it all, probably the most profitable enterprise of all now fast emerging: alternative energy, formidably detailed in the new McKinsey Report (*2). Witness California’s rapid ascendancy in the realm of new hybrids. While the state’s budget is in dire trouble, don’t forget that some $45 billion in payroll in that state comes from policies mandating higher energy efficiency and environmentally clean technologies, the same amount of money needed each year as projected by scientists to stabilize global ecosystems and prevent a raft of unprecedented extinctions. Moreover, the same offsets that are being utilized to understand and pave the way for carbon markets, are now being embraced by several countries as well as banks – from the U.S. to South Africa to Switzerland - with respect to actual biodiversity offsets. A single acre of saved wetland can be worth as much as several hundred thousand dollars of mitigation value. Biodiversity business is just now in its infancy.
Recent discussion of a renewed Conservation Corps to help the National Parks, which first occurred under President Theodore Roosevelt with the mobilizing of a massive workforce of hundreds-of-thousands of recruits during the Great Depression to places like Yosemite, is one terrific idea. Billions of trees were planted across the U.S. as a result of that. Many other great notions are staring us in the face, from windows on every house and building that can be made to generate electricity, to opportunities in the classroom to convert every student into an ardent defender of wildlife, whether plants, mountain lions, or the very penguins who co-habit American bases in the Antarctic, like McMurdo and Palmer. The lives of those penguins depend upon the variation of a few degrees Celcius that affect the survival of the marine food sources that also support all creatures, great and small throughout the oceans.
Where serious gaps remain across America’s biological landscape, particularly wild-lands earmarked for road access and resource extraction, monoculture, suburban sprawl and countless other forms of biological fragmentation, there is by now a clear consensus that Americans overwhelmingly care about these issues as witnessed in the wilderness bill S.22 just passed by the Senate. People want their children to have a deeper connection to nature than merely experiencing it as stuffed in museums, caged in zoos or digitized on television. The economic opportunities all point to a renaissance in nature appreciation, park visits, and new protected areas that can help Americans, and people everywhere, get through depressing times. As New York Times columnist and author Thomas Friedman writes, “Green is the new Red, White and Blue.”
(*1) Joshua Bishop, Sachin Kapila, Frank Hicks, Paul Mitchell and Francis Vorhies, Copyright 2008 by Shell Intl. Ltd., the IUCN, and the authors.
(*2) The McKinsey report, Pathways to a Low Carbon Economy, available online at: http://www.worldwildlife.org/climate/mckinseyreport.html
Story courtesy of The Westender @
http://www.westender.com.au/news/405/15/Penguins-are-important
Saturday, February 14, 2009
Penguins Marching Into Trouble
Science News
Penguins Marching Into Trouble
ScienceDaily (Feb. 13, 2009) — Imagine you live in the suburbs of Chicago and you must commute hundreds of miles to a job in Iowa just to put food on the table. Magellanic penguins living on the Atlantic coast of Argentina face a similar scenario, and it is taking a toll.
The penguins' survival is being challenged by wide variability in conditions and food availability, said Dee Boersma, a University of Washington biology professor and a leading authority on Magellanic penguins.
For example, while one parent incubates eggs on the nest the other must go off to find food. But these days, Boersma said, penguins often must swim 25 miles farther to find food than they did just a decade ago.
"That distance might not sound like much, but they also have to swim another 25 miles back, and they are swimming that extra 50 miles while their mates are back at the breeding grounds, sitting on a nest and starving," she said.
Boersma has recently published research documenting some of the serious challenges faced by Magellanic penguins in a colony at Punta Tombo, Argentina, that she has studied for more than 25 years. She discusses her research Thursday (Feb. 12) during a news briefing and Friday during a symposium at the American Association for the Advancement of Science meeting in Chicago.
The Punta Tombo colony has declined more than 20 percent in the last 22 years, leaving just 200,000 breeding pairs, Boersma said.
There are several reasons for the decline, including oil pollution and overharvesting of fish by humans. Climate variation also is a major problem, she found.
Longer trips for food during a given breeding season lessen the chances that a given penguin pair will successfully reproduce. Some younger penguins move to colonies that are closer to food one year but might be farther away from food the following year. Increased ocean variability means penguins often return to their breeding grounds later and are in poorer condition to breed.
