Mexico monarch smuggling math

Paul Cherubini cherubini at
Wed Oct 11 07:34:08 EDT 2000

Roughly 250,000 monarchs are raised and sold by commercial 
breeders for wedding/memorial releases in the 
USA each year. This "industry" reached a saturation point 
last summer when the supply of butterflies exceeded demand 
for the first time and some breeders had to let unsold butterflies
go free.

>From Nov 15- March 15 there are 100,000,000 monarchs 
overwintering in Mexico in reproductive diapause. Chip Taylor 
told us a few days ago at least 50,000,000 of these die at
the roosts of natural causes without breeding. This is a
mortality rate of 416,667 butterflies PER DAY.

Now even if every single one of the 250,000 monarchs
sold by USA commercial interests was smuggled in from
the overwintering roosts in Mexico, it would represent only
0.005% of the overwintering population. Not exactly
a "catastrophic" loss.

By contrast, there have been winters such as 1991-92 when
snow and ice storms were so severe in Mexico that
Lincoln Brower said in Science magazine: "4 out of 5
colonies I visited were practically wiped out."
And what were the consequences of this catastrophic mortality?
The very next winter monarch populations in Mexico were
back to normal (100 million).

Paul Cherubini, Placerville, Calif.

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