Amphibian decline – climate change not the single culprit

Like the recent smackdown of the “plankton are declining” nonsense, compare the new paper from OSU below to this reporting from 2008:

click for the full story

From Oregon State University:

Catastrophic amphibian declines have multiple causes, no simple solution

CORVALLIS, Ore. – Amphibian declines around the world have forced many species to the brink of extinction, are much more complex than realized and have multiple causes that are still not fully understood, researchers conclude in a new report.

The search for a single causative factor is often missing the larger picture, they said, and approaches to address the crisis may fail if they don’t consider the totality of causes – or could even make things worse.

No one issue can explain all of the population declines that are occurring at an unprecedented rate, and much faster in amphibians than most other animals, the scientists conclude in a study just published in the Annals of the New York Academy of Sciences.

The amphibian declines are linked to natural forces such as competition, predation, reproduction and disease, as well as human-induced stresses such as habitat destruction, environmental contamination, invasive species and climate change, researchers said.

“An enormous rate of change has occurred in the last 100 years, and amphibians are not evolving fast enough to keep up with it,” said Andrew Blaustein, a professor of zoology at Oregon State University and an international leader in the study of amphibian declines.

“We’re now realizing that it’s not just one thing, it’s a whole range of things,” Blaustein said.

“With a permeable skin and exposure to both aquatic and terrestrial problems, amphibians face a double whammy,” he said. “Because of this, mammals, fish and birds have not experienced population impacts as severely as amphibians – at least, not yet.”

The totality of these changes leads these researchers to believe that the Earth is now in a major extinction episode similar to five other mass extinction events in the planet’s history. And amphibians are leading the field – one estimate indicates they are disappearing at more than 200 times that of the average extinction rate.

Efforts to understand these events, especially in the study of amphibians, have often focused on one cause or another, such as fungal diseases, invasive species, an increase in ultraviolet radiation due to ozone depletion, pollution, global warming, and others. All of these and more play a role in the amphibian declines, but the scope of the crisis can only be understood from the perspective of many causes, often overlapping. And efforts that address only one cause risk failure or even compounding the problems, the researchers said.

“Given that many stressors are acting simultaneously on amphibians, we suggest that single-factor explanations for amphibian population declines are likely the exception rather than the rule,” the researchers wrote in their report. “Studies focused on single causes may miss complex interrelationships involving multiple factors and indirect effects.”

One example is the fungus B. dendrobatidis, which has been implicated in the collapse of many frog populations around the world. However, in some populations the fungus causes no problems for years until a lethal threshold is reached, studies have shown.

And while this fungus disrupts electrolyte balance, other pathogens can have different effects such as a parasitic trematode that can cause severe limb malformations, and a nematode that can cause kidney damage. The combination and severity of these pathogens together in a single host, rather than any one individually, are all playing a role in dwindling frog populations.

Past studies at OSU have found a synergistic impact from ultraviolet radiation, which by itself can harm amphibians, and a pathogenic water mold that infects amphibian embryos. And they linked the whole process to water depths at egg-laying sites, which in turn are affected by winter precipitation in the Oregon Cascade Range that is related to climate change.

The problems facing amphibians are a particular concern, scientists say, because they have been one of Earth’s great survivors – evolving about 400 million years ago before the dinosaurs, persisting through ice ages, asteroid impacts, and myriad other ecological and climatic changes.

Their rapid disappearance now suggests that the variety and rate of change exceeds anything they have faced before, the researchers said.

“Modern selection pressures, especially those associated with human activity, may be too severe and may have arisen too rapidly for amphibians to evolve adaptations to overcome them,” the researchers concluded.

This work was supported by the National Science Foundation and the David and Lucile Packard Foundation. Other collaborators on the study were from the University of Colorado, University of Georgia, University of Pittsburgh, and Pepperdine University.

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55 Responses to Amphibian decline – climate change not the single culprit

  1. ck says:

    What will they say in five years when populations are exploding? All plants and animals surge and decline, and we can’t always figure out why.

