Government views Monarch Butterfly Releases as a threat to Western Milkweeds

[Paul Cherubini]

Bob Kriegel wrote:

> If monarchs don't use the species in question as hosts or rarely use them
> the proposed regulations will not do anything to protect those plants.
> Period.   If monarch larvae do feed on the plants but do not kill them or
> reduce their long term viability then they are also of no danger to the
> plants.  If someone knows the answers to these two questions please speak
> up.

Do we really need to spend years of time and hundreds of thousands
of dollars trying to answer these questions in order to determine if 
monarch releases are a danger to rare milkweed plants?

Several years ago some commercial monarch breeders made the claim that
releasing monarchs was good for conservation because it increased the size 
of wild monarch populations.  Immediately the academic community pointed 
out how flawed this claim was based on simple mathematical models. 

Now we are faced with a situation in which members the academic community 
(Dr. Karen Oberhauser, Dr. Chip Taylor and Dr Wayne F. Wehling of
the USDA) are suggesting that research needs to be conducted to determine 
if releasing monarchs could kill or reduce the long term viability of certain
rare milkweed plants.

Now how come we don't see voices from the academic community immediately
suggesting that we examine the legitimacy of these concerns using simple 
mathematical models?  

Example:
Approximately 200,000 monarch butterflies are shipped interstate to all
parts of the USA each year by butterfly breeders. The number of monarchs
shipped to an individual state roughly mirrors the human population
of that state.  Thus in Arizona we have a human population of 4,200,000 vs a
national human population of 270,000,000 = approximately 3,111 monarchs will
potentially be shipped to Arizona for release, mostly during the period
April to October = 444 monarchs per month for seven months.

Now does it make any common sense to contemplate the potential
impact of 444 monarchs shipped to Arizona every month against a background
monarch population numbering in the tens to hundreds of thousands
and a background population of queen butterflies numbering
in the hundreds of thousands or a background population of milkweed bugs
and other invertebrate herbivores of milkweeds numbering in the six or 
seven figures?  

Paul Cherubini

 
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