They also are increasingly subject to having their desert nests flooded by rain. Five times in the last 25 years, Boersma said, the Punta Tombo reserve has recorded about 2.5 inches of rain between Oct. 15 and Dec. 16, which threatens the survival of eggs and small chicks.
"That turns their little nests into swimming pools," she said.
In addition, there have been increasing instances of El Niño-like events that alter ocean currents, forcing penguins to travel farther for the fish on which they feed. Increasingly, Boersma has found that penguins she tagged at Punta Tombo years ago are turning up in colonies as much as 250 miles farther north. Birds migrating in search of food are forming the new colonies, but often they end up on land that is not part of a government preserve like Punta Tombo is.
The problems don't just confront Magellanic penguins, said Boersma, director of the Wildlife Conservation Society's Penguin Project. Of 17 penguin species, 12 are experiencing rapid population declines. The least concern is for the emperor, king, Adélie, little blue and chinstrap penguins, she said. All the rest are nearly threatened, threatened or endangered.
She noted that the success of Argentine fishing fleets is a good signal for how the Magellanic penguins will fare in a given winter as they store nutrition to prepare for the breeding season. There is a small anchovy fishery in the winter, and penguins also favor anchovies. But when the boats don't do well catching anchovies in the winter, that is bad news for penguins in the following breeding season.
"They do well when the fishermen are catching anchovies. If the fishermen are not successful, the penguins start to falter," Boersma said. "If the fishery expands and then collapses, as most do, the penguins will be in trouble.
"Penguins are having trouble with food on their wintering grounds and if that happens they're not going to come back to their breeding grounds," she said. "If we continue to fish down the food chain and take smaller and smaller fish like anchovies, there won't be anything left for penguins and other wildlife that depend on these small fish for food."
Of the world's 17 species of penguins 12 are rapidly declining Boersma added.
University of Washington. "Penguins Marching Into Trouble." ScienceDaily 13 February 2009. 14 February 2009
Friday, February 13, 2009
Spheniscus demersus (The African Penguin)
Facts
Also known as: jackass penguin
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Spheniscus (1)
Size Length: 60 - 70 cm (2)
Status
Classified as Vulnerable (VU) on the IUCN Red List 2007 (1). Listed on Appendix II of CITES (3), and Appendix II of the Convention on Migratory Species (CMS or Bonn Convention) (4).
Description
The African penguin is a medium-sized penguin, and the only species breeding on the African continent (5). Penguins have a robust, heavyset body and this species are black on the back and white below, with variable black markings on the breast and belly (2). Juvenile plumage is slate blue on the upper surface and this gradually turns darker, developing the adult black-and-white facial pattern in the second or third year. Penguins have small muscles at the base of each feather that enable them to be held tightly against the body whilst in water, forming a waterproof layer; alternatively, on land they are held erect, trapping an insulating layer of air around the body (5). These penguins are also known as ‘jackass penguins' due to their loud, braying call (6).
Range
Found in southern Africa, these penguins are known to breed on 24 islands between Hollamsbird Island, Namibia and Bird Island in Algoa Bay, South Africa (2).
UNEP World Conservation Monitoring Centre View a distribution map for this species at UNEP World Conservation Monitoring Centre.
Habitat
African penguins are generally found within 40 kilometres of the coast, emerging onto rocky offshore islands to breed, rest and moult (2).
Biology
African penguins are colonial breeders with pairs returning to the same site year after year. Unusually, there is no fixed breeding season although nesting peaks in Namibia between November and December and in South Africa between March and May. Nests are situated in burrows or depressions under boulders and bushes where they will receive some protection from the potentially harsh temperatures (5). The clutch size is usually two and both parents take it in turns to incubate the eggs for a period of about 40 days; penguins have a bare patch of skin on the lower abdomen (known as the ‘brood patch'), which allows greater transfer of heat to the eggs. Following hatching, the adults will continue to guard the chicks until they are about 30 days old, regurgitating food straight from their stomach following foraging trips. Chicks are then left alone in crèches whilst their parents forage; at between 60 and 130 days old they develop juvenile plumage and leave the colony (5).
