CANBERRA, Australia, May 7, 2008

Koalas Feeling Heat From Global Warming

Carbon Dioxide Pollution Is Damaging Eucalyptus Plants Needed For Survival

  • A researcher says koala numbers are under threat from carbon pollution in the atmosphere because the greenhouse gas saps nutrients from eucalypt leaves with are the animals' only source of food.

    A researcher says koala numbers are under threat from carbon pollution in the atmosphere because the greenhouse gas saps nutrients from eucalypt leaves with are the animals' only source of food.  (AP Photo/Rick Rycroft)

  • Fast Facts Australia

    Learn about the people, economy and history.

  • Interactive Global Warming

    The greenhouse effect, a look at the Kyoto Protocol and a history of the Earth's climate.

(AP)  Koalas are threatened by the rising level of carbon dioxide pollution in the atmosphere because it saps nutrients from the eucalyptus leaves they feed on, a researcher said Wednesday.

Ian Hume, emeritus professor of biology at Sydney University, said he and his researchers also found that the amount of toxicity in the leaves of eucalyptus saplings rose when the level of carbon dioxide within a greenhouse was increased.

Hume presented his research on the effects of carbon dioxide on eucalyptus leaves to the Australian Academy of Science in Canberra on Wednesday.

The researchers found that carbon dioxide in eucalyptus leaves affects the balance of nutrients and "anti-nutrients" - substances that are either toxic or interfere with the digestion of nutrients.

An increase in carbon dioxide favors the trees' production of carbon-based anti-nutrients over nutrients, so leaves can become toxic to koalas, Hume said.

Some eucalyptus species may have high protein content, but anti-nutrients such as tannins bind the protein so it cannot be digested by koalas.

Hume estimated that current levels of global carbon dioxide emissions would result in a noticeable reduction in Australia's koala population in 50 years due to a lack of palatable leaves.

Out of more than 600 eucalyptus species in Australia, koalas will only eat the leaves of about 25, Hume said. Changing the toxicity levels in the trees could further reduce the varieties that koalas find palatable, he said.

"Koalas produce one young each year under optimal conditions, but if you drop the nutritional value of the leaves, it might become one young every three or four years," Hume said.

Hugh Tyndale-Biscoe, a marsupial physiologist, described Hume's predictions of declining koala numbers as speculative but credible.

Eucalyptus leaves already have little nutritional value, he said, and koalas have adapted to their poor diet by sleeping to conserve energy.

"It's a very precarious existence," Tyndale-Biscoe said. "They basically sleep for 20 hours a day and then they've got four hours to do everything else - occasionally eat a leaf and maybe once a year go after another koala" to mate.

Tyndale-Biscoe said koalas had already disappeared from parts of Australia but remained plentiful in others and were unlikely to be wiped out by climate change. They already have been displaced from the most nutritious trees on the most fertile land by the spread of farms and suburbs, he said.

© MMVIII The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.
Share:
  • Share
  • Yahoo! Buzz
  • Mixx
Add a Comment See all 32 Comments
by libh8er May 9, 2008 1:52 PM EDT
They should relocate to the northern hemisphere.....coldest April in 10 years. Perhaps Koalas are going to join the ranks of the Pandas.....they have been chosen for extinction (or evolution to he next astral plane.)
Reply to this comment
by octavianfdlr May 9, 2008 9:54 AM EDT
From the spin standpoint, this article is absolutely fascinating! CBS starts with a subtitle stating "Carbon Dioxide Pollution Is Damaging Eucalyptus Plants Needed For Survival." The lead sentence is then "Koalas are threatened by the rising level of carbon dioxide pollution in the atmosphere because it saps nutrients from the eucalyptus leaves they feed on, a researcher said Wednesday."

