Recommendations for Reading

Click here for a fascinating article on penguin eggs

I recommend NZ's Fossil Penguin Site-click this line

Read about Palaeeudyptes antarcticus here

Read more about Kairuku - the new "giant" Late Oligocene Penguin from New Zealand

The Rockhopper Penguin

Eudyptes chrysocome
rockhopper penguin

By Devon Phelan

• Classification

Kingdom Animalia (animals)
Eumetazoa (metazoans)
Bilateria (bilaterally symmetrical animals)
Deuterostomia (deuterostomes)
Phylum Chordata (chordates)
Craniata (craniates)
Subphylum Vertebrata (vertebrates)
Superclass Gnathostomata (jawed vertebrates)
Euteleostomi (bony vertebrates)
Class Sarcopterygii (lobe-finned fishes and terrestrial vertebrates)
Tetrapoda (tetrapods)
Amniota (amniotes)
Class Reptilia
Class Aves (birds)
Subclass Neognathae (neognath birds)
Infraclass Neoaves (modern birds)
Order Sphenisciformes (penguins)
Family Spheniscidae (penguins)
Genus Eudyptes (rockhopper, macaroni, and related penguins)
Species Eudyptes chrysocome (rockhopper penguin)
Subspecies Eudyptes chrysocome chrysocome
Subspecies Eudyptes chrysocome filholi
Subspecies Eudyptes chrysocome moseleyi

Geographic Range

Rockhopper penguins are found on islands in the southern ocean, such as the Falkland Islands. They occur farther north than many other penguin species.

Biogeographic Regions
neotropical (Native ); atlantic ocean (Native )

Habitat

Rockhopper penguins are found in high grasses called tussocks, where they make burrows and nest. As their name implies, they live on rocky shorelines.

Habitat Regions
temperate ; terrestrial ; saltwater or marine

Terrestrial Biomes
savanna or grassland

Aquatic Biomes
coastal

Physical Description

Range mass
2000 to 3000 g
(70.48 to 105.73 oz)

Average length
55 cm
(21.65 in)

Rockhopper penguins measure about 55 centimeters in length and weigh around 2.5 kilograms. These birds stand upright on two short feet. Their legs are set far back on the body. The waterproof coat, composed of feathers that average 2.9 centimeters in length, is white on the underside and bluish-black on the top. The head has bright yellow plumage on the brow; the yellow feathers extend along the sides. The top of the head has spiked black feathers. The wings are strong, stiff, narrow and flipper-like. Rockhopper penguins have tiny eyes.

Other Physical Features
endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism
sexes alike

Reproduction

Mating calls, which are species specific, are called "ecstatic vocalization." This draws attention to the bird and announces its intentions. Penguins mate with the same partners from previous years. (Williams, 1981)

Mating System
monogamous

 

Breeding interval
Rockhopper penguins breed once yearly.

Range eggs per season
1 to 2

Rockhopper penguins typically mate in the early spring or late summer, enabling the young to go to the sea in the mid-summer. They mate in vast colonies and lay up to two eggs, although sometimes pairs "adopt" a third egg. The first egg is usually 20-50% smaller than second one. The small egg is usually lost, although it is capable of maturing into a normal bird. Adopted eggs are also typically lost. After each egg is laid, it is turned over to the male who sits on it and keeps it in his brood pouch for the next four months until it hatches. (Williams, 1981)

Key Reproductive Features
seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

While the male penguin sits on the incubating egg, he is nourished by the female, or else he fasts for the entire period. If the female does not return with food for the chick once it has hatched, the male produces "penguin's milk" from his digestive system and regurgitates it for the baby.

Parental Investment
precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Protecting: Male); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male)

Lifespan/Longevity

Average lifespan
Status: wild
10 years

The average lifespan of a rockhopper penguin is 10 years.

Behavior

Penguins are very sociable animals. It is very rare to see one alone. Rockhopper penguins are the most aggressive, as well as the most numerous, penguins. They hide their heads under their wing while they rest. Rockhopper penguins leave the breeding colony in late summer or fall and spend 3-5 months at sea, where they find food. Penguin wings are used exclusively for swimming, these sea birds do not fly.

Key Behaviors
natatorial ; diurnal ; territorial ; social ; colonial 

Communication and Perception

Their loud cry, "ecstatic vocalization", is used to announce their presence, attract a mate, or announce the boundaries of their territory. As well as vocalizing, these birds shake their heads and cause their yellow eyebrows to fly into a "halo" in order to attract a mate.

Communication Channels
visual ; acoustic

Food Habits

Rockhopper penguins eat primarily krill (Euphausiacea). They also eat squid and other crustaceans. They make daily trips to the sea to forage.

Primary Diet
carnivore (Eats non-insect arthropods)
Animal Foods
fish; aquatic crustaceans

Economic Importance for Humans: Positive

Penguins are a tourist attraction, and they are one of the main reasons people travel to the Falkland Islands and other habitats of these penguins.

