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Friday, January 30, 2009
Wednesday, January 28, 2009
Emperors March Toward Extinction?
Science News
Emperor Penguins March Toward Extinction?
ScienceDaily (Jan. 27, 2009) — Popularized by the 2005 movie “March of the Penguins,” emperor penguins could be headed toward extinction in at least part of their range before the end of the century, according to a paper by Woods Hole Oceanographic Institution (WHOI) researchers published in Proceedings of the National Academy of Sciences of the United States of America.
The paper, co-authored by five researchers including WHOI biologists Stephanie Jenouvrier and Hal Caswell, uses mathematical models to predict the effect on penguins of climate change and the resulting loss of sea ice.
The research indicates that if climate change continues to melt sea ice at the rates published in the latest Intergovernmental Panel on Climate Change (IPCC), the median population size of a large emperor penguin colony in Terre Adelie, Antarctica, likely will shrink from its present size of 3,000 to only 400 breeding pairs by the end of the century.
What’s more, the researchers calculate that the probability of a drastic decline (by 95 percent or more) is at least 40 percent and perhaps as much as 80 percent.
Such a decline would put the population at serious risk of extinction.
“The key to the analysis was deciding to focus not on average climate conditions, but on fluctuations that occasionally reduce the amount of available sea ice,” said Hal Caswell, who is noted for his work in mathematical ecology.
Sea ice plays a critical role in the Antarctic ecosystem – not only as a platform for penguins to breed, feed, and molt, but as a grazing ground for krill, tiny crustaceans that thrive on algae growing on the underside of the ice. Krill, in turn, are a food source for fish, seals, whales, and penguins.
One fluctuation and subsequent sea ice reduction in Terre Adelie during the 1970s led to a population decline in emperor penguins of about 50 percent.
The team led by Caswell and Jenouvrier developed a series of models to incorporate the effect of the fluctuations on the penguin life history and population growth or decline. The models used data collected by French scientists working in Terre Adelie beginning in the 1960s. Then, working with climate scientists, Jenouvrier, Caswell and their colleagues looked at IPCC climate models and found that these fluctuations are likely to become much more frequent as the climate changes over the next 100 years.
Because Jenouvrier and Caswell’s models were based on fluctuations rather than smooth trends, and because different IPCC models differ in their forecasts of future Antarctic climate, the results of the analysis incorporate uncertainty in the details of the future population growth, but the conclusions are not uncertain. “If the future behaves anything like the IPCC models predict, the Terre Adelie population will decline, probably dramatically,” said Jenouvrier
Certain predictions even suggested that the geographic range of Antarctic penguins may shrink following climate warming because the continent limits their movement south. Over the last 50 years, climate change has been most pronounced in the Antarctic Peninsula, where Terre Adelie is located. In the future, the Ross Sea—where sea ice actually has increased in recent years—may be the last sanctuary for penguins.
The WHOI research raises several questions for Antarctic researchers and those interested in conservation of penguins. One is what the march of this population toward extinction tells us about the prospects for the emperor penguin throughout its range. “This analysis focuses on a single population—that at Terre Adelie—because of the excellent data available for it. But patterns of climate change and sea ice in the Antarctic are an area of intense research interest now. It remains to be seen how these changes will affect the entire species throughout Antarctica,” said Caswell.
Another is the mechanism by which changes in sea ice affect the penguins. “The mechanisms are complex, and are an active area of research,” added Jenouvrier.
Yet another question is whether the penguins might adapt to changing conditions, perhaps by changing the timing of their breeding cycle. However, this does not seem to be happening. “Unlike some other Antarctic bird species that have altered their life cycles, penguins don’t catch on so quickly,” Jenouvrier said. “They are long-lived organisms, so they adapt slowly. This is a problem because the climate is changing very fast.”
The research was a collaboration between the mathematical ecology group at WHOI, led by Caswell, a group of French scientists from Expeditions Polaires Francaises and Institut Paul Emile Victor, and climate scientists from the National Center for Atmospheric Research and the National Snow and Ice Data Center. “The project was truly interdisciplinary,” said Jenouvrier, “which is critical for this kind of research.”