Notice that the researcher did not say that the eucalyptus leaves were "damaged," but only less nutritious. Let us examine the issue:

In the first place, Supreme Court orders notwithstanding, carbon dioxide is not a pollutant from the standpoint of a green plant (e.g. Eucalyptus sp.), but an essential nutrient. The green plant gets its food from the action of light and enzymes (proteins) in chloroplasts on carbon dioxide. The more carbon dioxide, the less enzymes are needed. From the standpoint of an eucalyptus predator (e.g. koala) the leaves become less nutritious. On the other hand, the overabundance of photosynthates would enable the eucalyptus to produce greater quantities of chemical defenses, the "toxins" (from the standpoint of a predator) mentioned in the article.

The point is, that the eucalyptus is in no way damaged by any of this. It''s better off.

Imagine that the US started making much greater use of wind, solar, and nuclear power. Who would describe this phenomenon as "sapping the US of imported petroleum?"
Reply to this comment
by octavianfdlr May 9, 2008 7:05 AM EDT
"Gaye5

Thanks for the absolute dribble but that debate is long over. The sane world has already acknowledged that global warming is happening and is man-made."

Posted by singingrick at 08:17 AM : May 08, 2008

=-=-=-=-=-=-=-=-=-=-=

That''s right, singinrick! Hide your head in the sand (like you alarmists have been saying the skeptics do) the moment you find out that the SCIENTISTS are agreeing with the skeptics.

---

But back to the point: this article is not about temperature effects (a/k/a Global Warming) but about the chemical effects of increased carbon dioxide (a necessary nutrient for green plant growth) on the chemical makeup of certain green plants.

---

BTW, the word is drivel. LOL
Reply to this comment
by singingrick May 8, 2008 11:17 AM EDT



Gaye5


Thanks for the absolute dribble but that debate is long over. The sane world has already acknowledged that global warming is happening and is man-made.





Reply to this comment
by gaye5 May 8, 2008 9:32 AM EDT
And more..
Marohasy: "That''s right ... These findings actually aren''t being disputed by the meteorological community. They''re having trouble digesting the findings, they''re acknowledging the findings, they''re acknowledging that the data from NASA''s Aqua satellite is not how the models predict, and I think they''re about to recognise that the models really do need to be overhauled and that when they are overhauled they will probably show greatly reduced future warming projected as a consequence of carbon dioxide."
Duffy: "From what you''re saying, it sounds like the implications of this could be considerable ..."

Marohasy: "That''s right, very much so. The policy implications are enormous. The meteorological community at the moment is really just coming to terms with the output from this NASA Aqua satellite and (climate scientist) Roy Spencer''s interpretation of them. His work is published, his work is accepted, but I think people are still in shock at this point."

If Marohasy is anywhere near right about the impending collapse of the global warming paradigm, life will suddenly become a whole lot more interesting.
Reply to this comment
by gaye5 May 8, 2008 9:29 AM EDT
More of the article.
Duffy: "Is this a matter of any controversy?"
Marohasy: "Actually, no. The head of the IPCC (Intergovernmental Panel on Climate Change) has actually acknowledged it. He talks about the apparent plateau in temperatures so far this century. So he recognises that in this century, over the past eight years, temperatures have plateaued ... This is not what you''d expect,

Duffy: "Can you tell us about NASA''s Aqua satellite, because I understand some of the data we''re now getting is quite important in our understanding of how climate works?"

Marohasy: "That''s right. The satellite was only launched in 2002 and it enabled the collection of data, not just on temperature but also on cloud formation and water vapour. What all the climate models suggest is that, when you''ve got warming from additional carbon dioxide, this will result in increased water vapour, so you''re going to get a positive feedback. That''s what the models have been indicating. What this great data from the NASA Aqua satellite ... (is) actually showing is just the opposite, that with a little bit of warming, weather processes are compensating, so they''re actually limiting the greenhouse effect and you''re getting a negative rather than a positive feedback."