Conservation Status

IUCN Red List of Threatened Species [Link]
Vulnerable

More Information

CITES [Link]

No special status

It is estimated that rockhopper penguins have undergone a decline of more than 30% in their total population size over the past 30 years. For this reason, they are classified as vulnerable by the IUCN. If the decline continues, they may be uplisted to endangered in the near future. Threats to rockhopper penguin populations include commercial fishing, which reduces the amount of available prey, and oil spills. (Bingham, 2002; BirdLife International, 2004; Ryan and Cooper, 1991)

Other Comments

Rockhopper penguins keep warm by their well-developed fat layer and system for maintaining heat.

Contributors

Tanya Dewey (editor), Animal Diversity Web, University of Michigan Museum of Zoology.
Devon Phelan (author), University of Michigan.

References

Gorman, James. 1990. The Total Penguin. Prentice Hall Press, NY.

Grzimek, Dr.Dr.h.c. Bernhard. 1972. Grzimek's Animal Life Encyclopedia. p.133-134. Van Norstrand Reinhold Co. NY.

New Scientist. "Did Warm Water Kill Falkland Penguins?" IPC Magazine Ltd. Vol. 114. May 28, 1987. p.22.

Bingham, M. 2002. The decline of Falkland Islands penguins in the presence of a commercial fishing industry. Revista Chilena de Historia Natural, 75(4): 805-818.

BirdLife International, 2004. "Eudyptes chrysocome" (On-line). 2004 IUCN Red List of Threatened Species. Accessed November 14, 2005 at www.redlist.org.

Ryan, P., J. Cooper. 1991. Rockhopper penguins and other marine life threatened by drift net fisheries at Tristan da Cunha, South Atlantic Ocean. Oryx, 25(2): 76-79.

Williams, A. 1981. The clutch size of macaroni penguins Eudyptes chrysolophus and rockhopper penguins Eudyptes chrysocome. Emu, 81(2): 87. 

 

To cite this page: Phelan, D. 1999. "Eudyptes chrysocome" (On-line), Animal Diversity Web. Accessed May 16, 2012 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Eudyptes_chrysocome.html

 

 Left: Grey morph of the Eastern Screech Owl (Megascops asio). Right: Rufous morph of the Eastern Screech Owl. (Credit: Left: Wolfgang Wander via Wikipedia, Creative Commons license; Right: Greg Hume via Wikipedia, Creative Commons license)

Bird Color Variations Speed Up Evolution

ScienceDaily (May 9, 2012) — Researchers have found that bird species with multiple plumage colour forms within in the same population, evolve into new species faster than those with only one colour form, confirming a 60-year-old evolution theory.

The global study used information from birdwatchers and geneticists accumulated over decades and was conducted by University of Melbourne scientists Dr Devi Stuart-Fox and Dr Andrew Hugall (now based at the Melbourne Museum) and is published in the journal Nature.

The link between having more than one colour variation (colour polymorphism) like the iconic red, black or yellow headed Gouldian finches, and the faster evolution of new species was predicted in the 1950s by famous scientists such as Julian Huxley, but this is the first study to confirm the theory.
By confirming a major theory in evolutionary biology, we are able to understand a lot more about the processes that create biodiversity said Dr Devi Stuart-Fox from the University's Zoology Department.

"We found that in three families of birds of prey, the hawks and eagles, the owls and the nightjars, the presence of multiple colour forms leads to rapid generation of new species," Dr Stuart-Fox said.
"Well known examples of colour polymorphic species in these families include the Australian grey goshawk which has a grey and pure white form, the North American eastern screech owl and the Antillean nighthawk, each with grey and red forms."

The team focused on birds because although colour polymorphism occurs in many animals (such as fish, lizards, butterflies and snails), there is a wealth of information on colour variation in birds, as well as on species classification (taxonomy), partly thanks to birdwatchers or 'twitchers'.
"We looked at five bird families with a high proportion of colour polymorphism and compared their rates of evolution with those with only one colour form," Dr Stuart-Fox said.

By modeling evolutionary rates using publicly available genetic information accumulated over a quarter of a century, the study found that colour polymorphism speeds up the generation of new species. Colour polymorphic species tend to evolve into species with only one colour form (monomorphic), explaining why existing species with different colour forms are relatively young and also rare.

The study found that colour polymorphic species were younger not only in the birds of prey but in the songbirds, which account for more than half of the world's bird species.

Study co-author Dr Andrew Hugall noted that when scientists like Julian Huxley proposed that colour polymorphism speeds up the generation of new species over half a century ago, they did not have the huge amounts of data needed to support it.

"Using many decades of natural history information and 25 years of genetic sequence information we were able to generate the massive family trees, such as a tree of more than four thousand songbirds, needed to model rates of bird evolution in this study," he said.