  2. Andy G says:

    Cane toads down under don’t seem to be suffering too badly :-(

  3. Brian H says:

    It’s worse than we thought, and we’re not really sure why!

  4. DirkH says:

    Do they enumerate all possible problems an amphibian can encounter in its life to mask the fact that it were the researchers who spread the deadly fungus around the world?

  5. Pingo says:

    If amphibians don’t even taste nice, what is the point of them?

  6. ew-3 says:

    Sounds like the kind of story the MSM will jump all over. /sarc

  7. Theo Goodwin says:

    “The totality of these changes leads these researchers to believe that the Earth is now in a major extinction episode similar to five other mass extinction events in the planet’s history. And amphibians are leading the field – one estimate indicates they are disappearing at more than 200 times that of the average extinction rate.”

    Who in their right mind would write this or publish it? Someone should do an article on Earth’s five great episodes of hysteria. I think the present episode would qualify as number one.

    I used to hang out with some major frog researchers. It seems that frogs suffer catastrophe every few years. The last time I had inside information on an “episode” was the great ozone scare of the late Eighties. It seemed that frogs were dying by the bushel and surely the culprit must be increased UV radiation. Never mind that there was no correlation between the locations of increased UV radiation and locations where frogs were dying.

    Why are none of the scientists publishing hysterical articles about the decline in birthrates among the human populations of Europe and North America? (The decline that I refer to excludes recent immigrants.) Humans don’t count for Greens?

  8. Latitude says:

    Maybe there was something that allowed a population explosion…
    ..and now, different parasites, disease, etc are exploding because of that

    nawwww, every thing was perfect until “scientists” started counting

    and it’s all been down hill since………

    (am broke, send money)

  9. davidmhoffer says:

    ew-3 says:
    April 25, 2011 at 5:42 pm
    Sounds like the kind of story the MSM will jump all over. /sarc>>>>

    Yes it does. Makes me hopping mad just thinking about it.

  10. Tom Bauch says:

    OSU. Let’s see, that’s the university that is kicking out PHD students because their Dad is a conservative politician?

  11. John Cooper says:

    This is such a total crock. Last August I had a clay dam built across our little “branch” here in NC. When the small pond filled up in about a week, I stocked it with 25 channel catfish and 3 lbs. of minnows.

    This spring, the channel cats are no where to be seen, but we have literally thousands of tadpoles, and numerous salamanders. We even have water snakes feasting on the tadpoles. When the snakes appeared, the minnows went into hiding.

    If amphibians are disappearing in Yellowstone, it must be because they’re all here in my pond at the moment.

  12. Werner Brozek says:

    Will this end like the recent salmon story?

    “Three years after government regulators proclaimed the devastated Pacific salmon fishery a federal disaster, commercial fishermen on Wednesday got word to start untangling their nets and greasing their reels.

    The prized king salmon fishery is back, and in numbers that ensure plenty will remain to spawn in freshwater streams this fall, experts say.”

    Read more: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/04/14/MND31J042V.DTL#ixzz1KaRdRpWl

  13. Douglas DC says:

    Dirk H. -exactly. When this was first noted, I remember that there was similar but not as precipitous decline back in the 60’s but cannot remember the name of the researcher who found that there was a fungal vector responsible. I wonder how much is due to the spread by”eco-tourism”?

  14. jcrabb says:

    “The totality of these changes leads these researchers to believe that the Earth is now in a major extinction episode similar to five other mass extinction events in the planet’s history. And amphibians are leading the field – one estimate indicates they are disappearing at more than 200 times that of the average extinction rate.”

    Seems like the Greens were right all along, Human activity is negatively effecting the eco-system that is vital to the existence of the entirety of Humanity, we either change our support system, or the future will belong to a very small population basically living indoors due to a no longer

  15. jae says:

    I live in Oregon and I like OSU, but I am now very sick about some shennanigans there: http://sppiblog.org/news/political-payback-%E2%80%93-oregon-style

    Unfortunately, it now looks like at least part of OSU (including the President) is an arm of the “politically correct” leftist state. So, right now, I would take this “study” with a grain of feces.

