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sydneyst
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 Posted: Tue Nov 11th, 2014 01:45 am

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Temperature Swings, Hunting and Sea-Level Rise as Killers of Woolly Mammoths

http://discovermagazine.com/2013/oct/05-what-killed-off-the-woolly-mammoths

excerpts:

By Jennifer Abbasi|Monday, September 09, 2013



Thinkstock

Ever since the early 1700s, when scientists such as Irish physician and collector Hans Sloan began studying the fossilized teeth and tusks of Siberian woolly mammoths, researchers have debated what caused the demise of these Ice Age behemoths.

Furry cousins of modern elephants, mammoths stomped their way across northern Eurasia and North America beginning 300,000 years ago. But between roughly 10,000 and 20,000 years ago, all except a few isolated island populations disappeared. Scientists believe the last of them may have died on Russia’s Wrangel Island in the Arctic around 1700 B.C.

In the early 20th century, 11,000-year-old cave paintings of woolly mammoths were found in France, suggesting, along with other discoveries of that time, that the creatures once lived side by side with humans. “Then came the chilling question: Were humans responsible?” says Glen MacDonald, a professor of geography, ecology and evolutionary biology at UCLA.

According to one hypothesis, prehistoric humans hunted most of the mammoths out of existence soon after coming into contact with them. But some researchers have argued that the transition from the frigid climatic period known as the Last Glacial Maximum (LGM) — about 20,000 to 25,000 years ago — to the current warm Holocene Epoch brought habitat changes that killed off the mammoths with little or no help from humans.

Evidence of the impact of one or more extraterrestrial objects 13,000 years ago in northern North America has led some scientists to posit that those events dramatically changed the climate, eventually wiping out the species.

Today, it’s believed that a combination of factors eliminated the mammoths, but determining exactly how it happened has been hampered by the scope of the mystery: “It’s a huge jigsaw puzzle that goes over thousands of years and extends across continents,” MacDonald says.

Last edited on Tue Nov 11th, 2014 01:48 am by sydneyst

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 Posted: Tue Nov 11th, 2014 01:26 am

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Story of Woolly Mammoth Extinction on Wrangel Island



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We usually think of woolly mammoths as purely Ice Age creatures. But while most did indeed die out 10,000 years ago, one tiny population endured on isolated Wrangel Island until 1650 BCE. So why did they finally go extinct?

Wrangel Island is an uninhabited scrap of land off the northern coast of far eastern Siberia. It's 37 miles from the nearest island and 87 miles from the Russian mainland. It's 2,900 square miles, making it roughly the size of Delaware. And until about 4,000 years ago, it supported the world's last mammoth population. For 6,000 years, a steady population of 500 to 1,000 mammoths endured while their counterparts on the mainland disappeared.

It's truly remarkable just how recent 1650 BCE really is. By then, the Egyptian pharaohs were about halfway through their 3000-year reign, and the Great Pyramids of Giza were already 1000 years old. Sumer, the first great civilization of Mesopotamia, had been conquered some 500 years before. The Indus Valley Civilization was similarly five centuries past its peak, and Stonehenge was anywhere from 400 to 1500 years old.

And through all that, with all of humanity in total ignorance of their existence, the mammoths lived on off the coast of Siberia.

So then, what finally killed off the mammoths? That's been the subject of a four-year research project by British and Swedish researchers, and they now believe that the final extinction of the mammoths was not inevitable, that they could have survived indefinitely if a couple circumstances had worked out differently. Co-author Love Dalen explained to BBC News:
"We wanted to find out why these mammoths became extinct. Wrangel Island is not that big and it was initially thought that such a small population could have suffered problems of inbreeding and a lack of genetic diversity. But the problem is mammoths don't display that much genetic variation - especially towards the end of their line. The DNA investigations found there was a 30% loss in genetic diversity as the population levels dropped - but that was to be expected. But when we examined the samples from the island, there reached a point when this reached a plateau and there was no more loss. This stage continued until the creatures became extinct. This therefore rejects the inbreeding theory. The mammoths on the island were isolated for nearly 6,000 years but yet managed to maintain a stable population."
Instead, Dalen and the rest of the team believes some drastic change must have occurred on Wrangel Island to kill off the mammoths, and there are two likely culprits: humans and climate. Archaeological evidence suggests that humans reached Wrangel Island at roughly the same time the last mammoths vanished, but there's no evidence yet to indicate that they ever hunted the mammoths. The more likely answer is climate change, which as a side effect might well have made it easier for humans to reach the island to serve as witnesses to the mammoths' final days.
Whatever the exact cause of the mammoth extinction, the fact that they did not succumb to inbreeding is very good news for conservation. According to the Dalen, this means that a small population of even a large animal can maintain genetic diversity and survive indefinitely on a small piece of land. And hey, if anyone ever does figure out how to clone a mammoth, I've got a very good idea where we should put their nature preserve.

