OUCH!!  Looks like it is time to "introduce" a new topic!  Accordingly,
how about introduced mollusc spp??  Many of the most successful spp on
the planet are not native to the place where they do the best at
whatever it is that they respectively do: eat algae, demolish gardens,
out-compete indigenous tree snails, etc...The super-ultra-common (and
alliterative to boot!) Litterina Litterea L, for example, is an import
from Europe , which they escaped from in the mid-1800s, to get  away
from all the hungry peole eating them.  Very quickly, they ruled the
mid-intertidal zone for thousands of miles!!  (Does anyone know the
details??)  I'm certain i'm not the only one who would like to hear the
"true story" of some of the more successful Molluscan introductions in
various parts of the world- or conversely, some which simply *didn't*
work out, for some reason or another.
        Do not assume everyone has heard about the more widely-disseminated
accounts: many like myself have heard fragments of much, but have rarely
partaken of the "Full Meal Deal" for any particular introduction.
 
                                                                                        -Ross Mayhew.