Mountain Pine Beetle – climate is the key

The mountain pinebark beetle Dendroctonus ponderosae is a small beetle native to North America from Mexico to British Columbia. This species plays an important ecological role in pine forests by removing old, weak trees, facilitating the growth of saplings. They do this by laying their eggs under the bark of old stressed trees. The larvae, after hatching eat the wood contributing to the tree’s decline. Trees will respond to egg-laying by exuding sap which expels the eggs but also weakens the tree and opens it to infection by pathogenic fungi. In the normal course of things, the ecosystem functions with a high level of predictability.

Recently, pine beetle outbreaks have been more intense, longer in duration and have covered larger and larger areas, resulting in large swathes of mature, usually healthy trees dying. It has been hypothesised that human-induced climate change has been partially responsible. A number of isolated studies in various locations have added weight to that hypothesis. A new study  published in the journal Ecology investigates multiple outbreaks over large spatial areas and models these against known climate and weather variables. The authors report that climate is affecting weather patterns resulting in longer droughts, altered rainfall and increased temperature. These in turn are acting as stressors on mature trees,increasing opportunities for beetles to reach plague proportions. 

More and more studies of this sort will be comingout in the next few years, adding further weight to the copious evidence for biological effects of climate change that already exist.

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Filed under Climate Change

15 responses to “Mountain Pine Beetle – climate is the key

  1. john byatt

    The TCS Geoff tells us this morning that a Nature study confirms that sceptics like him have a higher understanding of climate change than those more concerned,

    here is the gist

    Seeming public apathy over climate change is often attributed to a deficit in comprehension. The public knows too little science, it is claimed, to understand the evidence or avoid being misled1. Widespread limits on technical reasoning aggravate the problem by forcing citizens to use unreliable cognitive heuristics to assess risk2. We conducted a study to test this account and found no support for it. Members of the public with the highest degrees of science literacy and technical reasoning capacity were not the most concerned about climate change. Rather, they were the ones among whom cultural polarization was greatest. This result suggests that public divisions over climate change stem not from the public’s incomprehension of science but from a distinctive conflict of interest: between the personal interest individuals have in forming beliefs in line with those held by others with whom they share close ties and the collective one they all share in making use of the best available science to promote common welfare.

  2. john byatt

    That was from Nature not from geoff

    • Yup I got that. It was too coherent.

      • john byatt

        Obviously, I looked at the test as well, about grade 1 high school level. still chuckling over that comment mike,

        • I’ll do a new post about this and maybe invite Geoffrey to have a go at answering a few questions that I devise that would determine the difference between scientifically and numerically literate and illiterate people, especially as it pertains to climate science. Knowing whether the Earth goes around the sun or vice versa doesn’t point to scientific literacy at all. It indicates whether someone is a moron or not.

      • john byatt

        I would put it down to educated and non educated, the non educated not suffering from DK would accept the scientific conclusions that they should be concerned.

  3. john byatt

    Another case of ignorance from the Climate sceptics party

    The University of Hawaii researcher reports that the rural lagoon shore of Majuro Atoll has been predominantly eroding, but that the ocean-facing shore has been largely accreting, and at a much faster rate. In addition, he finds that “shoreline change within the urban area of Majuro has been largely driven by widespread reclamation for a mix of residential, commercial and industrial activities.” Thus, “despite a rising sea level,” he finds that “the landmass of Majuro has persisted and, largely because of reclamation, increased in size.”

    What it means
    Ford concludes by noting that as an atoll population increases, “further demands are placed on the limited land available,” and he says that in the case of Majuro Atoll, “it is likely that land reclamation will continue to satisfy this demand,” noting that “the notion that sea level rise is a singular driver of shoreline change along atolls is spurious,” while stating that “adopting such a notion is an impediment to the sustainable management of coastal resources within urban atolls.”
    Inhabitants of Tuvalu (and other island states) … take note!

    “Inhabitants of Tuvalu (and other island states) … take note!”

    Funafuti height above sea level is about one metre, highest point about four metres, basically the whole island is crushed coral. and geoff’s fix is to reclaim land, this bloke votes!

  4. john byatt

    The sceptic morons at just Geoff’s justgrounds Galileo group have themselves in a tiss, Germany it seems is dumping renewable energy, wondered where that load of crap came from,

    The exact opposite of course is true


  5. john byatt

    So where did the Justground idiots get this garbage?

    Geoff brown posted this,

    Reply by Geoff Brown on Monday
    Germany has woken up from a green slumber and looks like scrapping all their green energy policies – now we have to wake up to the hoax pushed by the Green Gillard Government see LINK

    the LINK then goes to his TCS blog which then links to the GWPF which then cherry picks a Morgenpost article,, story slightly changes as it goes through each of the echo chambers.

    Sceptics? gullible fools more like it .


  6. Hi Mike,

    Thanks for choosing to follow my blog. I do not always reciprocate, but in your case, I will definitely do so. Judging by the content of your ‘About’ page, you might enjoy reading my posts on the ‘marketplace of ideas’ fallacy, Ben Goldacre’s Bad Science, and David Aaronovitch’s Voodoo Histories

    As for the Mountain Pine Beetle, I have Professor Iain Stewart to thank for alerting me to this last year in Future Earth (view from 8min38secs):

    Keep up the good work.

    • Hi Martin

      Welcome aboard. I can’t promise I’ll be overly busy with my blog due to increasing work commitments but I’ll try and keep it fresh. Being an insomniac helps a bit.