In the more immediate future, the study even might impact legal protections available for the emperor penguin. In December, the U.S. Fish and Wildlife Service issued a preliminary ruling declining to list the emperor penguin under the Endangered Species Act. Caswell said this ruling is still being evaluated and research presented in this paper will have to be considered.
He added that species threatened by climate change are among the most difficult conservation problems. Improving the situation will require global actions to address a truly global environmental problem.
Support for this work was provided by the UNESCO/L'OREAL Women in Science program and the National Science Foundation.
Journal reference:
1. Jenouvrier et al. Demographic models and IPCC climate projections predict the decline of an emperor penguin population. Proceedings of the National Academy of Sciences, Jan 26, 2009; DOI: 10.1073/pnas.0806638106 (Download HERE)
Adapted from materials provided by Woods Hole Oceanographic Institution.
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MLA
Woods Hole Oceanographic Institution. "Emperor Penguins March Toward Extinction?." ScienceDaily 27 January 2009. 28 January 2009 .
Tuesday, January 27, 2009
Larger Brain Size Saved Birds from Last Major Extinction Event
Birds Survived Mass Extinction That Wiped Out Dinosaurs Because Of Their Larger Brains
CT scan of skull of ancient seabird - the brain is shown in blue and the inner ear in red. (Credit: Image courtesy of Natural History Museum, London)
ScienceDaily (Jan. 27, 2009) — The Cretaceous–Tertiary mass extinction 65 million years ago may have wiped out the dinosaurs, but those that survived – the ancestors of today's birds – may have done so because of their bird brains.
Analysis of computer tomography (CT) scans of fossilised bird skulls shows they had a more developed, larger brain than previously thought.
'Birds today are the direct descendents of the Cretaceous extinction survivors, and they went on to become one of the most successful and diverse groups on the planet,' says Natural History Museum palaeontologist (fossil expert), Dr Stig Walsh.
'There were other flying animals around, such as pterosaurs and older groups of birds,' says Dr Walsh, 'but we've not really known why the ancestors of the birds we see today survived the extinction event and the others did not. It has been a great puzzle for us – until now.'
A larger and more complex brain may have given them a competitive advantage over the other more ancient birds and pterosaurs, helping them to better adapt when the environment changed after the mass extinction event.
Larger brains in living birds
Species of living birds that have larger brains are more likely to live in more socially complex groups and exhibit more complex and flexible behaviour than those with smaller brains.
For instance, members of the crow family have large brains, and some make and use tools, inventing cunning ways to find food.
Previous research has suggested birds with larger brains are more likely to survive if introduced to new environments than those with smaller brains.
These results suggest that this kind of behavioural flexibility was already a characteristic of the ancestors of modern birds before the Cretaceous–Tertiary extinction event.
Surviving the aftermath
'In the aftermath of the extinction event, life must have been especially challenging,' says Dr Walsh.
'Birds that were not able to adapt to rapidly changing environments and food availability did not survive, whereas the flexible behaviour of the large-brained individuals would have allowed them to think their way around the problem.'
Fossil skulls from Isle of Sheppey
The team studied 2 fossil seabirds, found in the London Clay Formation on the Isle of Sheppey in England.
These deposits are famous for the huge range of preserved fossils, from molluscs, fishes, birds and even mammals.
These ancient creatures lived in the warm, semi-tropical conditions of southern England 55 million years ago.
CT scans of seabirds
Natural History Museum palaeontologist and team leader, Dr Angela Milner explains how they worked out the brain size. 'The shape of the brain is imprinted on the inside of the braincase of birds and represents a reasonably accurate approximation of the original shape and volume of the brain'.
'Using CT analysis, we were able to create a virtual cast of this cavity so that the shape and detail of the brain and its nerves could be analysed.' You can see a virtual cast of a crow at the top of the page.
Ancient seabirds
Odontopteryx toliapica belonged to an extinct group of large, gliding seabirds called Odontopterygiformes, or bony-toothed birds. The largest had a wing span of up to 7m.
Prophaethon shrubsolei was an extinct relative of the modern tropic birds that live in tropical areas around the world.