These penguins feed on fish such as anchovies (Engraulis capensis) and sardines (Sardinops sagax) (2). Adapted for their aquatic lifestyle, African penguins can reach speeds of 20 kilometres per hour in the water and range from 30 to 70 kilometres in a single trip; average dives last for 2.5 minutes, reaching depths of 60 metres. Penguins have waterproof coats that need to be constantly maintained by preening, when a waxy substance is distributed from the base of the tail. Even with these measures, their plumage is replaced yearly and African penguins come ashore to moult over 20 days between November and January in South Africa and between April and May in Namibia (5).
Threats
The population of African penguins has declined and it is estimated that its current size is a mere 10 percent of what it was at the turn of the 20th Century. Originally the fall in numbers was the result of the over-collection of eggs for food, and disturbance caused by the collection of guano for fertiliser. Today, however, depleted fish stocks due to over-fishing, and the risk of oil pollution are the most pertinent threats to the survival of this species (5); a recent oil spill affected around 40 percent of the population. Predation by Cape fur seals (Arctocephalus pusillus) and competition with them for food and breeding sites, as well as shark predation, has also had severe effects on population numbers (2).
Conservation
The African penguin is protected by its listing on Appendix II of the Convention on International Trade in Endangered Species (CITES) (3), and on Appendix II of the Convention on Migratory Species (CMS) (4). All of the breeding areas in South Africa are protected as National Parks or Nature Reserves and the collection of guano or eggs is no longer permitted. The recovery of rescued oiled birds has also been shown to be successful. Populations need further monitoring and the possibility of conserving fish stocks is under investigation, amongst other measures, if the future of Africa's only penguin is to be secured (2).
For further information on the African penguin see:
* BirdLife International:
www.birdlife.org
* International Penguin Conservation:
www.penguins.cl
* South African Foundation for the Conservation of Coastal Birds:
www.sanccob.co.za/index.htm
Authentication
Authenticated (01/06/05) by Samantha Petersen, Seabird Conservation Programme Manager, BirdLife South Africa.
http://www.birdlife.org.za/index.cfm
References
1. IUCN Red List (September, 2007)
http://www.iucnredlist.org
2. BirdLife International (April, 2003)
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3861&m=0
3. CITES (April, 2003)
http://www.cites.org
4. Global Register of Migratory Species (March, 2008)
http://www.groms.de
5. International Penguin Conservation (April, 2003)
http://www.penguins.cl
6. Animal Diversity Web (April, 2003)
http://animaldiversity.ummz.umich.edu/accounts/spheniscus/s._demersus$narrative.html
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From the IFAW Web Site
Classification:
Scientific Name: Spheniscus demersus
Class: Aves
Order: Sphenisciformes
Family: Spheniscidae
Genus: Spheniscus
Species: demersus
Distribution Map
Physical Description
The African, or jackass, penguin is a medium-sized penguin which stands about 45 centimeters (18 inches) tall and has a total body length of about 60 centimeters (24 inches). Males weigh an average of 3.6 kilograms (8 pounds) and females an average of 3.1 kilograms (7 pounds). However, they look extremely similar in the wild and small males may be smaller than large females.
Like all penguins, African penguins have a short, thick neck, a streamlined body and a short, wedge-shaped tail with small flipper-like wings. They are black on the back and wings, with a black band across the chest, and black cheeks. The bill is black with a light band around it. They have a white belly with black spots or speckles, black webbed feet and black claws. This fast-swimming penguin gets its nickname of "jackass" from the donkey-like call of territorial males.
Natural History
African penguins are endemic to South Africa and Namibia. They are distributed from Transkei to northern Namibia and breed in densely packed groups (colonies or rookeries) from Bird Island, Algoa Bay, to Hollams Bird Island, Namibia.
African penguins return to the same nest site and, usually, to the same partner each year. Because they are ground nesters, they require predator-free breeding areas and are therefore limited by the availability of predator-free islands and mainland areas. They nest in burrows in the sand, under overhanging rocks and bushes, or in the open. They used to nest in guano (bird droppings), but most of the guano was removed for fertilizer in the 19th century, causing destruction of most of this breeding habitat.
