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beachpeople said:
Just before you go upstairs to customs at the airport, there is a glass case with examples of what not to try and take home. There it is, a big conch shell.


Bringing a conch shell back in to the US is legal, depending on where you are coming from.

From What you need to know from the U.S. Fish and Wildlife Service.
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You may import queen conch into
the United States from parts of the
Caribbean not subject to the trade
prohibitions, provided it is allowed
by the country of export and it is
accompanied by any required CITES
documents. Countries from which
import may be allowed include: Anguilla,
Aruba, Bahamas, Belize, Bermuda,
Brazil, British Virgin Islands, Cayman
Islands, Colombia, Costa Rica, Grenada,
Guadeloupe, Guatemala, Jamaica,
Mexico, Montserrat, the Netherlands
Antilles, Nicaragua, Panama, Saint Kitts
and Nevis, Saint Lucia, Saint Vincent and
the Grenadines, Turks and Caicos, and
Venezuela.