Unexpected results
'We did not expect the brains of Odontopteryx toliapica and Prophaethon shrubsolei to be so much like those of living birds,' says Dr Walsh.
'The brain of the oldest-known flying bird, Archaeopteryx, is very bird-like, but not as large as in the fossil seabirds or living bird species.'
'The parts of the brain that control sight, flight and high-level functions, including the ability to learn and remember information, turned out to be every bit as expanded in the 55-million-year-old fossils as they are in living species.'
'This proves that the avian brain was already rather modern in appearance and organisation.'
This research is published in the Linnean Society's Zoological Journal of the Linnean Society
Adapted from materials provided by Natural History Museum, London.
Story courtesy of Science Daily @
http://www.sciencedaily.com/releases/2009/01/090127165505.htm
Special thanks to Krissa in CA, USA for the heads up on this article.
Monday, January 26, 2009
Pygoscelis papua
Facts
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Pygoscelis (1)
Size Height: 73 – 81 cm (2)
Male weight: 4.9 – 8.5 kg (3)
Female weight: 4.5 – 8.2 kg (3)
Status
Classified as Near Threatened (NT) on the IUCN Red List 2007 (1).
Description
This charismatic marine bird is easily distinguished from other penguins by its bright orange-red bill and the conspicuous white patches above each eye (3). These white patches, which usually meet across the crown, contrast highly with the black head and throat, but there may also be a scattering of white feathers on the head. The white underparts are sharply separated from the penguin's bluish-black back, which appears browner as the feathers become worn (3). The gentoo penguin has pale whitish-pink webbed feet and a fairly long tail - the most prominent tail of all penguins (2) (3) (4). As the gentoo penguin waddles along on land, its tail sticks out behind, sweeping from side to side, hence the scientific name Pygoscelis, which means ‘brush-tailed' (4). The gentoo penguin calls in a variety of ways, but the most frequently heard is a loud trumpeting which is emitted with its head thrown back (5).
Range
The gentoo penguin has a circumpolar distribution, breeding on sub-Antarctic Islands and the Antarctic peninsula (3). Two subspecies of the gentoo penguin are recognised (2): Pygoscelis papua papua breeds mainly on the Falkland Islands and South Georgia, Kerugulen, Heard, Macquarie and Staten Islands, while Pygoscelis papua ellsworthi breeds on the Antarctic Peninsula, South Shetland Island, South Orkney and South Sandwich Island (3). The gentoo's non-breeding range is not fully known, but they have been found as far north as New Zealand, Australia and Argentina (3).
Habitat
This marine bird can be found searching for food in inshore waters (2). When breeding, the gentoo penguin favours flat ground (2), either close to the coast or a considerable distance inland (3), where it nests in rocky areas, sometimes amongst vegetation (2).
Biology
A gregarious bird, but less so than some other penguin species (2), the gentoo can form breeding colonies ranging from thirty to thousands of pairs (5). Arriving at suitable nesting ground between June and November (the exact date depending on the location) (2), each pair of penguins will set about the task of constructing a nest from stones, tussock grass and moss (2). The penguins tear up plants to use as nest material and fertilise the ground with their droppings, resulting in grass growing well the subsequent year, hence their favourable reputation with sheep farmers (5).
Into these nests two white, spherical eggs are laid, which are incubated by both the male and female for 31 to 39 days (2). The penguin chicks fledge after 85 to 117 days, but continue to be fed by their parents for a further 5 to 50 days. Gentoo penguins, which reach sexual maturity at the age of two years (2), are not only faithful to certain nest sites, with most returning to the previous year's nest, but they are also loyal to breeding partners, with many forming long-lasting pair bonds (3).
Walking with a rather comedic, waddling gait on land, the gentoo penguin shows its true talents when in the water. With its stream-lined body and ‘flippers' that provide effective propulsion through the water (6), the gentoo penguin dives deep into the ocean in pursuit of its prey, and is capable of reaching impressive depths of up to 170 metres (3). The exact diet of the gentoo penguin varies depending on location, but can include Atlantic krill, other crustaceans, fish, cephalopods and polychaetes (2).
