[leps-talk] Credible sources

[Charles Bordelon]

"Go fishing my boy..."  Man, some people just don't get it.  Can someone
direct me to the nearest Monarch Intervention Class?  I feel "one of my
turns coming on."  Now PC wants to get honest.  I'm gonna hurl.  Pink F.
----- Original Message -----
From: "Paul Cherubini" <monarch at saber.net>
To: <TILS-leps-talk at yahoogroups.com>
Cc: <leps-l at lists.yale.edu>
Sent: Thursday, October 09, 2003 5:13 PM
Subject: Re: [leps-talk] Credible sources


> Patrick Foley wrote:
>
> > If we are to get a clearer and more honest picture of the Monarch's
> > status and prospects, we need a _quantitative_ description of the
> > changes in critical winter habitat.   We need to ask 1) how does monarch
> > winter survivorship depend on the amounts of land in old growth,
> > secondary growth,  clear cut and milpas?
>
> Pat, I'm not sure what you mean by "critical winter habitat"?   None
> of the monarch forests today in Mexico are virgin 120+ year old
> growth type forests. They are are all young 30 - 60 year old regrowth
> despite their pristine-like appearance
> http://www.saber.net/~monarch/chincuadis.JPG  And for decades this
> massively altered forest has been sufficiently good habitat to support the
> massive monarch migration / overwintering phenomenon we still see today,
> with no sign of the population increasing or decreasing
> http://www.saber.net/~monarch/mexicopop.jpg   Likewise, the massive
> crop monocultures of the upper Midwest
> http://www.saber.net/~monarch/iowaland.jpg have provided sufficiently
> good breeding habitat to support the massive monarch migration.
>
> Have the monarchs abandoned any of the mountains in Mexico due
> to any cause such as forest alteration?  NO.  Have the numbers of
> monarchs decreased on any of the mountains?  NO.   Have certain
> forest densities / structures been conclusively linked to butterfly
> survivorship or mortality during storms / freezes? NO.  After winters with
> high storm related mortality, such as 1981-82, 1991-92, 1995-96 and
> 2000-01, was the size of the butterfly population returning to Mexico the
> following autumn always average or above average in size? YES.
> After winters such as 2001-2002 with a catastrophically high level (75%)
> of storm related mortality was the size of the butterfly population
> returning to Mexico the following autumn average in size?
> YES.  Thus, in view of these facts, what biological justification is there
> to describe the overwintering habitat in Mexico as "critical", "fragile",
> etc. anymore than if someone should describe the summer breeding crop
> monoculture habitat of the monarch
> http://www.saber.net/~monarch/iowaland.jpg
> as "critical" and "fragile." And considering that the size of the
> overwintering population in Mexico has remained stable despite radical
> changes in forest age and structure (from all virgin to all
> regrowth) do we really need to know precisely how forest age and
> structure affects butterfly survivorship in order to "get a clearer
> and more honest picture of the Monarch's status and prospects"?
> Or is it more reasonable to conclude the monarch migration is no
> imminent danger of extinction?
>
> Paul Cherubini
>
>
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