Tag Archives: Extinction

EXTINCTION: Rhinos face bleak future

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These images, via the Daily Mail and photographer Michael Raimondo, illustrate the extremes that conservationists must take in order to save wildlife from extinction. According to the Daily Mail, these “images show exactly how conservationists used a military helicopter to carry the herd of 1,400-kilo rhinos to their new home, away from poachers.”

According to the IUCN Red List of Threatened Species, several species of rhinoceros continue to hurdle towards extinction as poaching and habitat degradation, loss, and fragmentation continue to expand. The group also warns that “a quarter of all mammal species assessed are at risk of extinction.” The story of extinction is a story of human expansion. In order to stop extinction, governments must seriously implement policies that address overconsumption, alleviate imprudent development, and consider conservation. Without prudent conservation policies that work, more remarkable species will continue to go extinct. More via the AFP:

All told, a quarter of all mammal species assessed are at risk of extinction, the International Union for the Conservation of Nature (IUCN), which compiles the list, said on Thursday.

About a third of the 61,900 species now catalogued by the IUCN are classified as “vulnerable,” “endangered,” “critically endangered,” or extinct, with some groups, such as amphibians and reptiles, in particularly rapid decline.

Rhinoceros have been hit especially hard in recent years. Their fearsome horns — prized for dagger handles in the Middle East and traditional medicine in east Asia — can fetch hundreds of thousands of dollars on the black market.

The new assessment shows that a subspecies of the western black rhino (Diceros bicornis longipes) native to western Africa is now extinct, joining a long list of creatures — from the Tasmanian tiger to the Arabian gazelle — that no longer stride the planet.

Central Africa’s northern white rhino (Ceratotherium simum cottoni) is listed as “possibly extinct in the wild”, while the Javan rhino (Rhinoceros sondaicus) is making a last stand after the remaining specimen of its Vietnamese counterpart was killed by poachers last year.

“Human beings are stewards of the earth and we are responsible for protecting the species that share our environment,” Simon Stuart, head of the IUCN Species Survival Commission, said in a statement.

“In the case of both the western black and the northern white rhinos the situation could have had very different results if suggested conservation measures had been implemented.”

There were a few slivers of good news showing that species can be prevented from slipping into oblivion.

The southern white rhino subspecies (Ceratotherium simum simum) is back from the brink, its numbers up from 100 at the end of the 19th century to some 20,000 today.

Certainly, zoological parks will continue to play an important role in preventing species from vanishing from the Earth forever. Via McClatchy:

The eastern black rhinoceros is a critically endangered species, but the Kansas City Zoo just keeps churning them out.

Or, rather, it is Luyisa who has been doing the work, having just produced her third healthy calf in 10 years.

“Everybody was very thrilled about it,” said General Curator Liz Harmon, referring to the reaction of the zoo world and conservation experts to this birth, which occurred Oct. 18. “When it was born — and it was a girl — everybody was ecstatic.”

First, any birth in a species that only has a few hundred left in the wild is a good thing. Second, there are more males than females in the captive population, so girls are celebrated. Third, the father in this case had never sired a calf before, so his genes are not overrepresented.

And fourth, Luyisa, the mom, was born in the wild, so her genes are a welcome infusion into the captive gene pool.

The latest addition in Kansas City has been named Layla. The zoo has not made a splash about her because she won’t be on public display until the African section of the animal park reopens April 1, but The Kansas City Star got a sneak peak on Friday.

The Kansas City Zoo went to Africa to acquire Luyisa in 1997 in a trip chronicled by The Star. At the same time, the Cleveland Metroparks Zoo brought back a female of its own. She produced her fourth calf in August this year.

As a bonus, all seven offspring of those two animals have been female.

“It was good trip,” Harmon said of that 1997 expedition. “It helped the population a lot.”

EXTINCT SPECIES: Study determines that Tasmanian tiger’s jaws were too weak to kill sheep

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Image of a shot thylacine and thylacine cubs via Wikipedia

Scientists, with the help of computer software, recently discovered that the now-extinct Tasmanian tiger, or thylacine, wasn’t the sheep-killer that ranchers made them out to be. Via the BBC:

This digital “crash test” revealed that thylacine’s jaws were simply too weak to have brought down an adult sheep.

“If a large carnivore – like a big cat for example – wants to take down a big prey item, it has to clamp down on its throat and suffocate it,” said Dr Wroe.

“A thylacine wouldn’t have been capable of this.”

The digital “crash test” revealed the weak points in thylacine’s jaws
Dr Wroe also explained that thylacine’s teeth were “built for slicing” rather than for crushing bone.

Comparing its skull performance with closely related, living species with known diets, the scientists were able to predict the likely body size of its prey.

“It probably fed on small animals, such as possums,” said Dr Wroe. “And its limited diet would have made it more vulnerable to extinction.”

.       .       .

“The terrible loss of the thylacine signifies unjustified, negligent destruction of our native flora and fauna. It is a cautionary reminder of what we have lost, and that without urgent intervention other species will suffer the same fate.”

IVORY-BILLED WOODPECKER: More evidence suggests that the ivory-billed woodpecker isn’t extinct

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The images, by Dr. Michael Collins, are purported to be of ivory-billed woodpeckers living in Louisiana. Dr. Michael Collins’s images are via Wildlife Extra.

An amateur birdwatcher claims that photographs and audio recordings, which he took, are of ivory-billed woodpeckers living around the Pearl River area of Louisiana. Apparently, his evidence has been dismissed by the professional ornithological community. Nonetheless, he defends the authenticity of his data and is publishing his work in the Journal of the Acoustical Society of America. Via LiveScience.com:

[Michael] Collins is an outsider to the ornithology community—he’s just a hobbyist bird-watcher—and few insiders take his work seriously. His evidence has been rejected by a string of ornithology journals – often, he says, without explanation.