Threats
Although not globally threatened with extinction, some gentoo penguin colonies have declined (1). While those on the Antarctic Peninsula appear to be increasing overall, populations on sub-Antarctic islands may have decreased considerably (1). For example, populations on Bird Island (South Georgia) have decreased by around 67 percent since 1980 (1). In the past, some colonies were affected by the collection of eggs for human consumption and the hunting of adults for their oil (2). Today, possible reasons behind population declines include local pollution, interaction with fisheries, and disturbance by humans (1); colonies on Kerguelen Island and Possession Island are said to have been disturbed by the presence of scientific bases (2).
Conservation
The gentoo penguin breeds in a number of protected areas, including MacQuarie Island and Heard Island, which are both Natural World Heritage Sites (7), and Prince Edward Islands Special Nature Reserve (8). To prevent the charming gentoo becoming threatened with extinction, the global bird conservation organization BirdLife International have recommended that efforts need to be made to avoid any disturbance of breeding colonies, and that colonies should be subject to long-term monitoring (8).
Further Information
For further information on the conservation of penguins see:
* International Penguin Conservation Work Group:
www.penguins.cl
References
1. IUCN Red List (June, 2008)
http://www.iucnredlist.org
2. del Hoyo, J., Elliott, A. and Sargatal, J. (1992) Handbook of the Birds of the World. Volume 1: Ostrich to Ducks. Lynx Edicions, Barcelona.
3. Williams, T.D. (1995) Bird Families of the World: The Penguins. Oxford University Press, Oxford.
4. British Antarctic Survey (June, 2008)
http://www.antarctica.ac.uk/about_antarctica/wildlife/birds/penguins/gentoo.php
5. Woods, R.W. (1975) The Birds of the Falkland Islands. Anthony Nelson, Shropshire, UK.
6. Burnie, D. (2001) Animal. Dorling Kindersley, London.
7. World Database on Protected Areas (July, 2008)
http://www.unep-wcmc.org/wdpa
8. BirdLife International (July, 2008)
http://www.birdlife.org/datazone/species/index.html?action=SitHTMDetails.asp&sid=7176&m=0
Info courtesy of ARKive@
http://www.arkive.org/gentoo-penguin/pygoscelis-papua/info.html
Pix from Flickr
Sunday, January 25, 2009
Friday Videos (yes, it's Sunday-sigh!)
wiinterrr
Saturday, January 24, 2009
Tuesday, January 20, 2009
Images This Week--Virtual Tour of NZ Penguin Attractions
The Center is home to the New Zealand, United States and Italian Antarctic Programs and comprises administration offices, warehousing, a US & NZ clothing store, a post office and travel agency, the Antarctic Passenger Terminal and of course the Visitor Center, now known as 'The Antarctic Attraction'. The center operates a Hagglund Ride around the center's land. This is aimed mainly at children, however is an educational tool for all ages, to display the mobility of the Hagglund. The Hagglund is an Antarctic Vehicle that is still in operation. Among other attractions, there is an Antarctic snow storm room, an audiovisual, and little blue penguins at the NZ Penguin Encounter..
It is a well known tourist attraction, just a few minutes walk from the airport, with a cafe and bar.
The staff at the center also offers an educational program for groups and individuals on Antarctica and the Little Blue Penguin.
You can even watch the Little Penguins at feeding time, but check for that time as soon as you arrive, as the time may change from one day to the next.
The Little Blue Penguin display is also home to rehabilitated birds who can no longer live in the wild. Yet, here they have the opportunity to live out their lives as normally as possible. Note the little guy carrying nest material. :)
When you buy a Penguin Backstage Pass ticket you will experience an additional and exclusive tour of our 'behind the scenes' areas in the NZ Penguin Encounter.
Limited to just 8 visitors per tour, the Penguin Backstage Pass takes you into the areas not accessible to visitors, hosted by one of our Antarctic Rangers. See how our quarantine area works, learn about penguin feeding and husbandry and take your penguin knowledge to the next level!
Bookings are essential for the daily tours at 11.00am, 2.00pm and 3.00pm. Tickets are just $20.00(Please note that entry ticket must be purchased first).