Molecular Ecology[/url] via BBC News. Image by Catmando, via Shutterstock.

io9.com/5896262

Last edited on Tue Nov 11th, 2014 01:44 am by sydneyst

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 Posted: Thu Apr 11th, 2013 12:46 am

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Two-thirds of forest elephants killed by ivory poachers in past decade
http://www.guardian.co.uk/environment/2013/mar/05/two-thirds-forest-elephants-killed

The threat of extinction is growing for African forest elephants, according to a study released at the Cites summit in Bangkok.



There are about 100,000 forest elephants remaining in the forests of central Africa, compared with about 400,000 of the slightly larger savannah elephants. Photograph: Courtesy of TEAM Network/Conservation International The forest elephants of Africa have lost almost two-thirds of their number in the past decade due to poaching for ivory, a landmark new study revealed on Tuesday.

The research was released at an international wildlife summit in Bangkok where the eight key ivory-trading nations, including the host nation Thailand and biggest market China, have been put on notice of sweeping trade sanctions if they fail to crack down on the trade.

"The analysis confirms what conservationists have feared: the rapid trend towards extinction – potentially within the next decade – of the forest elephant," said Samantha Strindberg of the Wildlife Conservation Society (WCS), one of 60 scientists on the research team.

There are about 100,000 forest elephants remaining in the forests of central Africa, compared with about 400,000 of the slightly larger savannah elephants. The total elephant population was over 1 million 30 years ago, but has been devastated by poaching driven by the rising demand for ivory ornaments in Asia.

Prof Lee White, head of the National Parks Service in Gabon, once home to the largest forest elephant population, said: "A rainforest without elephants is a barren place. They bring it to life, they create the trails and keep open the forest clearings other animals use; they disperse the seeds of many of the rainforest trees – elephants are forest gardeners at a vast scale."

Forest elephants have suffered particularly badly because they range across central Africa, which has been left lawless in large areas by war, and where poachers have ready access to guns. Furthermore, the tusks of forest elephants are longer, straighter and harder than savannah elephants, making them particularly sought after. "A lot of carvers prefer forest elephant tusks," said WCS's vice president, Elizabeth Bennett.

Although deforestation is taking place, loss of habitat is not the principal problem for the elephants, according to another of the scientific team, John Hart of the Lukuru Foundation. "Historically, elephants ranged right across the forests of this vast region of over 2m sq km, but they now cower in just a quarter of that area. Although the forest cover remains, it is empty of elephants, demonstrating that this is not a habitat degradation issue. This is almost entirely due to poaching."

The new study, published in the journal Plos One, took nine years to complete and the team spent over 90,000 person-days in the field, walking over 13,000 km and taking 11,000 samples. They found the population fell by 62% between 2002 and 2011 and was now less than 10% of its potential size.

Last month, Gabon announced the death of about 11,000 forest elephants in the Minkébé national park between 2004 and 2012. Gabon's president, Ali Bongo Ondimba, says: "Our elephants are under siege because of an illegal international market that has driven ivory prices in the region up significantly. I call upon the international community to join us in this fight. If we do not reverse the tide fast the African elephant will be exterminated."

The 178-nation summit of the Convention on the Trade in Endangered Species (Cites) began in Bangkok on Monday and has already seen the eight countries identified as key to the ivory trade threatened with trade sanctions if they do not tackle failures in protection against poaching in Africa and failures in seizing illegal ivory along trade routes to China.

The nations, including the states which most ivory passes through – Tanzania, Kenya, Uganda, Malaysia, Philippines and Vietnam – and where most ivory is bought – China and Thailand - must come up with concrete action plans or face a ban on millions of dollars of trade in animals and plants, including crocodile skins and orchids.

The Thai prime minister opened the Cites summit by pledging to outlaw Thailand's domestic ivory trade which is currently legal. But she was criticised for failing to set a deadline.

Proposals to the Cites summit supporting and opposing more "one-off" sales of ivory will not succeed, the Guardian has been told. A previous "one-off" sale in 2008 was criticised by some as driving up demand, but defended by others as providing funds for elephant protection.

Cutting the demand for ivory, as well as fighting poaching, is seen as crucial, with African elephant deaths running at 25,000 a year. Bennett said better education programmes in China would be a vital part of the action plans: "A lot of people don't actually know that you have to kill elephants to get ivory."

