Guest post by Dr. Craig Loehle
Last year, Willis Eschenbach had a WUWT post about extinction rates being exaggerated in the literature. I offered to help him get this published, and it is now out. We conclude that the extinction crisis for birds and mammals is very specific to island fauna which are uniquely sensitive to human impacts, including our pets and commensals like rats. It is not valid to extrapolate these extinctions to either the problem of deforestation on continents or to future impacts of climate change.
The process of getting this published was relatively painless which is surprising given how much we counter conventional wisdom in it. The paper is available free at Researchgate.
I would argue that blogs CAN be a real part of the scientific process. I would recommend that people follow up on good ideas they see and get them into print as this example illustrates.
Loehle, C. and W. Eschenbach. 2011. Historical Continental Bird and Mammal Extinction Rates. Diversity & Distributions DOI: 10.1111/j.1472-4642.2011.00856.x
Methods: We examined historical extinction rates for birds and mammals and contrasted island and continental extinctions. Australia was included as an island due to its isolation.
Results: Only six continental birds and three continental mammals were recorded in standard databases as going extinct since 1500 compared to 123 bird species and 58 mammal species on islands. Of the extinctions, 95% were on islands. On a per unit area basis, the extinction rate on islands was 177 times higher for mammals and 187 times higher for birds than on continents. The continental mammal extinction rate was between 0.89 and 7.4 times the background rate, whereas the island mammal extinction rate was between 82 and 702 times background. The continental bird extinction rate was between 0.69 and 5.9 times the background rate, whereas for islands it was between 98 and 844 times the background rate. Undocumented prehistoric extinctions, particularly on islands, amplify these trends. Island extinction rates are much higher than continental rates largely due to introductions of alien predators (including man) and diseases.
Main Conclusions: Our analysis suggests that conservation strategies for birds and mammals on continents should not be based on island extinction rates, and that on islands the key factor to enhance conservation is to alleviate pressures from uncontrolled hunting and predation.
Table 1: Extinctions since 1500 according to IUCN and CREO, with per species and per unit area rates.
Abstract:
Loehle, Craig, and Willis Eschenbach. 2011. Historical bird and terrestrial mammal extinction rates and causes.
Diversity and Distributions. doi: 10.1111/j.1472-4642.2011.00856.x
We examined historical extinction rates for birds and mammals and contrasted island and continental extinctions. Australia was included as an island because of its isolation. Only six continental birds and three continental mammals were recorded in standard databases as going extinct since 1500 compared to 123 bird species and 58 mammal species on islands. Of the extinctions, 95% were on islands. On a per unit area basis, the extinction rate on islands was 177 times higher for mammals and 187 times higher for birds than on continents. The continental mammal extinction rate was between 0.89 and 7.4 times the background rate, whereas the island mammal extinction rate was between 82 and 702 times background. The continental bird extinction rate was between 0.69 and 5.9 times the background rate, whereas for islands it was between 98 and 844 times the background rate. Undocumented prehistoric extinctions, particularly on islands, amplify these trends. Island extinction rates are much higher than continental rates largely because of introductions of alien predators (including man) and diseases. Our analysis suggests that conservation strategies for birds and mammals on continents should not be based on island extinction rates and that on islands the key factor to enhance conservation is to alleviate pressures from uncontrolled hunting and predation.
Copyright © 2011 by Blackwell Publishing Ltd. All rights reserved. Article posted on this website with permission.
Download the paper 
(Adobe PDF) Loehle & Eschenbach2011
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Congratulations!
Perhaps the weight of “commonsense” will prevail, eventually.
Well done.
Glad to see Team Watts in print. An article here, an article there, and rays of reality will start to shine. Congrads Willis.
The continual drip drip of calm corrections of wild alarmist claims is starting to have an impact. More of these extended well argued posts on this and other sites should be peer reviewed and published.
Bravo!
Now the question is whether it gets into the AR5 and, if it appears, how it’s treated.