And don't take my word for it--look for yourself HERE
Many thanks to
http://on-walkabout.com/2009/01/14/walkabout-international-antarctic-centre/
http://en.wikipedia.org/wiki/International_Antarctic_Centre
http://www.iceberg.co.nz/
... for information and images,
and Flickr for the images
Monday, January 19, 2009
New Info on Hearing, Behavior Of Oldest Fossil Bird
Science News
High-tech Imaging Of Inner Ear Sheds Light On Hearing, Behavior Of Oldest Fossil Bird
ScienceDaily (Jan. 14, 2009) — The earliest known bird, the magpie-sized Archaeopteryx, had a similar hearing range to the modern emu, which suggests that the 145 million-year-old creature — despite its reptilian teeth and long tail — was more birdlike than reptilian, according to new research.
Using innovative modern technology, a team of paleontologists and biologists from London, Munich and Ohio have shown for the first time how the length of the inner ear of birds and reptiles can be used to accurately predict their hearing ability and even aspects of their behavior.
"In modern living reptiles and birds we found that the length of the bony canal containing the sensory tissue of the inner ear is strongly related to their hearing ability," said study co-author Paul Barrett, a palaeontologist at London's Natural History Museum. "We were then able to use these results to predict how extinct birds and reptiles may have heard and found that Archaeopteryx had an average hearing range of approximately 2000 Hz. This means it had similar hearing to modern emus, which have some of the most limited hearing ranges of modern birds."
Researchers previously have only been able to estimate how prehistoric animals heard by examining the skulls of damaged fossils and relating brain region size to hearing ability, based on comparisons to the animals' modern relatives. Computed tomography or CT imaging, however, allowed the team to accurately reconstruct the inner ear anatomy of various intact bird and reptile specimens. Fifty-nine species were studied, including turtles, crocodiles, snakes and birds.
"By examining the three dimensional CT scans we were able to see for the first time the real relationship between hearing ability and behavior in extinct reptiles and birds," said Stig Walsh, Natural History Museum palaeontologist and lead author on the study. "The size of the cochlea duct (the bony part of the inner ear housing the hearing organ) in living birds and reptiles accurately predicts the hearing ranges of these animals. This simple measurement can therefore provide a direct means for determining hearing capabilities, and possibly behavior, in their extinct relatives, including Archaeopteryx."
The study, published in the latest issue of the journal Proceedings of the Royal Society B, also adds more information about how bird-like Archaeopteryx was, said Angela Milner, also from the Natural History Museum. "Our previous research has shown that the part of the ear that controls balance was just like that of modern birds, and now we know that Archaeopteryx had bird-like hearing too," she said.
Other team members included Geoff Manley from the Technical University of Munich, who is a leading scientist in the study of hearing in modern animals, and Lawrence Witmer of Ohio University's College of Osteopathic Medicine in Athens, Ohio. Witmer has studied the structure of the brain and inner ear in dozens of species of dinosaurs and modern and extinct birds, including Archaeopteryx.
"This delicate little inner ear has only recently become a player for those of us trying to interpret the past, because it's buried deep within the skull," said Witmer, whose research is funded by the National Science Foundation. "Thanks to CT scanning, we can now get a clear picture of its structure. It's turned out to be a pretty useful organ for deciphering the lives of extinct animals. My previous research has shown that inner ear structure also can tell us about eye movements, head posture, agility, and the relative importance of hearing, and this new study now shows that this sensory Swiss-army knife can tell us about sociality, vocal complexity and maybe even habitat preference."
Animals with a long cochlear duct tended to have the best hearing and vocal ability. Modern living bird species are known to possess relatively longer cochlear ducts than living reptiles. A long cochlear duct is also an indicator of an individual's complex vocal communication, living in groups and even habitat choice. This is true for both mammals and birds.
"Species that form large social groups have more complicated vocal communication, which is understandably influenced by an individual's ability to hear. Species living in a closed environment where visual communication is ineffective often posses more complex vocal abilities, so now we can more accurately predict the habitat types that extinct animals lived in by examining their ability to hear and communicate," Barrett said.
The research received funding from the Natural Environment Research Council and the National Science Foundation.