The breeding season usually starts in January on the islands and each pair usually lays two eggs, three or four days apart. Eggs are incubated by both parents for 38 days each. One parent guards the nest while the other feeds on anchovy, pilchard, horse mackerel and round herring. Chicks are born with gray down and are fed regurgitated food. Usually only the first chick survives, as there is insufficient food for two. The surviving chick fledges between 80 and 130 days depending on foraging conditions and proficiency of parents in providing food.
African penguins molt each year at their breeding island. As the insulating qualities of their feathers break down, they are no longer able to keep warm, and their feathers must be replaced. For the 21-day molt, the penguins are land-bound, unable to swim or feed. To prepare for it, they feed extensively for about five weeks before the molt begins.
The population of African penguins has crashed from at least 1.2 million in 1930 to 100,000 in 1978. The species is continuing to decline.
Status
Local conservation measures include permit-access-only to breeding islands, control of feral cats, and the restriction of fur seals onto penguin breeding areas.
Cleaning and rehabilitation of oiled birds is carried out by the private South African National Foundation for the Conservation of Coastal Birds (SANCCOB).
The African jackass penguin is listed as Vulnerable by the International Union for the Conservation of Nature and Natural Resources (IUCN). The drastic decline in their numbers is expected to continue and may result in the extinction of this species in 70 years. The African penguin is also listed on Appendix II by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
Threats to the Species
Historically, harvesting of eggs for human consumption was a major threat. Although a limited amount of egg collecting continues, the commercial harvest of eggs stopped in 1967 and is illegal today. Today, oil pollution from tankers cleaning their bilges and from oil spills are major threats. African penguins are also threatened by destruction of breeding habitat, competition for breeding space with other animals (e.g. fur seals), disturbance of breeding animals on the mainland by humans, vulnerability to predators such as leopards and dogs, and reduced prey availability due to commercial fishing. Some penguins are still killed and used as bait in certain fisheries.
International Trade
No legal trade.
Sources
CITES. 2001. African penguin. http://www.cites.org.
Enchanted Learning.com. 2001. Jackass penguin. http://www.zoomschool.com.
IUCN. 2001. The 2000 IUCN Red List of Threatened Species—Spheniscus demersus. http://www.redlist.org.
Payne, A.I.L. and R.J.M. Crawford. 1989. Oceans of life off southern Africa. Claeberg Publishers, Cape Town. 380pp.
UWC Enviro Facts. 2001. Jackass penguin. http://www.botany.uwc.ac.za.
First article and pics courtesy of ARKive @
http://www.arkive.org/african-penguin/spheniscus-demersus/info.html
Want to help? Go here, to the second source for the article and map:
http://www.ifaw.org/ifaw_southern_africa/save_animals/other/african_penguin.php
Sunday, February 8, 2009
Saturday, February 7, 2009
Image of the Day
Summer 2008 at Sea World of Orlando... click on and enlarge the photo for the best quality.
Friday, February 6, 2009
Wednesday, February 4, 2009
Southern rockhopper penguin (Eudyptes chrysocome)
Southern rockhopper penguin (Eudyptes chrysocome)
Facts:
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Eudyptes (1)
Size Length: 52 cm (2)
Weight 3 kg (2)
Status
Classified as Vulnerable (VU) on the IUCN Red List (1).
Description
Previously classed as a single species, the rockhopper penguin has now been split into a northern (Eudyptes moseleyi) and southern species (Eudyptes chrysocome) (3). Although both species are similar in appearance, the distinctive yellowish plumes extending from the yellow line above the eye are significantly shorter and less dense in the southern rockhopper penguin (2) (3). The body is small but robust, with slate-grey upperparts and white underparts, the bill is short and reddish-brown and the eyes are red. Juveniles can be identified by the lack of adult yellow markings (2).
Range
The southern rockhopper penguin breeds on a number of Southern Ocean islands. Two subspecies are currently recognised, Eudyptes chrysocome chrysocome, which is found in the Falkland Islands, Isla Pinguino, Staten Island, and islands off southern Chile and Argentina, and Eudyptes chrysocome fiholi, which is found on several subantarctic islands to the south of New Zealand and South Africa (4).