On second thought, you rate more than a “Bravo” so I am sending along an island cheer:
Congratulations Craig and Willis!
Since you are incomparably more competent than the “delinquent teenagers” to prepare the IPCC-AR, they’ll recruit you for AR6??
Congratulations to you both. Well done.
Congratulations Willis and Dr. Loehle…well done!
Congratulations!
Will we next be seeing a paper on the economic benefits of CO2 and increased crop yields. Surely there is a relationship between food production, population and economic output.
Grats, It is nice to read something that isn’t written on slant.
Well Done !
The Great Auk, or gairfowl (Pinguinus impennis) became extinct in the mid-19th century.
The Passenger Pigeon or Wild Pigeon (Ectopistes migratorius) became extinct at the end of the 19th century.
The Arabian gazelle (Gazella arabica) was hunted to extinction in about 1830.
Hensel’s field mouse (Rhagamys orthodon) disappeared from Britain and Ireland in the last 50 years.
This week the last Vietnamese rhinoceros was killed by poachers, shot through the legs and horn sawed off.
I hope that we will be able to bring back some of these extinct creatures someday, such as the dodo and passenger pigeon. I’m sure we have DNA of each.
And Antarctica? — Ah, excluded with Greenland.
Minor grammatical note. In the first paragraph is the line
“We conclude that the extinction crisis for birds and mammals is very specific to island fauna which are uniquely sensitive to human impacts, including out pets and commensals like rats.”
I have many gay and lesbian friends, but I’ve yet to see any of our pets come out. Or did you mean “our pets”? 😉
Congratulations too on being published by the way.
JE [Fixed … and very funny too.]
I remember the original “Where are the corpses?” article. Good to see it’s in the literature now. Congratulations.
“Island extinction rates are much higher than continental rates largely due to introductions of alien predators (including man) and diseases.”
One idea could be to show negative Anthropogenic influences weighed against positive Anthropogenic influences on extinction rates. Modern Humans for the first time as far as we know in earths entire history are the only species ever to be actively involved in the prevention of other species from extinction, and contribute to the introduction of species to new environments, that in-turn insure the increase of survival rates and growth of their populations. I believe this to be a fact, and therefore I don’t think humans should be just lumped together along with diseases and other predators. I despise the idea, but if you feel that humans [are] or [not] similar to a disease, It would be fair to add some further elaboration on this either way.
Once again – no need to panic
“Just the facts” please
The great shame of the AGW who-ha is that it detracts attention from the real causes of what is happening.
There are some changes in the environment that are adverse, from a human perspective.
Some of those adverse changes can be reduced or even eliminated.
Spending huge amounts of money, attention and effort of fairy tale solutions on problems that are just stormy night nightmares of no real substance, just detract from the effort that should be made to created real improvement to our position.
Is a published paper really published if no editor resigns over it?
Well done!
Sparks.
We are predators pure & simple.
Unfortunately, we are cursed with what passes for intellect and a conscience.
We see things we perceive as being wrong, (eg extinction of species,) then have the hubris to think we can fix it.
Take for instance kites & magpies. They’re now protected & everyone’s wondering what’s happening to all the songbirds. No-one seems to have figured out they’re the prey of kites & magpies!
Animal Liberation Front released loads of mink & then wonder what happened to the otters, similar thing.
If we’re a disease, so are kites, magpies, polar bears, wolves, foxes and any number of other predators, it’s just that they don’t think about it because they’re to busy trying to survive, same as many primitive humans.
DaveE.
Haha, oh wow
Including Australia as an “island” sure is convenient when it also happens to have one of the highest extinction rates, don’t you think?
What happens to the estimates if Australia is counted as a continent?
The obvious solution is to “protect” songbirds and otters, too. Then restraining orders can be issued, and all will be returned to natural …
Oh, wait.
Not only is this a great analysis of the data, it’s also a very interesting read. Thank you.