Ohio University. "High-tech Imaging Of Inner Ear Sheds Light On Hearing, Behavior Of Oldest Fossil Bird." ScienceDaily 14 January 2009. 19 January 2009
Sunday, January 18, 2009
Eudyptes moseleyi --Will We Allow the Northern Rockhopper to Become Extinct?
Penguins are walking an increasingly rocky road
16-01-2009
A new study, published in BirdLife International’s journal, Bird Conservation International, has revealed that the Northern Rockhopper Penguin Eudyptes moseleyi – which is principally found on UK territories in the South Atlantic – has declined by 90% over the last 50 years [1].
Historical records estimate that millions of penguins used to occur on Tristan da Cunha and Gough Island, but, declines (of more than 90%) have dramatically reduced their numbers in the last half century.
"Historically, we know that penguins were exploited by people, and that wild dogs and pigs probably had an impact on their numbers. However, these factors cannot explain the staggering declines since the 1950s, when we have lost upwards of a million birds from Gough and Tristan. The declines at Gough since the 1950s are equivalent to losing 100 birds every day for the last 50 years", said Richard Cuthbert of the RSPB (BirdLife in the UK) and lead author of the paper. "With more than half the world’s penguins facing varying degrees of extinction, it is imperative that we establish the exact reason why the Northern Rockhopper Penguin is sliding towards oblivion. Understanding what’s driving the decline of this bird will help us understand more about other threatened species in the Southern Ocean."
Possible factors for the decline of the Northern Rockhopper Penguin include climate change, shifts in marine ecosystems and overfishing.
"We are meant to be world leaders in biodiversity conservation and we can't even decide who is responsible for the overseas territories" —Sarah Sanders, RSPB’s Overseas Territories Officer
There is concern that the British Government will not put any great effort or resources into wildlife conservation for the United Kingdom’s overseas territories. Meetings held so far between ministers from the Foreign and Commonwealth Office, the Department for Environment, Food and Rural Affairs, and the Department for International Development have failed to reach agreement.
"They are completely disinterested," said Sarah Sanders, the RSPB’s Overseas Territories Officer, said. "It's ridiculous and embarrassing. We are meant to be world leaders in biodiversity conservation and we can't even decide who is responsible for the overseas territories."
The Northern Rockhopper Penguin population on Gough is estimated at 32,000 to 65,000 pairs, with another 40,000 to 50,000 pairs on Tristan. These two strongholds account for more than 80% of the world population, the rest are found on two French-administered islands, St Paul and Amsterdam in the Indian Ocean, and are declining just as rapidly.
British overseas territories boast several species of bird found nowhere else in the world including four species classified as Critically Endangered, the highest threat category.
Tackling the interlinked threats of habitat degradation, invasive species and climate change in UK Overseas Territories is one of 10 Key Actions to prevent future avian extinctions that BirdLife has highlighted in a new publication, Critically Endangered Birds: a global audit
Bird Conservation International is the official journal of BirdLife International. It provides stimulating, up-to-date coverage of bird conservation topics important in today's world. For more information: BirdLife: Bird Conservation International.
[1] Population trends and conservation status of the Northern Rockhopper Penguin Eudyptes moseleyi at Tristan da Cunha and Gough Island. R. CUTHBERT, J. COOPER, M. BURLE, C.J. GLASS, J.P. GLASS, S. GLASS, T. GLASS, G.M. HILTON, E.S. SOMMER, R.M. WANLESS and P.G. RYAN. Bird Conservation International 2009, 19: 1-12
Credits: RSPB
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2008 IUCN Red List Category (as evaluated by BirdLife International - the official Red List Authority for birds for IUCN): Endangered
Justification This newly split species has been classified as Endangered owing to very rapid population decreases over the last three generations (30 years) throughout its range. Precise reasons for the decline are poorly known, but changes in sea temperature, competition and incidental capture in fisheries and introduced predators are all likely to be implicated.
Family/Sub-family Spheniscidae
Species name author Mathews & Iredale, 1921
Taxonomic source(s) Banks et al. (2006)
Taxonomic note Eudyptes chrysocome (Sibley and Monroe 1990, 1993) has been split into E. chrysocome and E. moseleyi following Jouventin et al. (2006) on the basis of clear morphological, vocal and genetic terms, and this treatment has been accepted here following a review by the BirdLife Taxonomic Working Group. However, although E. filholi has been proposed as a split from E. chrysocome by Banks et al. (2006), both the sample sizes and the degree of morphological difference are small and this view is not accepted here.