"Now that we've identified this pattern for the first time, our next step is to test some of the explanations proposed for why colour polymorphism leads to accelerated evolution."

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Story Source:

The above story is reprinted from materials provided by University of Melbourne.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

---

Journal Reference:

1. Andrew F. Hugall, Devi Stuart-Fox. Accelerated speciation in colour-polymorphic birds. Nature, 2012; DOI: 10.1038/nature11050

University of Melbourne (2012, May 9). Bird color variations speed up evolution. ScienceDaily. Retrieved May 11, 2012, from ­source

 

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 **My Note: So does this mean that this explains the lack of speciation in penguins over the millenia?**

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World Penguin Day

Twice as Many Emperor Penguins as Thought in Antarctica, First-Ever Penguin Count from Space Shows

On the ice, emperor penguins with their black and white plumage stand out against the snow and colonies are clearly visible on satellite imagery. (Credit: Paul Ponganis, National Science Foundation)

ScienceDaily (Apr. 13, 2012) — A new study using satellite mapping technology reveals there are twice as many emperor penguins in Antarctica than previously thought. The results provide an important benchmark for monitoring the impact of environmental change on the population of this iconic bird, which breeds in remote areas that are very difficult to study because they often are inaccessible with temperatures as low as -58 degrees Fahrenheit.

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Recently reporting in the journal PLoS ONE, an international team of scientists describe how they used Very High Resolution satellite images to estimate the number of penguins at each colony around the coastline of Antarctica.

Using a technique known as pan-sharpening to increase the resolution of the satellite imagery, the science teams were able to differentiate between birds, ice, shadow and penguin poo or guano. They then used ground counts and aerial photography to calibrate the analysis.

Lead author and geographer Peter Fretwell at British Antarctic Survey (BAS), which is funded by the U.K.'s Natural Environment Research Council, explains, "We are delighted to be able to locate and identify such a large number of emperor penguins. We counted 595,000 birds, which is almost double the previous estimates of 270,000-350,000 birds. This is the first comprehensive census of a species taken from space."

On the ice, emperor penguins with their black and white plumage stand out against the snow and colonies are clearly visible on satellite imagery. This allowed the team to analyze 44 emperor penguin colonies around the coast of Antarctica, and seven previously unknown colonies.
"The methods we used are an enormous step forward in Antarctic ecology because we can conduct research safely and efficiently with little environmental impact, and determine estimates of an entire penguin population, said co-author Michelle LaRue from the University of Minnesota and funded by the U.S. National Science Foundation (NSF).

"The implications of this study are far-reaching: we now have a cost-effective way to apply our methods to other poorly-understood species in the Antarctic, to strengthen on-going field research, and to provide accurate information for international conservation efforts."

NSF manages the U.S. Antarctic Program through which it coordinates all U.S. scientific research on the southernmost continent and aboard ships in the Southern Ocean as well as related logistics support.

Co-author and BAS biologist Phil Trathan noted, "Current research suggests that emperor penguin colonies will be seriously affected by climate change. An accurate continent-wide census that can be easily repeated on a regular basis will help us monitor more accurately the impacts of future change on this iconic species."

Scientists are concerned that in some regions of Antarctica, earlier spring warming is leading to loss of sea ice habitat for emperor penguins, making their northerly colonies more vulnerable to further climate change.

Trathan continued, "Whilst current research leads us to expect important declines in the number of emperor penguins over the next century, the effects of warming around Antarctica are regional and uneven. In the future, we anticipate that the more southerly colonies should remain, making these important sites for further research and protection."

This research is a collaboration between BAS, University of Minnesota/NSF, Scripps Institution of Oceanography and the Australian Antarctic Division.

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Story Source:

The above story is reprinted from materials provided by National Science Foundation.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

---

Journal Reference:

1. Peter T. Fretwell, Michelle A. LaRue, Paul Morin, Gerald L. Kooyman, Barbara Wienecke, Norman Ratcliffe, Adrian J. Fox, Andrew H. Fleming, Claire Porter, Phil N. Trathan. An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space. PLoS ONE, 2012; 7 (4): e33751 DOI: 10.1371/journal.pone.0033751

National Science Foundation (2012, April 13). Twice as many emperor penguins as thought in Antarctica, first-ever penguin count from space shows. ScienceDaily. Retrieved April 14, 2012, from http://www.sciencedaily.com­ /releases/2012/04/120413145303.htm

Endangered Species: Penguins, Ice Caps, and Arctic Monitors

Jason Koebler U.S. News & World Report

April 9, 2012

Scientific stations that track ecological changes increasingly survive on "bare-bones" budgets

The temperatures are warming and the ice is melting--as is the funding for scientific stations that monitor the long-term health of arctic ecosystems.

