June Bailey, a reliable sheller, once found a live, fully adult Strombus
gigas (Queen Conch) in the shallow water in the Panama City, Florida area.
I trust her because she knows her stuff.
 
I have personally found, and many others have, too, Smaragdia viridis
(Emerald Nerites) in the same area. Both of these species are considered
Caribbean and do not occur in Florida north of the Keys, as far as I know,
except for this instance. I theorize that the veligers rode the Florida
Current up to its closest approach to land where they found a friendly
environment in a warm year and were able to settle and live. The Strombus
is probably a one-time fluke. It would have needed about five warm winters
to survive to adulthood in the shallow water there. (One of the awards at
the shell show in Panama City is called the "Frozen Dipnet Award" - for
local shells.) But the nerites are a thriving community, I believe.
 
I don't think it would be unusual to find the occasional Caribbean species
anywhere the Gulf Stream passes (as long as they have a veliger stage).
After all, there are documented stories of sea turtles turning up in
England (and I think even Portugal), having ridden the Gulf Stream all the
way.
 
Ain't nature wonderful?
Peggy
 
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                                  Peggy Williams
                                   Shell Elegant Tours
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