Monarch Migration Predicted to be Extinct within 16 years

Patrick Foley patfoley at
Tue Oct 7 10:50:14 EDT 2003


Is it possible that without Brower's constant harping, the Monarch's 
wintering habitat in Mexico would be more threatened than it is today?

Did Brower blunder? Or did he warn? Is the habitat in Mexico secure now? 
Brower gets ten more years on his "blunder", based on the quote you 
link. And note, Brower is not claiming that Monarchs will be extinct in 
ten years, he is claiming that the Eastern migratory phenomenon is 
likely to be extinguished. I think Brower may be wrong, partly because 
he was right to push for the protection of the overwintering sites. But 
I also think that the migratory phenomenon is more fragile than you do. 
At some point of overwintering mortality in Mexico, the Eastern monarch 
population is going to be under strong selection to avoid it.

If you are so concerned with getting the research right, why not do some 
research into that? You certainly have a right to your own constant 
harping (as does Brower), but are you helping clear up the ecology and 
evolution of this organism, or are you just pissing people off?

Obviously you know a lot about the Monarch, and your posts do provide 
some interesting insights. However you will get more respect if you 
treat others with more respect, and if you are scrupulous to avoid 
biasing your insights.

It is not the business of scientists to be infallible. We leave that to 
others. At the end of the day, Brower will surely be wrong about some 
things and right about others. And we will know a lot more baout the 
Monarch. And maybe the Eastern migratory phenomenon will be more secure. 
If his conservation organization also is rolling in money (which I 
greatly doubt), this is the least of our worries.

Enjoy the historical recall vote today!

Patrick Foley
patfoley at

Paul Cherubini wrote:
> Stan wrote:
>>I have to question what Dr. Brower meant by "...normal..."  If his
>>"normal" is a 10 year moving average,  and if (as an example) the
>>average 11 years ago was three times what it was last year, saying it is
>>"slightly above normal" could cause one to misinterpret this to mean the
>>Monarch is doing very well.
> The total size of the monarch overwintering population in Mexico
> is determined by measuring the total forested area occupied by the 
> butterflies.  Over the years, the total forested area occupied has been found
> to range from 2 - 18 hectares and the average has been about 8 hectares 
> (= 20 acres).
> During the 2001-2002 overwintering season, the total area occupied
> by the monarchs was found to be 9.6 hectares, so that is why Dr. Brower
> said the size of monarch overwintering population was "slightly above 
> normal".   
> Back in 1988-1991, however, Dr. Brower 
> was predicting the extinction of the monarch migratory phenomenon
> as early as the year 2000.  For example, here is what Dr. Brower
> wrote in the journal "American Zoologist" in 1991:
> In spite of this blunder, Dr. Brower continues to predict the 
> extinction of the monarch migration, but has moved the date of
> final demise up to the year 2019.  
> Paul Cherubini
>  ------------------------------------------------------------ 
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