Last edited on Thu Apr 11th, 2013 12:50 am by sydneyst

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 Posted: Tue Feb 12th, 2013 04:52 am

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Scientists Discuss Draconian Solutions for Saving Polar Bears

Accelerated Pack Recession Stirs Worries


http://www.guardian.co.uk/environment/2013/feb/07/polar-bears-fed-by-humans-survive

Polar bears 'may need to be fed by humans to survive' Drastic measures are required to save the beleaguered animal from extinction, say scientists

Some polar bears may have to be placed in temporary holding compounds until it is cold enough for them to go back on to the sea ice, say scientists. Photograph: Paul Souders/Corbis The day may soon come when some of the 19 polar bear populations in Canada, Alaska, Greenland, Norway, and Russia will have to be fed by humans in order to keep them alive during an extended ice-free season or prevent them from roaming into northern communities.

 Some bears may have to be placed in temporary holding compounds until it is cold enough for them to go back onto the sea ice. In worst-case scenarios, polar bears from southern regions may have to be relocated to more northerly climes that have sufficient sea ice cover.

Far-fetched, draconian, and unlikely as some of these scenarios may sound, 12 scientists from Arctic countries are, for the first time, suggesting that the five nations with polar bear populations need to start considering these and other management strategies now that sea ice retreat is posing serious challenges to the bears' survival.

In worst-case scenarios, the scientists say that polar bears with little chance of being rehabilitated or relocated may have to euthanized. Zoos, which are currently having a difficult time acquiring polar bears because of stringent regulations that prevent them from doing so, will at some point likely be offered as many animals
as they can handle, according to the scientists.

This crisis management plan for polar bears as Arctic sea ice disappears is laid out this week in an article in Conservation Letters, the journal of the Society for Conservation Biology. Polar bear experts Andrew Derocher, Steve Amstrup, Ian Stirling, and nine others say that with Arctic sea ice disappearing far faster than originally estimated, it's time for Arctic nations to begin making detailed plans to save as many of the world's 20,000 to 25,000 polar bears as possible.

"We really never have been here before," says Amstrup, chief scientist for Polar Bears International and a lead author of a landmark U.S. government-appointed panel that predicted in 2008 that two-thirds of the polar bears in the world could disappear by mid-century.

The University of Alberta's Derocher added, "We have covered the science side of the issue very well, but the policy and management aspects are locked in the past. We still manage polar bears in Canada like nothing has changed. Other countries are moving on some aspects of future polar bear management, but it is glacial compared to the actual changes we're seeing in sea ice and the bears themselves."

Last edited on Tue Feb 12th, 2013 05:01 am by sydneyst

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 Posted: Sun Feb 5th, 2012 06:40 pm

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Video of Wild Gorillas Visiting Camp in Uganda

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 http://www.youtube.com/v/1eXS0o6r-Wk%26rel%3d0%26hl%3den_US%26feature%3dplayer_embedded%26version%3d3

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 Posted: Sat Jul 16th, 2011 07:17 am

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Fourth wolf pack confirmed in Washington State

July 6th, 2011



 Biologists have confirmed a new wolf pack has taken up residence in Washington state — this one not far from Cle Elum, Kittitas County, near the Teanaway River.



It’s not exactly where the experts thought wolves would show up next.

But state biologists confirmed Tuesday that a new pack of gray wolves has taken up residence in Washington state — this time not far from Cle Elum, about 90 miles east of Seattle.

The Washington Department of Fish and Wildlife recently trapped one of the animals near the Teanaway River and took tissue and hair samples. DNA tests confirmed the animal is a female gray wolf and had been lactating, indicating she recently gave birth to pups.

While individual wolves may have been spotted in that area for years, it’s the first documented evidence that an entire pack has returned to Kittitas County since wolves were exterminated in the first half of the 20th century…

Read the entire article on seattletimes.nwsource.com: New wolf pack confirmed — a short drive from Seattle
Filed under: News Comment (0) Article tags: Washington

Last edited on Sat Jul 16th, 2011 07:18 am by sydneyst

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 Posted: Tue Jun 21st, 2011 11:33 am

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Fungus Infection Threatens World Toad and Frog Populations

http://www.sciencedaily.com/releases/2011/06/110620094856.htm

Fighting Massive Declines in Frog Populations With Bacteria and Fungicides





The midwife toad: a species that is particularly sensitive to the chytrid fungus. (Credit: Benedikt Schmidt)
ScienceDaily (June 20, 2011) — A microscopic chytrid fungus is causing massive declines in frog populations all over the world and even the extinction of certain species. Together with colleagues from Europe and the USA, researchers from the University of Zurich present methods as to how the chytrid fungus can be combated in the journal Frontiers in Zoology: namely with bacteria and fungicides. However, the possibility of vaccinating the frogs is also being considered.