  16. jae says:

    Forgot to give reasons for skepticism about “report:” I see no link to the “report” or any indication that it is peer reviewed (even though that means nothing in climate science) or any data or anything else to make me think there is any “beef” there…

  17. jae says:

    OOps, forgive me, a link to a peer-reviewed article is provided. My blindness.

  18. TomRude says:

    Funded by the Packard Foundation… nough said.

  19. jae says:

    Sorry, I’m still recoiling from the firing of Oregon’s State Climatologist, George Taylor for his “failure” to toe the line on AGW. He was also at OSU.

  20. rbateman says:

    Easy PhD’s. Just write something and blame it all on Climate Change and presto, you’re now a Doctor. And don’t forget to pass the Kool Aid.
    What’s the test here?
    When the climate cools off (as in Global Warming causes Global Cooling) the frogs will recover? No, because there is no proof that Global Warming caused Global Cooling due to no way to discern between AGW cooling and natural cooling.
    A perfect hypothesis that has no test. Like Epicycles, they will last 2,000 years.

  21. kuhnkat says:

    BS.

  22. Moira says:

    Maybe they’re starving because the warmists stole all the bugs they could find and put them in their computer models.

  23. John Blake says:

    Over the years, we have learned to dismiss self-serving, invariably spurious Warmist alarums out-of-hand. Vast libraries of coherent, valid data exist worldwide, and rationally interpreting their contents is no more difficult than conducting forensic audits on Wall Street. (Stock-jobbers at least base their scams on market prices.)

    Climate hysterics by now have been so thoroughly and universally discredited that only grant-gobbling college administrators give ‘em the time of day. Having utterly ruined their profession, blighted the careers of any upcoming acolytes caught in Warmist toils, poseurs of Santer’s ilk will eventually sink back into the obscurity they so deserve.

  24. Jimmy Haigh says:

    Ah yes. The heady days of 2008 when they got away with all of the BS they spouted. How they must long for those days again…

  25. Another infuriating example of the uniformitarian weltanschauung in action. One would think that any person who calls themselves an ecologist would be familiar with Lotka-Voltarra equation, or if not mathematically inclined, realize that population numbers are not static. It took only about 1 minute of Googling to find:
    http://www.econ.hit-u.ac.jp/~aokada/kakengame/meeting/workshop/paper/Ms.doc
    which is a paper dealing with application of the Lotka-Voltarra equation to a prey-parasite system which would appear to apply to the amphibian situation. The result of Mougi and Iwasa’s paper is that the parasite host numbers fluctuate to a much greater degree than the parasite numbers. In the case of amphibians, the researchers were, in many cases responible for the transmission of parasitic fungi to amphibians and it will take decades to see the population oscillations that were induced as a result.

    Assumption of amphibian extinction based on not knowing that one is dealing with an oscillatory population is equivalent to predicting that the earths atmosphere will liquify in the near future based on a linear future extrapolation of summer to fall temperatures. The sooner that people realize there are no straight lines in biological systems the better off we will be.

  26. Dishman says:

    Something is killing frogs in Yellowstone?

    I’d be more concerned about changes in local chemistry than AGW. It is, after all, an active VEI 8 volcano.

  27. DesertYote says:

    I could have sworn that I have been able to find thriving populations of every reptile and amphibian native to just about every place that I have lived the past 30 years. I must have been mistaken.

    BTW, most of the so called population studies that have been done, are designed to produce specific results that yield data to support the particular agenda driving the study. For example, selecting lakes that have just been stocked with bass!

  28. Huth says:

    Kool Aid makes good dye.

  29. Julian Flood says:

    “Sounds like the kind of story the MSM will jump all over. /sarc>>>>”

    “Yes it does. Makes me hopping mad just thinking about it.”

    You can bet it will spawn a hundred horror stories.