Measuring melting glaciers and ice caused by global climate change is easy--NASA and NOAA have satellites for that. But measuring the changing climate's impact on local ecosystems is much harder, requiring manned monitoring sites around the world, a much more expensive proposition. With Washington trying to reign in the national budget, the 26 Long Term Ecological Research (or LTER) sites set up around the United States and Antarctica are becoming an increasingly endangered species.

Going forward, "we're funded on a bare-bones basis," says Andrew Fountain, a professor at Portland State University and author of a report released Friday on the importance of sites that measure the ecological impact of ice melts. "We do have funding, but it's always quite limited. I don't think we need another space program to solve this, but having consistent, reliable funding is important for these long-term studies."

The LTER program was created in 1980 by the National Science Foundation--its research is ongoing, but some studies can take decades, especially in polar regions where year-round monitoring can be difficult.

"It has required decades of coordinated observations to document significant change and to uncover the mechanisms linking climate forcing to ecosystem responses," according to Fountain's paper. "The simple logistics of polar regions make them more expensive."

[Read Study: Global Warming is Real]

While the National Science Foundation's budget has remained relatively flat, and even increased by 2.5 percent from 2011 to 2012, some lawmakers have proposed deep cuts to the agency. The journal BioScience had a special section where scientists in LTER outlined some of the discoveries made by these sites, in hopes their importance would be recognized.

Among those findings: Populations of certain penguin species in Antarctica have declined by 80 percent since 1975, wolverines can't breed unless they have sufficient snow to make caves in, and the American pika, a mouse-like creature that lives in the Rocky Mountains, has had its habitat nearly destroyed.

Measuring the environmental impact on disappearing mammal populations isn't too tough, but scientists have reason to believe microbial and krill populations in the polar regions have declined. That creates "cascading upward effects," Fountain says. That may have caused a decline in the penguin population, which can affect larger sea mammals.

[Read Poll: Republicans Coming Around on Global Warming]

"We don't understand really how everything works together--we can't say 'here are the changes, here are the parts of the systems that will change,'" Fountain says. "That's why these long-term ecological sites are important, to maintain monitoring. We need more data."

Charles Driscoll, a Syracuse University professor who studied their importance, said in a statement that LTER sites create "a crucial bridge between the scientific community and society."

"LTER datasets and experiments help inform local- to national-scale decisions regarding climate change, pollution, fire, land conversion, and other pressing environmental challenges," he said.

source

Bus-Size Dinosaurs, Fuzzy as Chicks

Brian Choo

An artist’s impression of Yutyrannus huali, a giant, previously unrecognized dinosaur. The name of the species means “beautiful feathered tyrant.”

By JOHN NOBLE WILFORD

Published: April 4, 2012

Fossils discovered in northeastern China of a giant, previously unrecognized dinosaur show that it is the largest known feathered animal, living or extinct, scientists report.

                                                                           A Yutyrannus skull.

                                                                           Enlarge This Image

                                                                                                                                      Zang Hailong

                                                                    Yutyrannus tail feathers.

Although several species of dinosaurs with feathers have already been uncovered in the rich fossil beds of Liaoning Province, the three largely complete 125-million-year-old specimens are by far the largest. The adult was at least 30 feet long and weighed a ton and a half, about 40 times the heft of Beipiaosaurus, the largest previously known feathered dinosaur. The two juveniles were a mere half ton each. 

The new species was a distant relative of Tyrannosaurus rex, the mighty predator that lived 60 million years later, at the end of the dinosaur era. The scaly T. rex apparently did not go in for feathers. 

In an article in the journal Nature, published online Wednesday, Chinese and Canadian paleontologists said the discovery provided the first “direct evidence for the presence of extensively feathered gigantic dinosaurs” and offered “new insights into early feather evolution.” 

Xing Xu of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, who was the lead author of the paper, said in a statement that it was “possible that feathers were much more widespread, at least among meat-eating dinosaurs, than most scientists would have guessed even a few years ago.” 

Dr. Xu said the feathers were simple filaments, more like the fuzzy down of a modern baby chick than the stiff plumes of an adult bird. Such insubstantial feathers, not to mention the animal’s huge size, would have made flight impossible. The feathers’ most important function was probably as insulation. 

The species has been named Yutyrannus huali, which means “beautiful feathered tyrant” in a combination of Latin and Mandarin. 

Mark A. Norell, a curator of paleontology at the American Museum of Natural History in Manhattan, who had no part in the research, said the findings were significant because they swept aside a longstanding argument that perhaps dinosaurs had feathers only when they were small and shed them as they grew. 

Corwin Sullivan, a Canadian paleontologist affiliated with the Beijing institute and an author of the report, noted that the idea of primitive feathers for insulation was not new. 

“However, large-bodied animals typically can retain heat quite easily, and actually have more of a potential problem with overheating,” Dr. Sullivan said. “That makes Yutyrannus, which is large and downright shaggy, a bit of a surprise.” 