New pathogens are not just a growing problem for humans and livestock, but also wild animals. Along with the destruction of their habitats and the overexploitation of their populations, a disease caused by a chytrid fungus called chytridiomycosis is one of the three biggest killers of amphibians in the world.

Devastating declines in amphibian populations were observed in Australia and Central America in the 1980s and 1990s. However, it wasn't until 1998 that the pathogen, the chytrid fungus Batrachochytrium dendrobatidis, was finally identified and described; the fungus has been spreading ever since. "Whenever it has turned up somewhere new, huge numbers of frogs have died from the disease," explains Benedikt Schmidt, a conservation biologist from the University of Zurich. What supposedly started out as a tropical disease has ballooned into a global problem. Today, the fungus can be found on every continent where there are frogs.

In Europe, the chytrid fungus and substantial declines in frog populations were first recorded in the mountains of Spain. "Wherever you looked for the fungus in Europe you found it," says Schmidt. In Switzerland, the fungus was detected in about half of all the ponds sampled. Almost all the indigenous amphibian species were, albeit to varying degrees, infected with the chytrid fungus. And individual amphibians that had perished from chytridiomycosis were also discovered in Switzerland, although not to quite such an extent as the mass deaths in other countries.

While the causes of "normal" hazards for frogs are well known and it is clear how we can help the amphibians, in the case of the chytrid fungus there are no known counter-measures. Researchers from the University of Zurich therefore teamed up with colleagues from Spain, Australia and the USA to examine possible approaches to fight the fungus. "Treating individuals in a zoo, for example, is a piece of cake," says Schmidt; "fighting the fungus out in nature, however, is a different kettle of fish altogether."

Last edited on Tue Jun 21st, 2011 11:36 am by sydneyst

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 Posted: Thu Mar 31st, 2011 04:56 am

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Respiratory disease in humans linked to deaths of wild mountain gorillas
March 30, 2011 |  

http://latimesblogs.latimes.com/greenspace/2011/03/respiratory-disease-humans-linked-to-deaths-wild-mountain-gorillas.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+GreenspaceEnvironmentBlog+%28Greenspace%29&utm_content=FaceBook



 
Humans have always posed the biggest threat to mountain gorillas, which for decades were poached for trophies and for sale on the world’s wild animal market. One gorilla died in Rwanda in 1992 after stepping on a landmine.

Now, a virus that causes respiratory disease in humans has been linked to the deaths of wild mountain gorillas, according to a study
conducted by researchers in Africa and two U.S. universities.

The finding, which for the first time confirms that life-threatening diseases can be transmitted by humans to these critically endangered animals, is of particular concern because the parks where Gorilla beringei beringei is protected in Rwanda, Uganda and the Democratic Republic of Congo are surrounded by the densest populations in Africa, the researchers said.

In addition, those nations count on gorilla tourism -- which brings thousands of people from around the world -- to help earn much-needed hard currency to fund local economies and the national parks that shelter the animals.

The researchers are from the nonprofit Mountain Gorilla Veterinary Project; UC Davis; the Center for Infection and Immunity at Columbia University; and the Rwanda Development Board. Their study was published online Monday by the journal Emerging Infectious Diseases, a publication of the U.S. Centers for Disease Control and Prevention.

Veterinarians had already noticed an increase in the frequency and severity of respiratory disease symptoms -- coughing, eye and nose discharge and lethargy -- among the total 786 wild mountain gorillas left in the world.

The study focused on a 2009 outbreak among 12 gorillas that was blamed for the deaths of an adult female and a newborn infant. Tissue samples from the stricken animals revealed the presence of nucleic acid from a virus known to scientists as human metapneumovirus.

In an interview, Kirsten Gilardi, assistant director of the UC Davis Wildlife Health Center, said, “We don’t know how or when the virus came into this gorilla population, but we do know it was most recently described as a human virus.”

“These animals are so closely related to us that it is not all a surprise they are susceptible to human
pathogens,” she added. “There are some measures we can take to better protect mountain gorillas from incursions of human infections. For example, in an open-air environment, if people stay seven yards away or farther from a gorilla, it would be far less dangerous for that animal.”