Population estimate
Population trend
Range estimate (breeding/resident)
Country endemic?
100,000-499,999
decreasing
5,000,000 km2
No
Range & population Eudyptes moseleyi has recently been split from Eudyptes chrysocome. It breeds on Gough Island and islands in Tristan da Cunha (St Helena to UK), and Amsterdam and St Paul Islands (French Southern Territories). The large population at Gough Island appears to have been stable between 1982 and 20008, although it suffered large declines prior to the 1980s. The majority of the population is in the Atlantic Ocean (c. 80%)12. Early records indicate that millions of penguins used to occur on both Tristan da Cunha and Gough Island12. The most recent population estimates indicate declines in excess of 96% for Gough and 98% for the main island of Tristan that have occurred over at least 45 and 130 years, respectively12. Numbers breeding at Inaccessible Island (Tristan de Cunha) also may have declined, albeit modestly, whereas numbers on Tristan appear stable over the last few decades12. Current population estimates are 32,000-65,000 breeding pairs at Gough, 18-27,000 at Inaccessible and 3,200-4,500 at Tristan12. Trends for Nightingale and Middle Islands (both Tristan de Cunha) are poorly known12. They were estimated to support 125,000 pairs in the 1970s, but recent observations suggest that the main colony on Nightingale has decreased in size12. Overall, declines at Gough, Tristan and Inaccessible indicate an annual decline rate of 2.7% and a three-generation decline of 56%12. In the Indian Ocean, the Amsterdam Island population decreased by 57% between 1971 and 1993 to 25,000 pairs, whereas on St Paul Island they increased to 9,000 pairs over the same period, following cessation of exploitation as crayfish bait11. Population trends during the last 10 years in the Indian Ocean are unknown.
Ecology: It breeds in colonies, from sea-level to cliff-tops, and sometimes inland. It feeds on krill and other crustaceans, squid, octopus and fish7.
Threats Past human exploitation and the impact of introduced predators are likely to be responsible for past declines, but these factors cannot explain the sharp decreases since the 1950s 12. Food supplies may be affected by squid fisheries, climate change and shifts in marine food webs1,3,9. Increasing disturbance and pollution results from ecotourism and fishing2. Driftnet fishing and rock-lobster fisheries (which previously used birds for bait) has caused significant mortality5,6. On Nightingale, egging continues, perhaps causing decreases4,6. On some islands, introduced predators may affect breeding success5, and predation and competition for space with Subantarctic Fur Seals Arctocephalus tropicalis may cause declines locally.
Conservation measures underway Regular monitoring is, or will be, undertaken on Tristan da Cunha, Gough, Amsterdam and St Paul Islands8,10. Several ecological and demographic studies have been undertaken2,3. Many islands with breeding colonies are reserves.
Conservation measures proposed Continue or start to monitor all populations to asses trends. Conduct studies to assist in interpreting population changes and assessing interactions with commercial fisheries5. Investigate the impact of the introduced house mouse Mus musculus on chick survival on Gough. Eradicate introduced predators where possible5. Investigate impact of egg harvest on Nightingale10.
References 1. Cunningham and Moors (1994). 2. Ellis et al. (1998). 3. Guinard et al. (1998). 4. Richardson (1984). 5. Ryan and Cooper (1991). 6. P. G. Ryan in litt. (1999). 7. Williams, T. D. (1995). 8. Cuthbert and Sommer (in press). 9. Hilton et al. (in prep.). 10. Cuthbert and Sommer (2004). 11. Jouventin et al. (2006). 12. R. Cuthbert in litt. (2007).
