FW: [leps-talk] Re: Monarch Extinction (substantial evidence?)

[Paul Cherubini]

Pat wrote:

> The doomsayers are may be wrong, but they appear to have
> quantitative evidence about Monarch habitat loss. Paul is
> raising interesting points, but he is not dealing with the
> quantitative analysis Brower's team gives us.

Pat, Brower's team used aerial photographs to produce a computer
animation which estimated changes in forest canopy cover at the
monarch reserves between 1971 and 1999.

These animations suggest a substantial loss of forest cover.  However,
when the animations are paired side by side with actual photographs
of the forest cover, one sees no noticable loss of forest cover.
Example:  here is the animation of the changes in forest cover at
the El Rosario Reserve presented side by side with actual photos of
the reserve http://www.saber.net/~monarch/animation2.jpg

The butterflies at the El Rosario reserve are still clustering in the
same areas of the forest today that they used in the 70's & 80's and
are still surviving well.  So the Brower's team claim the El Rosario
Reserve is now "degraded" amounts to speculation.
It follows that the Brower team's predictions of the extinction of
the monarch migration by the year 2010 or 2020 is based on 
speculation, much like Brower's failed 1990 prediction that the 
migration would become extinct by 2000 or 2010.

Now if Brower could come up with case history evidence of how
forest thinning caused the monarchs to abandon a formerly used
reserve in Mexico or caused the monarchs to suffer alot more
mortality during storms and freezes, then it would be a different
story. But so far the Brower team has not come up with 
case history evidence. Just animations and speculation.

Paul Cherubini

 
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