-- Louis Sahagun

Photo: Mountain gorilla mother and infant. Credit: UC Davis Wildlife Health Center


http://latimesblogs.latimes.com/greenspace/2011/03/respiratory-disease-humans-linked-to-deaths-wild-mountain-gorillas.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+GreenspaceEnvironmentBlog+%28Greenspace%29&utm_content=FaceBook

Last edited on Thu Mar 31st, 2011 05:05 am by sydneyst

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 Posted: Tue Feb 15th, 2011 06:03 am

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Birds Could Signal Mass Extinction
ScienceDaily (Oct. 12, 2010) — The first detailed measurements of current extinction rates for a specific region have shown that birds are the best group to use to track the losses. The study also reveals Britain may be losing species over ten times faster than records suggest, and the speed of loss is probably increasing: the losses from England alone may exceed one species every two weeks.

The study, by Oxford University researchers, shows that many types of obscure organism in Britain are going extinct at the same rate as the birds -- evidence supporting fears of a global mass extinction. A report of the research is published in an upcoming issue of the journal Biological Conservation as countries prepare to meet in Japan 18-29 October to discuss biodiversity conservation targets.

'Biodiversity loss is arguably much more serious and more permanent than climate change,' said Clive Hambler of Oxford University's Department of Zoology, lead author of the research. 'But it's impossible to know if policy targets to reduce the loss are being met without accurate measures of extinction rates. Until now, we had only crude estimates for a very few types of organism. Now we've got evidence that many groups of living things -- lichens, bugs, moths, fish, plants and so on -- are going extinct at a very similar rate to the birds.'

Using Britain's uniquely detailed natural history records, the researchers found that 1-5% of the region's species in many groups were lost since 1800, with higher losses in the Twentieth Century compared to the Nineteenth. Using further data from the USA and across the whole globe, the researchers show that the patterns of extinction in Britain are likely to be typical of those found on land and freshwater elsewhere.

Mr Hambler said: 'The birds are beautiful creatures, but they are also diverse, and many of them are specialised to particular habitats. This makes them sensitive to changes in their environment -- such as loss of mature trees, or the drying out of swampy ground, or coastal development. And what makes them really special for monitoring extinction is that they are also exceptionally easy to study, anywhere in the world -- so we can detect declines in their populations long before we notice losses of the more obscure things like slime moulds or mosses. It's no coincidence they can signal environmental change.'
'The underlying reason for the similarity of extinction rates in birds and the other living things is that habitat loss affects them in the same way. Our work supports the use of birds to indicate extinction rates in Britain, the USA and globally, and they should now be tried in places such as tropical forests where the bulk of other species will never be recorded.'

'The recorded extinctions in any region are just the tip of the iceberg, because there are not enough observers,' said Mr Hambler. For example, in March this year the British government's advisory body, Natural England, reported about 500 species lost from England since 1800. 'The losses reported by Natural England are under 0.5% per century, from England's 55,000 species,' notes Mr Hambler. 'Our research suggests that the actual losses could be over ten times this number, with about one species going extinct in England every fortnight.'

Natural England also reported species losses in England had apparently declined in recent decades, but the Oxford study suggests that this is not the case. Hambler and colleagues found there are about 1000 endangered species on the brink of extinction in Britain -- indeed many of these may already be extinct.

'People tend to be hesitant in declaring extinction, which leads to problems assessing the current rate,' said Mr Hambler. 'Many ancient and important habitats in Britain are threatened today because of human activity and population growth -- whether it's an increase in water use, growing use of wood fuel, or the growth of urban sprawl. Despite conservationists' efforts it's very likely extinction rates will continue to rise in Britain and globally for many years. These losses will impact on human welfare, and I'd say conservation needs a profile and resources even bigger than climate change.'

Alongside studies of birds, the researchers believe that recording rates of habitat loss will provide a good, simple measure of some elements of biodiversity loss.

Mr Hambler said: 'This work strengthens the claim that the world is suffering a mass extinction. We can now be much more confident that across the planet the less conspicuous and less well-known species are going extinct at a similar high rate to that already witnessed in birds, fish and amphibians.'

Last edited on Tue Feb 15th, 2011 06:04 am by sydneyst

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 Posted: Tue Feb 15th, 2011 05:43 am

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Mass Extinction Linked to Ancient Climate Change, New Details Reveal

http://www.sciencedaily.com/releases/2011/01/110127141703.htmScienceDaily (Jan. 27, 2011) —

About 450 million years ago, Earth suffered the second-largest mass extinction in its history -- the Late Ordovician mass extinction, during which more than 75 percent of marine species died. Exactly what caused this tremendous loss in biodiversity remains a mystery, but now a team led by researchers at the California Institute of Technology (Caltech) has discovered new details supporting the idea that the mass extinction was linked to a cooling climate.

