Fw: Interesting ...

Paul Cherubini monarch at saber.net
Wed Apr 17 18:48:01 EDT 2002

Mark Deering wrote:

> As to your divergence to others statements and thoughts 
> on Monarch populations, why do you not care if so many 
> Monarchs died in the first place? Would not the population
> have been that much BETTER had they lived?

I agree Mark, but I am unaware of any case history evidence 
that indicates there is a certain forest canopy structure or 
density that can prevent mass monarch mortality during severe 
winter storms in either Mexico or California.  

For example, lets look at what happened this past winter.  On Feb 
14, 2002 Elizabeth Howard announced the following sensational 
news on the Journey North website:

Single Storm Kills Over 75% of Eastern North America¹s Migratory Monarchs
"Sierra Chincua Sanctuary: 74% of the butterflies were killed 
El Rosario Sanctuary: 80% of the population was killed. Significantly, 
these two huge colonies are the winter sanctuaries of 2/3 of eastern
North America¹s migratory butterflies. The other 1/3 of the butterflies
are spread among other smaller sites in the vicinity.  While scientists 
have not yet visited these outlying sites, mortality rates are feared to
be similar because the sites are small, their forest habitat is less pristine,
and because the rain and cold were prolonged in the region."

Now the crucial question at hand is did more monarchs die at
these outlying colonies "because the sites are small, their forest 
habitat is less pristine, and because the rain and cold were prolonged
in the region" ?? 

Mark, In fact just the OPPOSITE occured. After the storm Dr. Robert 
Cook, a Wildlife Biologist for the National Park Service visited the 
Cerro Pelon overwintering site in Mexico (one of the "outlying sites") 
and reported the following to Chip Taylor:

"While the reports of the high mortality at El Rosario and Sierra 
Chinqua are certainly cause for grave concern, I wanted to let you 
know that this extreme mortality event may not have affected all 
overwintering sites. We saw no evidence of die-off, there was only 
what I would consider "background mortality", evident in the relatively
 small numbers of dead butterflies we saw on the ground."

Likewise Mark, subsequent visits to both the Herrada colony
(another "outlying colony") as well as Cerro Pelon by monarch biologist 
Dr. Bill Calvert revealed no evidence of mass mortality.  

Predictably, there was no media coverage of the fact that
there was alot LESS monarch mortality at the southern outlying colonies
where there was a LESS pristine forest!!  Instead, in a Feb. 2000 
press release the World Wildlife Fund reported:

"The forest canopy was too thin to protect the delicate monarchs from 
the rain and cold weather last month," said Brower,  the U.S.'s leading 
monarch expert. "A healthy and intact forest serves both as an umbrella 
and a blanket that protects the monarch colonies from the wind, rain and 

Mark, something else occurred this winter in Mexico that
didn't receive media coverage and shatters the politically appealing belief 
that an intact forest can protect the monarchs from mass mortality during 
storms and freezes in Mexico.  

At the time the storm hit in January, the El Rosario colony was split into 
two subcolonies.  One colony was formed in the usual location just above 
some farmed fields and the other was formed further up the mountain, beyond 
a ridge where tourists normally are not allowed to go.  Monarch mortality 
was much greater at the upper colony according to Chip Taylor.  

Now the irony is that that just a few years ago Lincoln Brower had told us  
ago that he considered the forest at this upper colony "more intact" than 
the forest at lower colony next to the farmed fields.

Specifically,  here's what Lincoln Brower told the NY Times reporter 
in Sept. 2000 http://www.biotech-info.net/wintering_grounds.html

"Dr. Brower said that in one region where there has always been 
a large monarch colony, development has encroached to the point 
that the once remote roosts of monarchs are now dangling in trees
right next to farm fields. This winter, the butterflies startled 
biologists by abandoning the site, moving over the mountains to a 
more intact forest area -- an increasingly rare commodity -- that 
they had never used before."

My point here Mark is that there was alot LESS mortality this winter 
at the colony Dr. Brower described as "dangling in trees right next to
farm fields "than at the colony located further up the mountain in a more 
intact forested area. 

Predictably, there was also no media coverage of the fact more monarchs
died this past winter in the portion of the El Rosario reserve that scientist's
have told us has the most intact forest.

Paul Cherubini
Placerville, Calif.


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