Duffy: "The climate is actually, in one way anyway, more robust than was assumed in the climate models?"
Reply to this comment
by gaye5 May 8, 2008 9:28 AM EDT
rheola the liberal governmnent which in case you dont know is right winged, didnt do much about the so called global warming simply because many of them didnt believe the alarmists. However, for you information, here is a portion of an interview which you can look up yourself, the Australian reported..
Climate facts to warm to
Christopher Pearson | March 22, 2008
CATASTROPHIC predictions of global warming usually conjure with the notion of a tipping point, a point of no return.

Last Monday - on ABC Radio National, of all places - there was a tipping point of a different kind in the debate on climate change. It was a remarkable interview involving the co-host of Counterpoint, Michael Duffy and Jennifer Marohasy, a biologist and senior fellow of Melbourne-based think tank the Institute of Public Affairs. Anyone in public life who takes a position on the greenhouse gas hypothesis will ignore it at their peril.
Duffy asked Marohasy: "Is the Earth still warming?"

She replied: "No, actually, there has been cooling, if you take 1998 as your point of reference. If you take 2002 as your point of reference, then temperatures have plateaued. This is certainly not what you''d expect if carbon dioxide is driving temperature because carbon dioxide levels have been increasing but temperatures have actually been coming down over the last 10 years."
Reply to this comment
by gaye5 May 8, 2008 9:13 AM EDT
and rheola, if you had really read the article that I pasted in there you would have seen that the article was not my words but the writings of....

Study of the orbital mechanics of the solar system in the 1970s led Russians to believe the Earth was about to cool and we should prepare quickly because it will be catastrophic......and

As the sun goes even quiter and January, 2008 saw the greatest year to year temperature drop ever (128 years of NASA GISS data), it is clear cooling needs to be considered as a very plausible future.
Reply to this comment
by gaye5 May 8, 2008 9:07 AM EDT
rheola, we have had a very cool summer compared to the last 28 years that we have been living in Australia.. Even here in Brisbane where it is generally stinken hot it has been lovely...and yes, I was not born here, we come from NZ, which you might not know is approx two and a half hrs plane trip from Australia..and where it is much cooler..We know here that when the trees in the rain forests about an hrs drive north starts to die that we are in big trouble, and as yet they havent started dying. however a older lady who lived in the area said on talk back that the rain forests did suffer greatly about 50 years ago from lack of rain, but wait we didnt have global warming then..
Reply to this comment
by jimfinster May 8, 2008 1:11 AM EDT
The Koala and the Panda (neither is a bear), should arm wrestle to see which is the stupidest animal on the planet; one only eats 25 out of several hundred species of tree leaves, and the other one only eats a few out of hundreds of species of bamboo; talk about dumb critters; neither one of them deserves to survive if they are that stupid.

Posted by Seafang


I can think of one species even dumber - humans! What other species would destroy and pollute the very environment in which they must live?

And the dumbest of the dumb? Those that deny it is even happening !




Reply to this comment
See all 32 Comments

Exclusive Webshow

Author Thomas Friedman on Obama's Afghanistan plan and the war on terror. Watch Now

Latest News
News in Pictures
Scroll Left Scroll Right
  • Verdict In Italy Verdict In Italy

    American Amanda Knox and Italian ex-boyfriend Found Guilty in Murder of British Student

  • Day in Pictures Day in Pictures

    A Glimpse at the Day's News as Seen Through a Camera Lens

  • Decade in Photos Decade in Photos

    A Look Back at the Events that Rocked the Headlines in the 2000's

  • Jaimee Grubbs Secret Pics Jaimee Grubbs Secret Pics

    Los Angeles Party Girl Quick to Claim Tiger Affair, But Not So Fast To Reveal Criminal Past

  • Celebrity Circuit Celebrity Circuit

    Aishwarya Rai Photo Shoot:,"Lovely Bones" Premiere, Reese Witherspoon and Penelope Cruz

  • "Nine" Debuts in London

    Star-Studded Film Has a British Red Carpet Premiere

Connect with CBS News

Stay connected with the CBS News using your favorite social networks and online news applications: