John V. Calhoun bretcal at
Mon Sep 29 17:51:24 EDT 1997

Dr. James Adams wrote:

 I can think of reasons for such introductions,
> such as a species having historically occurred in an area where it
> has since been extirpated by humans.  We would then be
> *reestablishing* populations that *should* exist.  Do others agree?

I indeed agree.  The reintroduction of the Schaus' Swallowtail onto 
mainland Florida is a good example.  HOWEVER, there is some speculation 
that old records from the mainland do not indicate that resident 
populations existed.  Rather, they may have been strays from populations 
on the Keys where the hostplants are native.  The hostplant, torchwood, 
may not be native to the mainland--again human intervention makes such 
conclusions nearly impossible.  More food for thought...  
>     One last point, however, that should be made is that such
> introductions are *going to occur*, even if totally regulated and no
> one purposely moves species around.  

Definately.  I suspect that some of the unusual records in Florida are 
the result of such "helpful" movements.  Papilio androgeus was possibly 
accidentally introduced into South Florida during the mid-1970's.  It 
hasn't been seen in the region for some time so it appears that this 
introduction did not take.  Another likely introduction is South 
American Electrostrymon sangala (the single Florida record was 
incorrectly believed to represent E. endymion).  Did it fly here on its 
own--doubtful; like so many other insect species intercepted each year 
by Customs at Miami and Tampa, it probably arrived as an incidental 
result of human activities. However, PURPOSELY and irresponsibly 
importing/moving extralimital species is another story...  
>     The modern age of human transportation has, by its very nature,
> muddied the picture of natural ranges/movements of an incredible
> number of species (including humans).  I would hate to be an
> archaeologist of another species hundreds of thousands of years from
> now trying to put together clear pictures of natural ranges of
> species.  Lets hope our informational resources last a long time!!



More information about the Leps-l mailing list