    (Sorry, sorry…)

    JF

  30. Martin Brumby says:

    When I was a kid, there was a scare that myxomatosis would make all rabbis extinct. (Farmers had to put a brave face on this news).

    Nowadays, I bet no-one on here has ever seen a rabbit. They are SO rare. /sarc.

  31. Katherine says:

    “…human-induced stresses such as habitat destruction, environmental contamination, invasive species and climate change, researchers said.”

    Right. Climate changes. Always does. But of course it’s “human-induced.” Heh. It’s from OSU. That says it all.

  32. dave Harrison says:

    It may be that there is a real threat to amphibians and that this is caused by human activity and is reversible, but the problem with automatically attributing all things bad to ‘global warming’ is that it stops proper investigation of other possible underlying causes. Remember the decline in penguin numbers which turned out to be because of the tagging techniques used?
    There are many possible causes for amphibian decline, including chemical contamination of the environment or the spread of disease by well-meaning researchers – as happened in the case of frogs in some remote areas. Attributing everything to climate change – with no scientific evidence – can only inhibit the study of the real cause and possible prevention.

  33. Al Gored says:

    DirkH says:
    April 25, 2011 at 5:36 pm

    Do they enumerate all possible problems an amphibian can encounter in its life to mask the fact that it were the researchers who spread the deadly fungus around the world?”

    They definitely appear to be doing, or trying to do, just that.

    Love this little trick…

    “One example is the fungus B. dendrobatidis, which has been implicated in the collapse of many frog populations around the world. However, in some populations the fungus causes no problems for years until a lethal threshold is reached, studies have shown.”

    No mention of how it was spread. And they try to gloss over the point that it kills them. Yes, first it reaches a lethal threshold, and then they die.
    Duh. But it implies there is something else going on. And then this quick switch:

    “And while this fungus disrupts electrolyte balance, other pathogens can have different effects…

    Yes… so… look over there! Forget that silly fungus. After all, it doesn’t kill anything until it reaches a lethal threshold.

    So, no doubt, this is a spin-o-rama. For most amphibian populations I am familiar with it is or was the fungus. The herpetologists I know now all have multiple pairs of gumboots and waders and are extremely careful about what they are carrying now… and that was based on what they had accidentally done before.

    By the way… business has never been better for herpetologists.

  34. George Lawson says:

    So a few frogs are missing from Yellowstone Park “which leads us to the conclusion that amphibians are going extinct around the World” I wonder who did the Worldwide research. “An enormous rate of change has occurred in the last 100 years” So recent global warming can’t be the problem. “The earth is now in a major extinction episode” It’s amazing what conclusions a biology graduate student can deduce from a few missing frogs in Yellowstone Park. ” The rate of change is unprecedented in 400 million years” Our computer model tells us so. ….. This sounds like a good one for the Australian government to buy into.

  35. John Marshall says:

    I ask again- How did these species survive previous warmer periods of which there were many in the past?

  36. Thomas R says:

    There are probably numerous reasons why amphibians are in decline:
    Waste water contains medicinal residue from humans and agriculture, chemicals from cosmetics, food, industry and heavy metals from all of the above… These creatures are vulnerable to changes in water pH and temperature as well, since they spend much of their life in or near rivers, ponds and lakes.

    In addition, wetlands, the habitat for many species, is threatened from many sides: Industry in need of water is one of the big ones, but all over the world various development projects fail to see how important these areas are.

    Global climate change or not; here are some indisputable facts:
    We are approaching 7 billion people on this planet, that is an increase of more than 400% in only a century. At the same time our spending and ecological footprint has increased as well. I dare not suggest a number, but think about the difference between life in the early 1900s and now…

    The result:
    We have an effect on our surroundings, and for animals evolved over millions of years, the changes cause imbalance and harm. These changes will also affect us, since we share the ecosystem, we live on the same planet.
    It is time to clean up our act. It is no longer our children and grandchildren that will suffer from our mistakes; The changes are now so rapid, most of us will experience them in our lifetime.

  37. Viv Evans says:

    Interesting, innit like – it’s always Us Humans who are guilty, one way or another …

    So apparently all was well in amphibian-dom, no pathogens, no climate change, no nothing until Us Humans turned up. A bit like the Garden Eden until that thing with the snake and the apple …

    One also wonders if these scientists actually made the effort to look at some research into population dynamics, or into ecology.
    I bet not one of them ever heard of Charles Elton,never mind reading his papers and books. But then, that was such a looong time ago – and nothing that happened before last Tuesday actually counts…

  38. View from the Solent says:

    Boris Gimbarzevsky says:
    April 25, 2011 at 8:38 pm
    One would think that any person who calls themselves an ecologist would be familiar with Lotka-Voltarra equation.
    ——————————————————————————–
    Indeed! It even appeared early in my 1st-year undergrad maths.

  39. wsbriggs says:

    I for one, think that a careful forensic look at the clothing and other apparel of the researchers is in order. Just like Sudden Oak Death Syndrome, I suspect that biologists and naturalists are carrying in the pathogens. I’ve rarely seen a naturalist act as if they were in a clean room. When traveling among continents, it’s really easy to carry things from one spot to another, just look at the SIDS, Swine Flu, Bird Flu, etc. When more naturalists are seen in the same kind of garb used with the oil spill last year, not when they’re doing remediation, but just to protect the environment from foreign pathogens.

  40. Mick J says:

    Geoffrey Lean, eco writer of the London Telegraph ran a related story about amphibian decline and stated the export numbers of Frogs in Indonesian as a backstop to his claims. Needless to say there were no references.
    http://www.telegraph.co.uk/earth/earthcomment/geoffrey-lean/8469051/Trouble-in-the-air-for-Britain.html About half way down the article for the Frog story.
    A few minutes search turns up a 2005 thesis that maintains that Frog populations are essentially stable in spite of said trade. My post to his article.
    ~~~~~~~~~~~~~~
    Geoffrey reports on the claimed fate of frogs and makes a number of claims with large numbers thrown in for good measure but with no references again. It did not take long to find a study dated 2005 that examined the state of frog populations in Indonesia. Perhaps he could provide references for the habitat loss (bio-fuels?) and climate change effects and impacts on these species.

    From the thesis:
    9.6 Conclusions and Recommendations
    My study suggests that the current levels of harvest of F. cuncrh’ora and F. limnocharis—iskandari complex are sustainable. The impact of harvesting on L. inacrodon is unclear. Current levels of harvest appear likely to affect L. macrodon populations more than F. cancrivora, however, there is a need to do more research on the population biology and ecology of this species.
    Although I conclude that there is no justification for including the harvested species in the Red List or in the CITES appendices. the scientific authority (I.IPl) should regularly monitor the trade. Monitoring of the frog leg trade should occur not only in Java hut also in the other main islands, especially Sumatra. From the export statistics, the centre of exportation in Sumatra is in Medan, thus the monitoring in Sumatra should begin from Medan and surrounding North Sumatran areas. Monitoring should include collection of data on species harvested, size harvested, the spatial and temporal patterns of harvest, and the population ecology of the species harvested.

    Study at http://eprints.jcu.edu.au/1118/2/02whole.pdf

  41. Allanj says:

    I have a pond in my yard in Northern Virginia. For ten years the frogs were unpleasantly loud each summer evening. Two years ago they disappeared. I suspected my neighbors did something to my pond water and then I read about the worldwide fungus. After two years of peace and quiet the frogs are back, louder than ever.

    I don’t mind the frogs. After all they do eat insects. But does anyone know how to make them shut up?

  42. Pull My Finger says:

    They really need to have climate “scientists” take statistics classes. A small sample from a small corner of a small part of a state really doesn’t mean jack squat in any larger context.

    Really, this is more “natural philosophy” than science where these d-nozzles sit around and discuss what bed time boogie man story will garner them the most grant money.