"While it's been known for a long time that the mass extinction is intimately tied to climate change, the precise mechanism is unclear," says Seth Finnegan, a postdoctoral researcher at Caltech and the first author of the paper published online in Science on January 27. The mass extinction coincided with a glacial period, during which global temperatures cooled and the planet saw a marked increase in glaciers.

At this time, North America was on the equator, while most of the other continents formed a supercontinent known as Gondwana that stretched from the equator to the South Pole. By using a new method to measure ancient temperatures, the researchers have uncovered clues about the timing and magnitude of the glaciation and how it affected ocean temperatures near the equator. "Our observations imply a climate system distinct from anything we know about over the last 100 million years," says Woodward Fischer, assistant professor of geobiology at Caltech and a coauthor.

The fact that the extinction struck during a glacial period, when huge ice sheets covered much of what's now Africa and South America, makes it especially difficult to evaluate the role of climate. "One of the biggest sources of uncertainty in studying the paleoclimate record is that it's very hard to differentiate between changes in temperature and changes in the size of continental ice sheets," Finnegan says. Both factors could have played a role in causing the mass extinction: with more water frozen in ice sheets, the world's sea levels would have been lower, reducing the availability of shallow water as a marine habitat. But differentiating between the two effects is a challenge because until now, the best method for measuring ancient temperatures has also been affected by the size of ice sheets.

"By providing independent information on ocean temperature, this new method allows us to know the isotopic composition of 450-million-year-old seawater," Finnegan says. "Using that information, we can estimate the size of continental ice sheets through this glaciation." And with a clearer idea of how much ice there was, the researchers can learn more about what Ordovician climate was like -- and how it might have stressed marine ecosystems and led to the extinction.

"We have found that elevated rates of climate change coincided with the mass extinction," says Aradhna Tripati, a coauthor from UCLA and visiting researcher in geochemistry at Caltech.

The team discovered that even though tropical ocean temperatures were higher than they are now, moderately sized glaciers still existed near the poles before and after the mass extinction. But during the extinction intervals, glaciation peaked. Tropical surface waters cooled by five degrees, and the ice sheets on Gondwana grew to be as large as 150 million cubic kilometers -- bigger than the glaciers that covered Antarctica and most of the Northern Hemisphere during the modern era's last ice age 20,000 years ago.

"Our study strengthens the case for a direct link between climate change and extinction," Finnegan says. "Although polar glaciers existed for several million years, they only caused cooling of the tropical oceans during the short interval that coincides with the main pulse of mass extinction."


Last edited on Tue Feb 15th, 2011 05:48 am by sydneyst

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 Posted: Sun Dec 26th, 2010 06:26 am

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Conservation Fund Photographs Rare Saharan Cats

http://ecnmag.com/News/Feeds/2010/12/blogs-the-cutting-edge-more-photos-of-rare-saharan-cheetah-and-other-wild/


Photo of a sand cat by Thomas Rabeil of the Sahara Conservation Fund

In March of 2009 we posted about photos of the rare Saharan cheetahs caught on wildlife cameras. Recently more photos have been released by the Sahara Conservation Fund showing a ghostly cheetah and other wild cats and other wildlife, including this wonderful photo of a sand cat.

Elusive Saharan Cheetah Captured in Photos

The animal is so rare and elusive scientists aren’t sure how many even exist, though they estimate from the few observations they’ve made of the animal and tracks that fewer than 10 individuals call the vast desert of Termit and Tin Toumma in Niger home. Fewer than 200 cheetahs probably exist in the entire Sahara.

Their home can reach sizzling temperatures up to 113 degrees Fahrenheit (45 degrees Celsius), and is so parched no standing water exists. “They probably satisfy their water requirements through the moisture in their prey, and on having extremely effective physiological and behavioral adaptations,”

The Saharan cheetah is listed as critically endangered on the 2009 IUCN Red List of Threatened Species.


The elusive Saharan cheetah in Niger, Africa. Sahara Conservation Fund

The photos are part of the Sahara Carnivores Project

The Saharan race of cheetah (Acynonix jubatus hecki) is very rare, and one of the most specialized and threatened in Africa. As part of a major strategy to conserve Sahelo-Saharan wildlife, in collaboration with the Sahara Conservation Fund we are establishing a project to study and protect Saharan carnivores in the Termit/Tin Toumma region of north Niger. We aim to improve our understanding of sympatric Saharan carnivores, and evaluate the impact of human activities on carnivore populations, and that of carnivore predation on livestock. One of the projects aims is to produce an action plan prepared jointly with local land-users to minimize human-carnivore conflict in the Termit/Tin Toumma.
More ghostly cheetah photos: blurry and walking away

‘Ghostly’ Saharan cheetah filmed in Niger, Africa

it not yet known if Saharan cheetahs are more closely related to other cheetahs in Africa, or those living in Iran, which make up the last remaining wild population of Asiatic cheetahs.
Saharan cheetahs appear to have different colour and spot patterns compared to common cheetahs that roam elsewhere in Africa.
However, “very little is known about the behavioural differences between the two cheetahs, as they have never been studied in the wild,” says Dr Rabeil.
“From observations of tracks and anecdotal reports they seem to be highly adaptable and able to eke out an existence in the Termit and Tin Toumma desert.”