Habitat
Nesting occurs on cliffs and rocky gullies, and chosen sites are usually situated near to freshwater, either natural springs or puddles (2).
Biology
A gregarious species, the southern rockhopper penguin breeds in large colonies that may comprise over a hundred thousand nests. Breeding pairs are monogamous, and usually return to the same nest every year. Egg-laying commences around November, with the female usually producing a clutch of two eggs of unequal size (2). Although, in general, only the chick from the larger egg survives to maturity, populations on the Falkland Islands frequently succeed in raising both (5). Incubation takes around 33 days, with both parent birds taking it in turns to sit on the eggs for extended periods of a time, whilst the other forages for food. Incubation is aided by a bare patch of skin on the lower abdomen (known as a 'brood pouch') that allows greater heat transfer to the egg. Once hatched, the male will remain to brood the chick for the first 25 days, whilst the female regularly brings food back to the nest. After this time, the chick is able to leave the nest, and will congregate with other chicks in small groups known as 'crèches' whilst the parent birds forage (2).
In order to maintain its waterproof coat, the southern rockhopper penguin engages in frequent grooming, which helps to flatten the feathers and to spread a waxy substance that is secreted just below the tail. Grooming is also an important social bond between pairs. After breeding the southern rockhopper penguin forages extensively in order to build up fat reserves in preparation for its annual moult. It takes around 25 days for the penguin's coat to be fully replaced, at which point it leaves the land and spends the winter months foraging at sea, before returning to shore to breed in the following spring (2). The diet of the southern rockhopper penguin is composed of a variety of oceanic species, such as crustaceans, squid, octopus and fish (4). Groups may often feed together and dives may be to depths of up to 100 metres (2).
Threats
Some southern rockhopper penguin nesting colonies have recently shown dramatic falls in numbers of breeding pairs. The Falkland Islands once housed the stronghold for southern rockhopper penguins, but over the last 60 years, numbers have declined by 90% (4). The reasons for these declines range from increasing disturbance and pollution, to declining fish stocks as a result of over fishing, failure to provide no-fishing zones around penguin colonies (6) and global warming (4).
Conservation
Many islands that house breeding colonies have been designated as reserves and the populations in the Falklands, Marion, Campbell Islands are regularly monitored and studied (4). Greater investigation of population demographics and of potential threats is required. Following the starvation of over 100,000 rockhopper penguins in the Falkland Islands, the Spheniscus Penguin Conservation Work Group published a report recommending that commercial fishing be excluded within 30 miles of penguin breeding sites (2). These measures have been adopted around southern Chile and Argentina, and these sites are healthy and increasing as a result. The adjacent Falklands have refused to introduce such protection, and populations continue to decline (6).
Further Information
To learn more about penguin conservation visit:
* International Penguin Conservation:
http://www.penguins.cl
* Falklands Conservation:
www.falklandsconservation.com
* Organisation for the Conservation of Penguins: English:
http://www.seabirds.org Spanish:
http://seabirds.org/chile.htm
References
1. IUCN Red List (January, 2009)
http://www.iucnredlist.org
2. International Penguin Conservation (January, 2009)
http://www.penguins.cl
3. Jouventin, P., Cuthbert, R.J. and Ottvall, R. (2006) Genetic isolation and divergence in sexual traits: evidence for the northern rockhopper penguin Eudyptes moseleyi being a sibling species. Molecular Ecology, 15: 3413 - 3423.
4. BirdLife International (January, 2009)
http://www.birdlife.org
5. Poisbleau, M., Demongin, L., Strange, I.J., Otley, H. and Quillfeldt, P. (2008) Aspects of the breeding biology of the southern rockhopper penguin Eudyptes c. chrysocome and new consideration on the intrinsic capacity of the A-egg. Polar Biology, 31: 925 - 932.
6. Bingham, M. (2002) The decline of Falkland Islands penguins in the presence of a commercial fishing industry. Revista Chilena de Historia Natural, 75: 805 - 818. Available at:
http://www.seabirds.org/resume.htm
All images and information courtesy of ARKive @
http://www.arkive.org/southern-rockhopper-penguin/eudyptes-chrysocome/image-G5895.html
See this page's links section for link to ARKive general.