The researchers suggested that the climate might have been cooler when this feathered giant lived than it was when T. rex roamed in the late Cretaceous period. Not necessarily, said Dr. Norell, who pointed out that large, hairy mammals like giraffes and wildebeest, perhaps analogous to feathered dinosaurs, live today in hot latitudes. 

Another possible explanation, offered by the authors of the journal article, is that the feathers were not widely distributed over the dinosaurs’ bodies, and so their function as display plumage cannot be ruled out. Yet the researchers noted several times that the feather covering was extensive and “densely packed,” resembling some recent discoveries of fossil birds “that undoubtedly had plumage covering most of the body.” 

“This is a great time to be a dinosaur paleontologist,” said Dr. Norell, whose research concentrates on fossils from China and the Gobi Desert of Mongolia. “The feathered dinosaurs show how the whole conception of dinosaurs has really changed in the last 15 years.” 

source                                              

Penguin “emissions” acidify air over Antarctic site

22 March 2012

Posted by kramsayer

3

Researchers have identified the source of a spike of atmospheric acidity over an Antarctic site - penguin poop. (Credit: Flickr user Chadica, http://bit.ly/GNl1ku)

After some scientific sleuthing, researchers have tracked down the cause of a mysterious spike in atmospheric acidity over an Antarctic site made famous by the documentary March of the Penguins. The culprit? Penguin poop. It turns out penguins who live in the area could be responsible for acidity levels in December 2010 that were four times higher than levels observed during Southern Hemisphere summers back to 1997.

The Adélie penguins that inhabit the area (think of the wise-cracking group from Happy Feet) produce tons of guano, according to atmospheric scientist Anne-Mathilde Thierry. Literally, their output is about one metric ton (2,205 pounds) per day, explained the Ph.D. student at the Institut Pluridisciplinaire Hubert Curien in Strasbourg, France, and co-author of a new study revealing the unexpected effect of that pronounced penguin production.

The study will be published next week in the Journal of Geophysical Research-Atmospheres, a publication of the American Geophysical Union.

Previous scientific investigations of the atmosphere over this coastal area, known as Dumont d’Urville, have detected releases of oxygenated volatile organic compounds (OVOCs), which cause acidity and which were traced back to natural marine processes in the nearby ocean. However, Michel Legrand of the Laboratoire de Glaciologie et Géophysique de l’Environnement in Grenoble, France, lead author of the new study, and his colleagues found that the compounds, called alkenes, released by the marine processes in December 2010 were insufficient to make up all the OVOCs – and therefore all the acid – present. OVOCs, in general, are easily vaporized chemicals such as acetic acid, acetaldehyde, and acetone. They form through both natural and human-induced processes, including the burning of vegetation, vehicle exhaust, and natural plant emissions, but are short-lived in the atmosphere.

Stumped trying to explain the December OVOC spike, Legrand discussed the puzzle with Thierry. Soon their conversation turned to penguin guano and bacterial activity in the soils that guano eventually becomes. When alkenes released by the decomposing penguin guano were taken into account, the increased levels of acidity made more sense. More alkenes reacting with ozone molecules meant more OVOCs being produced, which would lead to more atmospheric acidity.
Noting that there had been unusually mild weather in December 2010 that sped up decomposition of guano into alkenes, they “started to consider that penguins could have something to do with the increase in atmospheric acidity,” Thierry explained.

“It had to be the penguins! So we took samples of both fresh and old guano so that the chemists could do some more analyses,” she said.

It turns out getting sample supplies of penguin guano for testing was not too difficult. “When you study penguins, you tend to get guano on your clothes during a typical day of work – so it wasn’t much of a trouble to get the fresh guano samples,” Thierry said.

While the acidity over Dumont d’Urville was remarkable enough to prompt a scientific investigation, it isn’t enough to set off environmental or ecological alarms, Legrand said.

Large amounts of OVOCs can affect the atmosphere’s ability to cleanse itself, but the increased quantities of acids in this case are too small to cause harm. “At the local scale, the high concentrations of acetic acid make this acid dominant compared to other acidic species,” noted Legrand. Yet, “I don’t think the species emitted by penguin colonies have a significant detrimental effect,” he added.

For a break from the science of it, check out Sea World San Diego’s penguin cam.

Legrand, M., Gros, V., Preunkert, S., Sarda-Estève, R., Thierry, A., Pepy, G., & Jourdain, B. (2012). A reassessment of the budget of formic and acetic acids in the boundary layer at Dumont d’Urville (coastal Antarctica): The role of penguin emissions on the budget of several oxygenated volatile organic compounds Journal of Geophysical Research DOI: 10.1029/2011JD017102

Warming Antarctic Brings Changes to Penguin Breeding Cycles

Chinstrap penguins at Bailey Head, Deception Island in the Antarctic Peninsula. (Credit: Photograph by Ron Naveen ©2011)

 

ScienceDaily (Mar. 21, 2012) — Three penguin species that share the Western Antarctic Peninsula for breeding grounds have been affected in different ways by the higher temperatures brought on by global warming, according to Stony Brook University Ecology and Evolution Assistant Professor Heather Lynch and colleagues. The work by Lynch and her team is contained in three papers that have been published online in Polar Biology, Ecology and Marine Ecology Progress Series (MEPS).