Text account compilers Phil Benstead (BirdLife International), Jonathan Ekstrom (BirdLife International), Simon Mahood (BirdLife International), Rachel McClellan (BirdLife International), Sue Shutes (BirdLife International), Alison Stattersfield (BirdLife International)
Contributors Richard Cuthbert (Royal Society for the Protection of Birds), Geoff Hilton (Royal Society for the Protection of Birds)
IUCN Red List evaluators Stuart Butchart (BirdLife International), Simon Mahood (BirdLife International)
Recommended citation BirdLife International (2008) Species factsheet: Eudyptes moseleyi. Downloaded from http://www.birdlife.org on 18/1/2009
This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, and BirdLife International (2004) Threatened birds of the world 2004 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.
To provide new information to update this factsheet or to correct any errors, please email BirdLife
To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums
News and information courtesy of Birdlife International @
http://www.birdlife.org/news/news/2009/01/rockhopper_decline.html
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=32304&m=0
Saturday, January 17, 2009
Image of the Day
Penguins follow a lead bird, who often stops to see if everyone behind him/her is still following. I'm unsure as to this behavior on land, but penguins line up to plunge into the water in order to confuse a predator who may be lying in wait. By diving en masse into the water, there is enough confusion that the penguins can escape from a befuddled seal.
Following a lead bird is not symptomatic of penguins, alone. Watch geese fly in formation--they do so behind a lead bird. How that leader is designated is for researchers to determine. I just like to see penguins in a line headed for the beach. :)
Friday, January 16, 2009
Image of the Day
Few cultures have had the opportunity to include the penguin within its sphere of awareness and especially a culture that respects the animal's place in the world order of creatures.
Here is a pot found within a museum in South America and it is unknown whether it is modeled after the Humboldt or the Galapagos Penguin, but it's nice to see that someone other than our current culture appreciates the value of these birds.
Thursday, January 15, 2009
Image of the Day
A gang of king penguin bully-boys muscle their way past a little magellanic penguin. A gentoo penguin looks on from from the surf.
Although not an aggressive move, the kings are obviously determined to get out to sea and although seemingly rude, they only have one thing on their minds... food.
Wednesday, January 14, 2009
The 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 courtesy of ARKive @
http://www.arkive.org/yellow-eyed-penguin/megadyptes-antipodes/info.html
Images via Flickr
Tuesday, January 13, 2009
Monday, January 12, 2009
Like My Feathers?
Zhao Chuang and Xing Lida
Like My Feathers?
A reconstruction of Beipiaosaurus shows how the dinosaur may have displayed its feathers. The fossil, found in China, suggests the earliest feathers were for display purposes only.
Earliest Feathers for Show, Not Flight
Jennifer Viegas, Discovery News
Jan. 12, 2009 -- The world's first feathers probably had nothing to do with flight or staying warm but were instead for showy display purposes, according to a new study that documents the most primitive known version of feathers, which were found on a Chinese dinosaur.
The dinosaur, Beipiaosaurus, sported the likely colorful feathers on its limbs, trunk, tail, head and neck, with the neck feathers resembling a lion's mane.
Paleontologists now believe feathers evolved very early in archosaurs, the group that included dinosaurs, pterosaurs and relatives of crocodiles, in addition to today's modern birds, crocodiles and alligators.
"Our analysis suggests that feathers might have a much longer history than previously thought," lead author Xing Xu told Discovery News.
Story and picture courtesy of Discovery News @
http://dsc.discovery.com/news/2009/01/12/dinosaur-feathers.html
Sunday, January 11, 2009
Saturday, January 10, 2009
Images of the Day--Pygoscelis
P. antarctica
P. papua
P. adeliae
Mitochondrial and nuclear DNA evidence suggests the genus split from other penguins around 38 million years ago, about 2 million years after the ancestors of the genus Aptenodytes. In turn, the Adelie Penguins split off from the other members of the genus around 19 million years ago.*
There are also three extinct species:
1) Pygoscelis grandis (Bahía Inglesa Formation, Late Miocene/Early Pliocene of Bahía Inglesa, Chile)
2) Pygoscelis calderensis (Bahía Inglesa Formation, Late Miocene of Bahía Inglesa, Chile)
3) Tyree's Penguin, Pygoscelis tyreei (Pliocene of New Zealand)
* Baker AJ, Pereira SL, Haddrath OP, Edge KA (2006). "Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling". Proc Biol Sci. 273 (1582): 11–17.