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 Posted: Sat May 15th, 2010 02:40 pm

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Lost lizards validate grim extinction predictions

http://www.newscientist.com/article/dn18899-lost-lizards-validate-grim-extinction-predictions.html

Predictions that climate change alone could lead to the extinction of more than one-fifth of plant and animal species before the end of the century have often come under fire, and not just from climate-change deniers. Some biologists are sceptical because the predictions are largely based on theoretical models. Now, the most detailed study yet of one group of species – lizards – suggests extinction levels could indeed be as bad as predicted. Crucially, the new forecast is based on actual data of what is driving lizards to extinction today on four continents.

The international team of researchers led by Barry Sinervo of the University of California, Santa Cruz, found that even though their habitats remained intact, the population of one group of lizards in Mexico has shrunk by 12 per cent since 1975 due to climate change. They found that the reptiles are disappearing because they need to spend more time in the shade to avoid overheating, leaving them less time to find food.

Silent spring
While lizards need to bask in the morning sun to warm up, they have to retreat into the shade later in the day to avoid heat stress. The hotter it gets, the less time they have to forage for food. Surprisingly, though, warmer springs rather than warmer summers are the killer, because this is the time when lizards reproduce and so need lots of extra food.

The team used its data from Mexico to predict where else lizards might be disappearing. They then compared their predictions with field studies of more than 1000 lizard populations on four different continents. They found that their predictions were accurate. Based on this, they predict that 20 per cent of lizard species will be extinct by 2080.

"This is surprising and very disturbing. None of us expected it," says Raymond Huey of the University of Washington in Seattle, who wrote an accompanying commentary on the study. "I would have predicted that lizards were less vulnerable to warming."
Models questioned Sinervo's forecast is significant because it is based on real-world studies of populations declining as the climate warms.

Until now, most estimates of how many species are threatened by climate change have been based on theoretical studies that look at the climatic and environmental conditions that species need to survive, and overlay this with estimates of how much suitable habitat will remain as the world warms.

"This study is really important because it shows that widespread extinctions associated with climate change are not simply a theoretical construct," says Chris Thomas at the University of York in the UK.

In a widely cited paper in 2004, Thomas and colleagues estimated that 15 to 37 per cent of terrestrial plant and animal species will be "committed to extinction" by 2050 (Nature, vol 427, p 145). Subsequent studies have reached similar conclusions. There is a lot of uncertainty about such predictions, he says, but it goes both ways: fewer species may die out than predicted, but then again, even more may go extinct.

Last edited on Sat May 15th, 2010 02:45 pm by sydneyst

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 Posted: Fri Apr 30th, 2010 04:06 pm

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Feds Enlarge Protected Zone for Troubled Dragonfly


By John Flesher, The Associated Press


Federal officials on Friday doubled the size of a protected zone in the Midwest for the Hine’s emerald dragonfly, the only dragonfly on the U.S. endangered species list.

The U.S. Fish and Wildlife Service said 26,532 acres in Illinois, Michigan, Missouri and Wisconsin are now designated as critical habitat for the insect, which is declining as the wetlands and sedge meadows on which it depends are drained for farming and other development.
"Thanks to the designation, Hine’s emerald dragonflies now have a chance to recover from the brink of extinction," said John Buse, senior attorney with the Center for Biological Diversity.

Although the dragonfly was declared endangered in 1995, no critical habitat was identified until 2007, after environmentalists filed a lawsuit accusing the government of dragging its feet.

The designation is important because it prohibits any federal agency from funding or issuing permits for activities in the area without checking with Fish and Wildlife Service biologists to make sure the dragonfly wouldn’t be harmed.

Originally, just 13,221 acres received the critical habitat label. Friday’s revised designation makes the protected area twice as large. It includes wet meadows and other places where the dragonfly breeds and forages.

The newly added acreage is within the Hiawatha National Forest in Michigan’s Upper Peninsula and the Mark Twain National Forest in Missouri.

Once abundant in the Midwest and found as far south as Alabama, the Hine’s emerald dragonfly now lives only in the four states where habitat has been set aside.