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Lynch and her colleagues used a combination of field work and, increasingly, satellite imagery to track colonies of three penguin species -- Adélie, chinstrap and gentoo. The Adélie and chinstrap migrate to the peninsula to breed, while the gentoo are year-round residents.

The Antarctic is considered one of the world's most rapidly warming regions. Warmer temperatures move up the breeding cycle, causing the penguins to lay their eggs earlier. The resident gentoo population is able to adapt more quickly and advance their "clutch initiation" by almost twice as much as the other species. Lynch believes this may allow them to better compete for the best nesting space. The Adélie and chinstrap are unaware of the local conditions until they arrive to breed and have not been able to advance their breeding cycles as rapidly.

In addition, the gentoo prefer areas with less sea ice, and have been able to migrate further south into the Antarctic as the sea ice shrinks. The chinstrap and Adélie species rely more heavily on the abundance of Antarctic krill, which require sea ice for their lifecycle.

The result -- the gentoo numbers are increasing while the other two species have noticeably dwindling populations on the Antarctic Peninsula.

Professor Lynch will speak about her research and advances in the use of satellite imagery to track penguin populations as part of "Polar Climate Change Research: A Workshop for Educators" at the Charles B. Wang Center at Stony Brook University on April 10-11, 2012. The workshop, sponsored by the joint BNL-SBU Center for Impacts of Regional Climate Change (CIRCC), is designed to give high school science teachers the tools they need to teach about climate change in the Polar regions.

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Story Source:

The above story is reprinted from materials provided by Stony Brook University, via Newswise.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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Journal References:

1. Heather J. Lynch, Ron Naveen, Philip N. Trathan, William F. Fagan. Spatially integrated assessment reveals widespread changes in penguin populations on the Antarctic Peninsula. Ecology, 2012; : 120117073021007 DOI: 10.1890/11-1588.1
2. HJ Lynch, WF Fagan, R Naveen, SG Trivelpiece, WZ Trivelpiece. Differential advancement of breeding phenology in response to climate may alter staggered breeding among sympatric pygoscelid penguins. Marine Ecology Progress Series, 2011; DOI: 10.3354/meps09252
3. Heather J. Lynch, Richard White, Andrew D. Black, Ron Naveen. Detection, differentiation, and abundance estimation of penguin species by high-resolution satellite imagery. Polar Biology, 2012; DOI: 10.1007/s00300-011-1138-3

Stony Brook University (2012, March 21). Warming Antarctic brings changes to penguin breeding cycles. ScienceDaily. Retrieved March 22, 2012, from source

Iridescent, Feathered Dinosaur Offers Fresh Evidence That Feathers Evolved to Attract Mates

Microraptor fossil. (Credit: Image courtesy of University of Texas at Austin)

ScienceDaily (Mar. 8, 2012) — A team of American and Chinese researchers has revealed the detailed feather pattern and color of Microraptor, a pigeon-sized, four-winged dinosaur that lived about 120 million years ago. A new specimen shows the dinosaur had a glossy iridescent sheen and that its tail was narrow and adorned with a pair of streamer feathers, suggesting the importance of display in the early evolution of feathers, as presented in the March 9 edition of the journal Science.

The research was conducted by scientists at the Beijing Museum of Natural History, Peking University, The University of Texas at Austin, the University of Akron, and the American Museum of Natural History.

By comparing the patterns of pigment-containing organelles from a Microraptor fossil with those in modern birds, the scientists determined the dinosaur's plumage was iridescent with a glossy sheen like the feathers of a crow. The new fossil is the earliest record of iridescent color in feathers.
A new reconstruction of the dinosaur will help scientists approach the controversy of how dinosaurs began the transition to flight.

Since it was discovered as the first four-winged dinosaur in 2003, Microraptor has been at the center of questions about the evolution of feathers and flight. A number of scientists have proposed aerodynamic functions for various feathery features such as its tail, forewing shape and hind limbs, going so far as to place Microraptor models in wind tunnels and launch them from catapults. Once thought to be a broad, teardrop-shaped surface or with a shape more like that of a paper airplane meant to help generate lift, Microraptor's tail fan is actually much narrower with two elongate feathers off of its tip. The researchers believe the tail feathering may have been ornamental and probably evolved for courtship and other social interactions and not as an adaptation for flight.
"Most aspects of early dinosaur feathering continue to be interpreted as fundamentally aerodynamic, optimized for some aspect of aerial locomotion," said Julia Clarke, one of the paper's co-authors and an associate professor of paleontology at The University of Texas at Austin's Jackson School of Geosciences. "Some of these structures were clearly ancestral characteristics that arose for other functions and stuck around, while others may be linked to display behaviors or signaling of mate quality. Feather features were surely shaped by early locomotor styles. But, as any birder will tell you, feather colors and shapes may also be tied with complex behavioral repertoires and, if anything, may be costly in terms of aerodynamics."

