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

[Stanley A. Gorodenski]

Paul Cherubini wrote:

>Pat wrote:
>  
>
>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
>  
>

I looked at photos and animations at your web site. The first thing I 
notice is that your oldest photo for comparison is 6 years after the 
Brower animations (does Brower refer to these as animations? It seems 
like a poor choice for a descriptive word). Thus things are not strictly 
comparable if there was a significant amount of thinning and elimination 
of the forest between 1984 and 1990.
Second, you appear to be referring to something different. Brower refers 
to the 'El Rosario Reserve'. You are referring to the 'El Rosario 
Sanctuary'. Are these the same things? If not, then your photos may be 
biased by picking and choosing what you want to show and not showing the 
degree of degradation that has taken place in the 'Reserve'.
Third, Donna Brunet raises a good point in that you are presenting off 
to the side photos of the forest which may hide the thinning that might 
have taken place. They are not overhead like the Brower map. I admit, 
the forests look pretty dense, but photos can be misleading. Once I saw 
a 1963 Comet for sale on the web. It looked like new. It looked 
fantastic. The actual car was drastically in the opposite direction.
Stan


 
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