Before you read this, I’ll remind WUWT readers of this essay:
Where Are The Corpses? Posted on January 4, 2010 by Willis Eschenbach
Which is an excellent primer for understanding the species extinction issue. Willis pointed out that there are a lot of holes in the data collection methods, and that has proven itself this week when this furry little guy (below) announced himself to a couple of volunteer naturalists at a nature reserve in Colombia two weeks ago and was identified as the thought to be extinct red-crested tree rat. It hasn’t been seen in 113 years. Oops.
IPCC report based on “fundamentally flawed” methods that exaggerate the threat of extinction – The pace at which humans are driving animal and plant species toward extinction through habitat destruction is at least twice as slow as previously thought, according to a study released Wednesday.
Earth’s biodiversity continues to dwindle due to deforestation, climate change, over-exploitation and chemical runoff into rivers and oceans, said the study, published in Nature.
“The evidence is in — humans really are causing extreme extinction rates,” said co-author Stephen Hubbell, a professor of ecology and evolutionary biology at the University of California at Los Angeles.
But key measures of species loss in the 2005 UN Millennium Ecosystem Assessment and the 2007 Intergovernmental Panel on Climate Change (IPCC) report are based on “fundamentally flawed” methods that exaggerate the threat of extinction, the researchers said.
The International Union for the Conservation of Nature (IUCN) “Red List” of endangered species — likewise a benchmark for policy makers — is now also subject to review, they said.
“Based on a mathematical proof and empirical data, we show that previous estimates should be divided roughly by 2.5,” Hubbell told journalists by phone.
“This is welcome news in that we have bought a little time for saving species. But it is unwelcome news because we have to redo a whole lot of research that was done incorrectly.”
Up to now, scientists have asserted that species are currently dying out at 100 to 1,000 times the so-called “background rate,” the average pace of extinctions over the history of life on Earth.
UN reports have predicted these rates will accelerate tenfold in the coming centuries.
The new study challenges these estimates. “The method has got to be revised. It is not right,” said Hubbell.
How did science get it wrong for so long?
Because it is difficult to directly measure extinction rates, scientists used an indirect approach called a “species-area relationship.”
This method starts with the number of species found in a given area and then estimates how that number grows as the area expands.
To figure out how many species will remain when the amount of land decreases due to habitat loss, researchers simply reversed the calculations.
But the study, co-authored by Fangliang He of Sun Yat-sen University in Guangzhou, shows that the area required to remove the entire population is always larger — usually much larger — than the area needed to make contact with a species for the first time.
“You can’t just turn it around to calculate how many species should be left when the area is reduced,” said Hubbell.
That, however, is precisely what scientists have done for nearly three decades, giving rise to a glaring discrepancy between what models predicted and what was observed on the ground or in the sea.
Dire forecasts in the early 1980s said that as many as half of species on Earth would disappear by 2000. “Obviously that didn’t happen,” Hubbell said.
But rather than question the methods, scientists developed a concept called “extinction debt” to explain the gap.
Species in decline, according to this logic, are doomed to disappear even if it takes decades or longer for the last individuals to die out.
But extinction debt, it turns out, almost certainly does not exist.
“It is kind of shocking” that no one spotted the error earlier, said Hubbell. “What this shows is that many scientists can be led away from the right answer by thinking about the problem in the wrong way.”
Human encroachment is the main driver of species extinction. Only 20 percent of forests are still in a wild state, and nearly 40 percent of the planet’s ice-free land is now given over to agriculture.
Some three-quarters of all species are thought to live in rain forests, which are disappearing at the rate of about half-a-percent per year.
Species–area relationships always overestimate extinction rates from habitat loss
Nature473,368–371(19 May 2011)
Extinction from habitat loss is the signature conservation problem of the twenty-first century1. Despite its importance, estimating extinction rates is still highly uncertain because no proven direct methods or reliable data exist for verifying extinctions. The most widely used indirect method is to estimate extinction rates by reversing the species–area accumulation curve, extrapolating backwards to smaller areas to calculate expected species loss. Estimates of extinction rates based on this method are almost always much higher than those actually observed2, 3, 4, 5. This discrepancy gave rise to the concept of an ‘extinction debt’, referring to species ‘committed to extinction’ owing to habitat loss and reduced population size but not yet extinct during a non-equilibrium period6, 7. Here we show that the extinction debt as currently defined is largely a sampling artefact due to an unrecognized difference between the underlying sampling problems when constructing a species–area relationship (SAR) and when extrapolating species extinction from habitat loss. The key mathematical result is that the area required to remove the last individual of a species (extinction) is larger, almost always much larger, than the sample area needed to encounter the first individual of a species, irrespective of species distribution and spatial scale. We illustrate these results with data from a global network of large, mapped forest plots and ranges of passerine bird species in the continental USA; and we show that overestimation can be greater than 160%. Although we conclude that extinctions caused by habitat loss require greater loss of habitat than previously thought, our results must not lead to complacency about extinction due to habitat loss, which is a real and growing threat.
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Kept this article from last 29 Sept:
“Back from the dead: One third of ‘extinct’ animals turn up again
The revelations come as the world’s leading conservationists prepare for a major United Nations summit on biodiversity in Nagoya, Japan, next month. ..
Dr Diana Fisher, of the University of Queensland, Australia, compiled a list of all mammals declared extinct since the 16th century or which were flagged up as missing in scientific papers.
‘We identified 187 mammal species that have been missing since 1500,’ she wrote in the journal Proceedings of the Royal Society B.
‘In the complete data-set, 67 species that were once missing have been rediscovered. More than a third of mammal species that have been classified as extinct or possibly extinct, or flagged as missing, have been rediscovered.’
Mammals that suffered from loss of habitat were the most likely to have been declared extinct and then rediscovered, she said…
The mistakes cannot be blamed on primitive technology or old fashioned scientific methods.
‘Mammals missing in the 20th century were nearly three times as likely to be rediscovered as those that disappeared in the 19th century,’ Dr Fisher added.”
http://www.dailymail.co.uk/news/article-1315964/One-extinct-animals-turn-again.html
The amount of money stolen by the bankrobbers was heavily exaggerated and fundamentally flawed.
The estimated stolen $ 10 mln turned out to be only $ 6 mln.
Blame the guy who didn’t count very carefully! Blame him! He’s an alarmist! Blame him!
Yours,
BankRobert
“But extinction debt, it turns out, almost certainly does not exist.”
Whoever wrote that either did not read, did not understand the paper, or chose to mislead.
He and Hubbell are clear that the definition of extinction debt as the difference between actual extinction and extinction predicted by the SAR is incorrect. However they also write “Note that these results say nothing about whether an extinction debt exists”.
Anybody who doubts that extinction debt is a valid concept, that species, destined for extinction can persist for one, or more generations, before finally becoming extinct, need only consider Lonesome George.
‘The pace…is at least twice as slow as previously thought’
Ouch!
What’s wrong with
‘The pace…is less than half as fast as previously thought’
Why can’t academics write straightforward English? Is Obfuscation & Prolixity 101 a compulsory class in Nerd School?
EVERYTHING about the IPCC appears toi be fundamentally flawed. But still governments hang on their every word. Crazy.
These ‘conservationists’ are always on to a winner. Say a visit to ‘darkest New Guinea’ reveals 4 new toads and 3 new rats then, with only one or two pairs of each ‘in existence’, that’s fantastic, 7 new species to add to the ‘critically endangered’ list !
Oh, and allow two years to pass, fail to find the site again, and 7 more species are ‘extinct’. Simples !
Well said, Poptech! You also might want to add the one about the “lost tiger population of Bhutan”, which was rediscovered last year living in the mountains where zooological experts had said it was impossible for them to live at such an altitude. Then modern technology discovers them on camera doing the exact opposite. Isn’t mother nature wonderful? I also recall news 30 year + ago of fishermen catching a fish off the west coast of Africa which was thought to have been extinct for millions of years (no idea if it was ever true). One wonders just how at risk threatened species really are. A bit like the “Amercian” Polar Bear population I expect. I am no expert by any means, but could there just be the remotest of possibilities that these creatures have learned to adapt to their environment to survive?………………..naaah, that’s just stupid thinking, what a klutz!
It is a case of-‘there were two in the garden yesterday and now they’re gone. Must be extinct.’
Counting methods leave a lot to be desired especially for those, like the tiger, which like a solitary existence. A recent BBC nature program reported the count of tigers in Bhutan and expected to find 100 or so but actually found an estimated 3000 of these beautiful creatures.
All the scare stories do not include any about new species being discovered every day as our search methods improve and the ability to reach the more inaccessible improves.
Willis was also vindicated with his floating islands post.
http://wattsupwiththat.com/2010/01/27/floating-islands/
http://linkinghub.elsevier.com/retrieve/pii/S0921818110001013
And probably much slower than that. This, among other areas, is where environmentalists should be concentrating.
You can always tell a closet totalitarian in green clothing, because they will find a story like this and point out the bad news, rather than concentrating on the fact that the things they have been fretting over aren’t as bad at all, and on current trends, likely to not be a problem in the end.