The insect has bright emerald-green eyes and a metallic green thorax, with yellow stripes on its sides. Its body is about 2.5 inches long, its wingspan about 3.3 inches.

In addition to wetlands destruction, scientists say other factors in its drop-off include logging, pipeline and road construction and off-road vehicles.

Courier-Life.

Last edited on Sat May 1st, 2010 08:36 pm by sydneyst

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 Posted: Tue Mar 30th, 2010 07:37 pm

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Arctic Species in Decline

http://arctic-council.org/article/2010/3/high_arctic_species_on_thin_ice


17 March 2010 High Arctic Species on Thin Ice By Jesper Hansen A new assessment of the Arctic’s biodiversity reports a 26 per cent decline in species populations in the high Arctic.

Populations of lemmings, caribou and red knot are some of the species that have experienced declines over the past 34 years, according to the first report from The Arctic Species Trend Index (ASTI), which provides crucial information on how the Arctic's ecosystems and wildlife are responding to environmental change.

While some of these declines may be part of a natural cycle, there is concern that pressures such as climate change may be exacerbating natural cyclic declines.
In contrast, population levels of species living in the sub-Arctic and low Arctic are relatively stable and in some cases, increasing.  Populations of marine mammals, including bowhead whales found in the low Arctic, may have benefited from the recent tightening of hunting laws.  Some fish species have also experienced population increases in response to rising sea temperatures.

"Rapid changes to the Arctic's ecosystems will have consequences for the Arctic that will be felt globally. The Arctic is host to abundant and diverse wildlife populations, many of which migrate annually from all regions of the globe.  This region acts as a critical component in the Earth's physical, chemical, and biological regulatory system," says lead-author Louise McRae from the Zoological Society of London (ZSL).

The Arctic Species Trend Index was commissioned by the Arctic Council's CAFF Circumpolar Biodiversity Monitoring Program.  The development of the index was a collaboration between the CBMP, the Zoological Society of London, UNEP World Conservation Monitoring Centre and the Worldwide Fund for Nature.  Further information is available from: http://www.asti.is/

The findings of the first ASTI report will be presented at the ‘State of the Arctic' Conference in Miami, USA.   The full report will be available to download from http://www.asti.is/ on Wednesday 17th March, 2010.

Last edited on Tue Mar 30th, 2010 07:39 pm by sydneyst

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 Posted: Sun Mar 21st, 2010 07:31 pm

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Wold Nations & Tribes Turn Down Measure to Protect Tuna and Endangered Species:
Are Elephants Next? 


http://www.nytimes.com/2010/03/19/science/earth/19species.html

U.N. Rejects Export Ban on Atlantic Bluefin Tuna
Delegates at a United Nations conference on endangered species in Doha, Qatar, soundly defeated American-supported proposals on Thursday to ban international trade in bluefin tuna and to protect polar bears.




“It wasn’t a very good day for conservation,” said Juan Carlos Vásquez, a spokesman for the United Nations organization. “It shows the governments are not ready to adopt trade bans as a way to protect species.”  Delegates voted down the proposal to protect bluefin by 68 to 20, with 30 abstentions. The polar bear measure failed by 62 to 48, with 11 abstention .  American officials expressed disappointment in the vote but said they would keep trying in various international forums to protect the tuna and the bears.

“The bluefin tuna is an iconic fish species,” said  Tom Strickland, assistant secretary of the interior for fish and wildlife and parks. “The science is compelling, the statistics are dramatic. That species is in spectacular decline.”

He said that the United States had recently declared the polar bear population to be threatened by loss of its sea ice habitat to melting. The  Interior Department, he said, had designated 200,000 acres of Arctic ice as critical habitat in need of protection.

“We believe the bear is under great pressure,” he said from Washington. “It should not be traded internationally.”

Canada, Greenland and several indigenous communities, which led the effort to defeat the proposal to protect the polar bear, contended that the bear population was healthy and that it could sustain limited hunting and trade in pelts and body parts.

Attention at the Doha conference will now turn to proposals to protect sharks and elephants. The United States, the Micronesian state of Palau and the European Union are among nations proposing that several species of sharks be listed under Appendix 2 of the convention, which would require that governments monitor trade in the species but would not entail an outright ban. But with Japan leading the opposition to any United Nations involvement in the regulation of marine species, and China, the largest consumer of shark fins, strongly opposed, the prospects of a deal appear remote.

The elephant talks will center on a proposal by Tanzania and Zambia to resume trade in elephant ivory, but Kenya and some other African nations argue that trade will bring only more poaching.

Last edited on Sun Mar 21st, 2010 07:47 pm by sydneyst


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