And so he has turned to acoustics scientists to confirm his recordings. This month he will finally publish what he believes is solid evidence that ivory-billed woodpeckers live at Pearl River in the Journal of the Acoustical Society of America.

Collins, a researcher at the Naval Research Laboratory-Stennis Space Center in Mississippi, first started searching for the bird when a team of Cornell ornithologists captured putative footage of a specimen in Arkansas in 2005. That possible sighting, the first well-documented (though not definitive) human encounter since about 1940, made it onto the cover of Science Magazine. The birds were said to have lived at Pearl River in the past, so when Collins heard that they might still exist as a species, he decided to look for them there.

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The audio recordings, which he obtained in conjunction with the videos, also smack of the Lord God bird, which makes very distinct double knocks when pecking, and makes vocalizations somewhat like a blue jay’s and nothing like a pileated woodpecker’s. Collins used his mathematics expertise to construct sophisticated acoustical models of the bird’s vocalizations. The audio and video evidence combined, he says, give firm support to his claim that ivory-billed woodpeckers live at Pearl River.

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“Professional jealousy is a huge problem in the field of ornithology,” Collins said. “There are groups who have received a lot of funding to obtain conclusive data on these birds and haven’t managed to do so, and I’ve done it independently.” One such group, he said, is the Cornell Lab of Ornithology, the country’s leading center of ornithology research and the group who may have sighted the elusive woodpecker in 2005.

.       .       .

The Cornell group, which Collins accuses of having exerted its influence to keep his work out of ornithology journals, commented briefly on his new acoustics paper.  ”Although we believe the evidence presented is inconclusive, we applaud Collins’s continued efforts to locate and document possible ivory-billed woodpeckers and to publish his findings for all to evaluate,” Kenneth Rosenberg, director of conservation science in the group, said.

You can read the rest of this article at LiveScience.com. More on Collins’s claims can be found at Wildlife Extra.

EXTINCT SPECIES: Man claims to have purchased Tasmanian tiger pelt for $5

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The image of Bill Warren with his Tasmanian tiger pelt was taken by Charlie Neuman. The other images below depict the tiger in captivity and as a hunted animal.

A man claims to have purchased a Tasmanian tiger pelt from a garage sale in San Diego for just five dollars, but the pelt, if verified, is worth thousands more. From the San Diego Union Tribune:

[Bill] Warren might turn a $5 buy into $70,000 after finding what appears to be the pelt of an extinct Tasmanian tiger at a garage sale.

Warren found the unusual looking animal skin in Rainbow in June. The owner had bought the skin some 30 years ago at another garage sale in Boston.

“I didn’t know what it was, and neither did she,” Warren said. But he had a hunch it was something interesting.

.       .       .

“They’re a very rare item to come across,” said Andrew Snooks from Armitage Auctions in Australia.

Snooks said the auction house is negotiating with Warren to obtain the pelt. After the house confirms that the pelt is indeed a Tasmanian tiger, it will go up on the auction block.

Snooks said the last Tasmanian tiger pelt sold at the auction house went for $68,000, and a rug made from eight pelts sold for $260,000.

Of course, there is still the business of verifying the pelt. Warren sent photos of the animal skin to John Long, vice president of research and collections at the Natural History Museum of Los Angeles. Long responded by e-mail that it looked like a Tasmanian tiger, but only expensive testing could confirm it.

The Tasmanian tiger, or thylacine, Thylacinus cynocephalus, is a presumably extinct species of marsupial carnivore. It once ranged from Papua New Guinea to Australia and south into Tasmania, and “wild thylacines were present until the early 1900s; the last known captive specimen died in Hobart Zoo in 1936.”

The extinction of the thylacine is blamed on competition with the dingo, which probably arrived with humans thousands of years before. In more modern times, the targeted eradication of the thylacine on the island of Tasmania — the species’ last stronghold — helped doom the unique animal to extinction (although it may still exist in very remote regions of Tasmania).

The thylacine is an example of convergent evolution. It’s neither a tiger or a dog. Although it strongly resembles a dog, coyote, or wolf, it’s not related to these species, which belong to the family Canidae. The thylacine belongs to the family Thylacinidae, and they’re also marsupials, while dogs are placental mammals.

Images found here, here, here, here, here, and here.

EXTINCTION: Mass extinction “changes the rules of evolution”

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Image via la picarita on Flickr

Anthropogenic activities are resulting in rapid habitat degradation, loss, and fragmentation, which fuel more extinctions of species that can’t adapt to human-dominated environments. This period of Earth’s history, which is dominated by human activities, is often referred to as the anthropocene. According to recent research, mass extinction, which is currently fueled by an increase of human populations and activities, may forever change the outcome of evolution. More via Wired.com:

Rates of species diversification — the speed at which groups adapt and fill open ecological niches — seemed to predict what’s flourished in the aftermath of past planetary cataclysms. But according to the calculations of Macquarie University paleobiologist John Alroy, that’s just not the case.

“Mass extinction fundamentally changes the dynamics. It changes the composition of the biosphere forever. You can’t simply predict the winners and losers from what groups have done before,” he said.

.       .       .

In the past, many evolutionary biologists thought life would eventually recover its present composition, said Alroy. In 100 million years or so, the same general creatures would again roam the Earth. “But that isn’t in the data,” he said.

Instead Alroy’s analysis suggests that the future is inherently unpredictable, that what comes next can’t be extrapolated from what is measured now, no more than a mid-Cretaceous observer could have guessed that a few tiny rodents would someday occupy every ecological niche then ruled by reptiles.

“The current mass extinction is not going to simply put things out of whack for a while, and then things will go back to where we started, or would have gone anyway,” said Alroy. Mass extinction “changes the rules of evolution.”

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