"Modern birds use their feathers for many different things, ranging from flight to thermoregulation to mate-attracting displays," said Matt Shawkey, a co-author and associate professor of biology at the University of Akron. "Iridescence is widespread in modern birds and is frequently used in displays. Our evidence that Microraptor was largely iridescent thus suggests that feathers were important for display even relatively early in their evolution."

The scientists deduced Microraptor was iridescent when Shawkey discovered that in the most common iridescent feathers, arrays of pigment-bearing organelles called melanosomes were uniquely narrow.

Information on feather color of a variety of dinosaurs has recently come to light, since the first color map of an extinct dinosaur showed black and white spangles, red coloration and gray body color in a species called Anchiornis in 2010. Based on the new data from Microraptor and these other finds, a complex color repertoire that includes iridescence is probably ancestral to a group of dinosaurs called Paraves that originated at least 140 million years ago and includes dinosaurs such as Velociraptor as well as Archaeopteryx, Anchiornis and living birds.

"This study gives us an unprecedented glimpse at what this animal looked like when it was alive," said Mark Norell, co-author and chair of the American Museum of Natural History's Division of Paleontology. Clarke, Norell and the AMNH team, also including Mick Ellison and Rui Pei, worked closely re-analyzing the bony anatomy and digital overlays of the feathering in the new specimen and eight previously described Microraptor specimens to come up with their new view of the animal.
The researchers studied feathering, melanosome shape and density from a Microraptor fossil working closely with collaborators Quanguo Li, Ke-Qin Gao and Meng Qingjin at the Beijing Museum of Natural History. The samples and preservation of melanosomes were assessed by Jakob Vinther and compared with a database of melanosomes from a variety of modern birds assembled by Shawkey and Liliana D'Alba at the University of Akron.

The feather color displayed by many modern birds is produced partially by arrays of melanosomes, about a hundred of which can fit across a human hair. Generally found in a round or cigar-like shape, a melanosome's structure is constant for a given color. After a breakthrough by Vinther in 2009, paleontologists have started analyzing the shape of melanosomes in well-preserved fossilized feather imprints. By comparing these patterns with those in living birds, scientists can infer the color of dinosaurs that lived many millions of years ago. Iridescence arises when the narrow melanosomes are organized in stacked layers.

The research was funded by the National Science Foundation, the Air Force Office of Scientific Research, the Natural Science Foundation of China, the Beijing Municipal Bureau of Human Resources, and the Beijing Academy of Science and Technology.

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Story Source:

The above story is reprinted from materials provided by University of Texas at Austin.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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Journal Reference:

1. Q. Li, K.-Q. Gao, Q. Meng, J. A. Clarke, M. D. Shawkey, L. D'Alba, R. Pei, M. Ellison, M. A. Norell, J. Vinther. Reconstruction of Microraptor and the Evolution of Iridescent Plumage. Science, 2012; 335 (6073): 1215 DOI: 10.1126/science.1213780

University of Texas at Austin (2012, March 8). Iridescent, feathered dinosaur offers fresh evidence that feathers evolved to attract mates. ScienceDaily. Retrieved March 9, 2012, from ­http://www.sciencedaily.com­ /releases/2012/03/120308143159.htm

Iridescent, Feathered Dinosaur Offers Fresh Evidence That Feathers Evolved to Attract Mates

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Penguins' food goes south

Posted on: 03 Mar 2012

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Climate change warming the sea surface is separating breeding King Penguins from their main food sources, a new study shows.

King Penguins are the top avian fish consumers in the southern oceans, and their feeding ranges, habits and behaviour have been widely studied in this context for decades. However, overall seabird populations in the Antarctic's catchment have been changing for at least the last three decades and demographic modelling suggests that there will be radical changes over the next 100 years. The polar regions have been warming at a  faster rate than more temperate and tropical areas, and most scientific predictions are that this will continue over the rest of the century.

The Crozet Islands' King Penguins number well over one million individuals, far and away the largest population in the world and not currently viewed as being under any conservation threat. The population has been studied fairly comprehensively since the early 1960s and, though the population increased up to the 1990s, since 1994 there has been a notable decline. A particular long-term breeding dataset from Possession Islands in the archipelago was used to understand and model the habitat the penguins use during incubation and brooding, and to predict how the warming of the southern oceans would affect the distribution of this habitat, so important for the penguins continued survival.

