[LEPS-L:7913] From extinction to salvation

[Paul Cherubini]

Pat Foley wrote in regard to butterfly releases: 

> I believe that the majority of population biologists interested in the
> problem tend to agree with Opler, Glassberg, Pyle and others that 
> there are serious potential dangers to butterfly release.
> Most ecologists are environmentalists from bitter experience and careful
> analysis. It is simply not true that ecologists are fudging their data, lying
> about their conclusions or intentionally misleading the public.

In Sept. 1996 Dr.'s Lincoln Brower, Chip Taylor and Karen Oberhauser
explained in BioScience the reason they are so emphatically against 
mailing wild caught monarchs across the Rocky Mountains for butterfly
releases is because such transfers could cause disease epidemics and in 
turn lead to the extinction of the monarch migration. Below is exactly what
they wrote:

"recurrent epidemics could lower the monarchs' overwintering population
sizes to the point at which known or unknown ecological factors might
become devastating...[bird] predation during an extreme population low
might reduce monarch populations to levels at which the numbers of
survivors are insufficient to recolonize the summer breeding range,
followed by collapse of the migration-overwintering phenomenon".

Remarkably, after claiming mailing monarchs across the Rocky
Mountains for release could cause the "collapse of the
migration-overwintering phenomenon" Lincoln Brower is now
promoting the idea that natural monarch movement across the
Rocky Mountains may actually prevent the western monarch from
going extinct!

Below is what Lincoln Brower said during a tape recorded lecture
at the Pacific Grove Museum of Natural History two weeks ago (Nov. 5):

"I now think that California is ultimately dependent upon replenishing from
Mexico. If you go back about 5 years ago there was this progressive
decline in monarchs in California and they were really, really low and
all of a sudden the next fall they were back again. That spring before
the recovery, there was a 1600 mile displacement of the Spring
Warbler [bird] migration to the west. And I think what happened was 
that as with the birds, the monarchs got blown westward and that is 
how California probably gets reinoculated from the monarchs coming
up from Mexico. And I suspect that happens historically often enough 
that it is very possible monarchs in California would go extinct if they 
didn't periodically get injections from Mexico."

Paul Cherubini

 
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