  43. Magnus says:

    Wow, that’s serious. I’m buying a round of carbon credits. Anyone?

  44. pRadio says:

    Man will be exstinct in ~100 years!
    At the current Death rate we will all be gone. My study proves it.

    What? birth rate? Oh no, this study only looks at Death rate………

  45. UK Sceptic says:

    The frogs in my wildlife pond aren’t in decline because the randy little so and so’s spawned twice last year. Believe it or not I had tadpoles swimming around under the ice on Christmas day. But then, I also had a tortoiseshell butterfly hatch in my bathroom the same day, probably due to the central heating. It sure as hell wasn’t down to the global warming forming fluffy white drifts outside. The spring brood of taddies are hatched and swimming so no shortage this year either.

  46. Mike M says:

    Rate of change? What change? If there is a dramatic difference in the reproductive rate of any species between now and in 1980 then global temperature cannot possibly be the cause because we are right back to the same global temperature.

    So given no net change of global temperature in 30 years, the TINY amount of fluctuation that has occurred within that time and that these critters survived all the other swings of global temperatures in the past I think blaming climate is croaking up the wrong tree. IF it is us then I am suspicious of things like MTBE or insecticides etc. I remember encountering so many baby toads on the lawn back in the early 60’s that I couldn’t … well … there were a LOT of them; a lot more than now.

    But BTW, the peepers is peeping just fine this Spring in Massachusetts – right on time.

  47. TomB says:

    “With a permeable skin and exposure to both aquatic and terrestrial problems, amphibians face a double whammy,…

    Since you’re talking about a species that can live both in and out of the water, doesn’t that actually double its chances of survival? The above strikes me as a statement just brimming over with confirmational bias. Or, as Arnold Rimmer would put it, “Wrong! Wrong! Just brimming over with wrongability.”

  48. PB-in-AL says:

    “…are being killed in Yellowstone National Park. The predator, Stanford researchers.”

    I think it should just end there. It makes it much more interesting, and plausible. ;)

  49. Dave Bob says:

    Mike M says:
    “Rate of change? What change? If there is a dramatic difference in the reproductive rate of any species between now and in 1980 then global temperature cannot possibly be the cause because we are right back to the same global temperature.”

    But Mike, that’s just proof that things are even morely more worser than we thought we were thinking!

    If a temperature increase of, well, zero can have such a dramatic effect, imagine the ecological cataclysm from a 2 degree rise!

  50. Mike M says:

    Dave, you’re probably right because I wasn’t thinking of what I thought.

    Then again, maybe the critters are suffering from not enough climate change? Gaia was trying to cool earth down rapidly but our CO2 emissions countered her intentions. So now she’s obviously punishing us for that by making us feel guilty believing we are responsible for killing off frogs when in fact she’s the one who’s been doing it all along. Women….

  51. Jimbo says:

    The researchers are spreading diseases via their boots, tyres and hands onto the amphibians!!!!!

  52. George E. Smith says:

    “”””” CORVALLIS, Ore. – Amphibian declines around the world have forced many species to the brink of extinction, are much more complex than realized and have multiple causes that are still not fully understood, researchers conclude in a new report. “””””

    “”””” still not fully understood, researchers conclude “””””

    Why don’t you hold your “conclusions” until your subject IS fully understood ” That would be more in keeping with the scientific method. Science does not advance by publishing the results of “gee I dunno” studies, and concluding the subject is not understood.

    Newspaper reporters with a deadline to meet are trained to shoot from the hip, and issue retractions (maybe) later. anything to get there first; right or wrong; just be first.

    So those OSU scientists in cultivation, are being trained well in the fine art of being first; regardless of truth.

  53. spangled drongo says:

    Chitridiomycosis is one fungus that has been doing bad things for a long time and often introduced by scientists as Dirk H and Douglas DC said.

    Nothing to do with AGW.

    http://en.wikipedia.org/wiki/Chytridiomycosis

  54. Mike M says:

    Jimbo says: .. ROFLMAO!

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