They will see something like this and say ‘it was wrong this time, and the time before that, and the time before that. But we have to do something ™ now! Before it is too late ™’
I’m a bit dismayed none of those people have shown up here. I fully expected a couple of comments like that. But then most closet totalitarians seem to be aware the game is increasingly up and don’t do drive by comments anymore. Perhaps ‘denier alerts’ has folded or something.
“What this shows is that many scientists can be led away from the right answer by thinking about the problem in the wrong way.”
Indeed. Scientists, particularly those in the environmental/climate fields perhaps need to re-learn how think about things in the correct, aka scientific way. But, is it even possible? I lay the blame directly on how they are being taught. They have been lead astray by post-normal thinking, wherein emotion and advocacy trump scientific method.
What’s really weird is that greenpeezers and WWFers only have to take a closer look at a specie for it to become extinct. Talk about evil eyes. 0_O
Whenever someone tells me that x number of species go extinct every year, I always reply “Name two.”
Isn’t this a dupe? I am sure we had this here a day or so ago….
The good folks over at The Resilient Earth examined this so-called bio-diversity scare a couple of months ago:
http://theresilientearth.com/?q=content/price-biodiversity
“But you can’t quantify species extinction if you can’t identify the species in the first place. Back in 2000, famed Harvard University ant biologist Edward O. Wilson estimated that it would cost $5 billion to identify every species on Earth, not just animals. Wilson admitted at the time that, even among the small minority of all species diagnosed and named, fewer than 1% have been subject to the kind of careful biological studies needed to undergird ecology and conservation biology.”
Observations from Indianapolis:
Animals I have seen in my area of the northern part of Indianapolis and southern part of Carmel, IN (not “Car mel” as in California but “carml” as in Indiana) over the past five years of living here.
(1) Deer living in and around housing areas.
(2) Hawks (red tailed and chicken)
(3) Owl (pair of barred owls, I am looking for their babies but have not seen them yet)
(4) Fox (mother and three pups seen and photographed in my neighbor’s back yard). I heard recently that over 50 foxes were removed from Camel, IN.
That does not include the fawna seen in my yard (my wife can give you all the names I an not that blessed).
God has created a tremendous adaptability in life that we humans discredit.
I guess the point is to keep your eyes and ears open to what is living around us.
My favorite has been the mantra that the rainforests have been razed by man and will never recover. This article (which I saw originally in the NY Times) talks about how abandoned farmland is returning to rainforest at a rate estimated to be 50 new acres of rainforest for every 1 destroyed. And there is no sign that these lands cannot return to their original biological productivity levels.
http://gliving.com/media-watch-abandoned-farm-land-reverting-to-jungle-raises-new-debates/
I was amused to find that the IPCC fantasy of the effects of CO2, albeit exaggerated from is final estimate of 1°C per doubling, is rooted in the same person’s work as the species’ populations studies, Arrhenius.
http://www.ecosystems.ws/species_area_relationship_arrhenius.htm
Re Shevva
Or if the wrong kind of conservation has increased losses of biodiversity. Some of the woodsmen here have commented about forest management or mismanagement may have led to an increase in fire tolerant species at the expense of less tolerant ones.
I missed the “h” in ‘his final estimate’, at 5:45. Forgot to mention they ‘re-introduced’ the lynx in western Colorado about 2002. I guess the one that was looking into my living room in 1995 through the glass door must have died.
Rumors of my death are greatly exaggerated.
GWPF quoted in the original post said: “Human encroachment is the main driver of species extinction. Only 20 percent of forests are still in a wild state, and nearly 40 percent of the planet’s ice-free land is now given over to agriculture.” (I think they are paraphrasing Hubbell.)
Someone asked about the 40% figure. Is Science Daily this is presented differently:
“Humans are already using 40 percent of all the “plant biomass” produced by photosynthesis on the planet, a disturbing statistic because most life on Earth depends on plants, Hubbell noted. “
Given how little we know about historical species (how many fossils have been found???), it is amazing that some want to believe they know so much about the current trends as to label them “extraordinary”. All we do know is that stuff happens and species go out of existence all the time. A fossilized bone of a tree frog is not much different than a swamp speckled frog, yet today they are different species with one endangered and the other not. Who says the 2 fossils from the past were not the same species or different?
It seems that some areas of science have taken up the incompetent rant of the journalist profession – do not report the results – make them up!
In terms of how species are likely to become extinct, loss of habitat always seemed liked a perfectly reasonable argument. That any species extinction can be attributable to AGW always seemed rather unlikely.
How is Earths biodiversity dwindling due to climate change? This isn’t rhetorical, I would actually like someone to answer?
DavidS