The study's data confirmed that sea surface temperature controls the areas that are productive for King Penguin foraging during incubation and brooding, and that the penguins mostly use the colder pelagic waters of the polar air mass front, tracking these as they fluctuate between 300-500 km south of their colony. Models derived from the long-term data predict that the optimum feeding zones will shift south by about 400 km by 2100, and that therefore feeding during the early stages of the breeding cycle will become a significant challenge in the near future.

Clearly, the penguins reliance on the fish species that congregate around the polar front will mean that birds already under pressure from breeding will have to expend more energy swimming further  to collect more food over a shorter time period, a handicap compounded as the front moves gradually southwards over the course of the summer, anyway.

Demographic studies already indicate that breeding success declines during warmer summers in the Crozet Islands, but this may not necessarily be the case at other on Kerguelen and Heard islands, which are not as affected by the warming surface temperatures due to the shallower seas around them reducing the amount of annual temperature variation. Also, not enough is known about the responses of the major fish prey species involved to the changing surface temperatures to fully predict their movements, though fish have certainly changed their distribution in other parts of the world because of this.

However, the 21st century is not looking good for the Crozet Island populations unless they are able to evolve new foraging strategies or move to alternative breeding sites over time.

Reference
Péron, C, Weimerskirch, H and Bost, C-A. 2012. Projected poleward shift of king penguins (Aptenodytes patagonicus) foraging range at the Crozet Islands, southern Indian Ocean. Proceedings of the Royal Society B: doi: 10.1098/rspb.2011.2705.

from BirdWatch 

Penguin fossils offer 'chance of a lifetime'

ROSA STUDHOLME

 03/03/2012

The scientist behind the exciting discovery of two unknown species of penguin in the Waitaki Valley says the area provides unique fossils that help bring history to life.

A report published this week by Daniel Ksepka, of North Carolina State University, has revealed previously unknown fossilised species Kairuku Grebneffi and Kairuku Waitaki, that were discovered in the Waitaki 20 years ago.

The revelation has caused excitement in the international science community.
More remarkable is the penguins are believed to have stood 1.3m tall – 30cm taller than their nearest modern-day descendant, the emperor penguin, of Antarctica.

It weighed at least 60kg, which is 50 per cent heavier than the emperor.

Otago University geology professor Ewan Fordyce first came across the fossilised bones in a cliff in the Waihao Valley near Waimate in 1977 while on a field trip looking for whale and dolphin fossils.
He was a PhD student at the time.
"It was the broken end of a leg bone and I thought, `that looks different'.

"Then I realised the species was bigger than expected. We knew this was something big.
"We've had a succession of other finds since then," he said.

The latest was last December with discoveries in the Duntroon area.

The well-preserved fossils allowed scientists to rebuild the bird and form a "clear description".
"I thought we really should bring in one of the leading people [so in 2009] I invited Dr Ksepka to come over here and work with me on the material."

Dr Ksepka was able to help in rebuilding the fossils.

Students at the university had also helped with the project for their theses.
Dr Fordyce said the Waitaki Valley was ideal for excavating fossils as the limestone geology of the area aided preservation.
Remains of large penguins had been found in other areas of New Zealand and overseas but were not as complete as the fossils found in the Waitaki Valley.

It was "very, very satisfying" to have been part of the discovery, he said.
"It tells us that penguins were different in the past.

"Why were they bigger and why did they disappear? As far as why they disappeared we really don't know.

"It could have been, for example, climate change. It could have been the appearance of some new predator. There are a variety of options.

"Those questions that we can't easily answer, they're the thing that drives our research."
He said the large size of the seabird would have meant it could swim further and dive deeper than modern penguin species.

At least four individual Kairuku penguins are known. The fossils recovered from the Waitaki Valley are now displayed in the Geology Museum.

Remains of "giant" penguins were first recovered from New Zealand as long ago as the 1840s, but there were no reasonably complete specimens.

Dr Fordyce said the finds were very exciting for penguin biologists and provided a significant boost to what was known internationally about the history of penguins.

Finding such specimens offered the "chance of a lifetime" to better understand extinct penguins that lived before the earliest fossils of modern species more than 15 million years ago.
 
"For the first time we have been able to publish really clear evidence about the body size and proportions of these older penguins."

The diversity of species and the penguin's unique physique had made the reconstruction difficult.
"Kairuku was an elegant bird by penguin standards, with a slender body and long flippers, but short, thick legs and feet," Dr Ksepka said.

The researchers rebuilt size and proportions from two main fossils, using the skeleton of an existing king penguin as a model.

Dr Ksepka hoped that the rebuilding of Kairuku would give other palaentologists more information about other fossils found in that area, as well as add to the knowledge about giant penguin species.
- © Fairfax NZ News
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