gene pool and releases

Paul Cherubini cherubini at
Fri Jun 15 18:43:28 EDT 2001

Bob Parcelles wrote:

> I personally feel, as a populations biologist that
> release may have an effect on the gene pool and and
> should be used intelligently (which it is not!).

Pat Foley wrote:

> It is much harder to study the long-term evolutionary effects of lost
> geographical reproductive isolation though they are likely to be profound.

About 90% of all wedding and school releases involve just monarchs or painted
ladies. Five genetic studies comparing eastern and western USA monarchs and 
two studies comparing east coast  and west coast Painted Ladies failed to find
differences* Also, Monarchs and Painted Ladies exist in all 48 mainland states 
of the USA, and in every county within every state. Ditto for their larval host 
plants (with rare exceptions) Thus no geographical reproductive isolation. 

By contrast, NABA's  tells the public on its website:

"Releasing commercially-raised butterflies into the environment is an act of
  anti-environmental terror"
"inappropriately mixes genetically distinct populations of the same species"
"may disrupt migratory behavior of native butterflies"
"confuses scientific studies of butterfly migrations"

> It would be good to get more research done on disease transmission
> in butterflies, but who would fund it? None of the commercial butterfly
> releasers have stepped forward, and it seems largely their responsibility.

The largest monarch butterfly breeder in the USA (with the odd name of
Swallowtail Farms) has gone a step further - this company has their monarch 
breeding stock inspected for parasites and pathogens at regular intervals by 
one of the top insect pathologists in the country - Dr. Harry Kaya - a senior
entomology professor at the University of California, Davis. 

I am unaware of any insect pathologist that is opposed to releases 
of monarchs and painted ladies within the 48 US mainland states. 
Dr, Kaya, as a matter of fact, arranged to have monarchs shipped to
him from 250 miles away for release at his own daughter's wedding. 

By contrast, NABA's  tells the public on its website that releases:

"spreads diseases to natural populations"

Paul Cherubini, Placerville, Calif.

*one study found a statistically significant, but quantitatively small 
difference in the virulence of a monarch parasite in one monarch sample 
from California vs one sample in Mexico, but this parasite only has "minor 
effects on fitness and reproduction" according to the authors.


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