At 20:36 08-09-1998 -0700, you wrote:
>Over the last several days there has been quite an informative
>discussion on dredging.  I am curious about trapping shells.  Obviously,
>the take from this method would be small relative to dredging, but I've
>often thought it would be interesting to set some sort of baited trap in
>an intertidal or subtidal area and see what one comes up with.  Any
>thoughts on the type of trap that might work best, or area that might be
>most productive? What kinds of shells might one expect to capture this
>way?  Oliva, Strombus, Conus, Murex?
>
>Chris Brown
>
 
        Hi Chris!!
 
        Here in Portugal fishermen use bait, in this case the bivalve Cerastoderma
edule (commom name: Berbigão), to capture Hexaplex trunculus. The methode
is very simple: first they put a had full of the live (close valved)
bivalves in what they locally call "carteirinhas" (little wallets), these
are maid of plastic and have and opening of about 1.5 mm per squre cube and
mesure about 120 mm hight for 90 mm wide; then they just place them for a
day or so on the sea flor; after this they just pull them back on the boat
and collect the H. trunculus that are atached to the little wallets eathig
the bivalves (or just still trying to open there valves, to do just so).
This simple methode is very very eficient, and you can collect big numbers
H. trunculus in a sigle little wallet. The hole fishing divice can be maid
of more the a hundred little wallets held together by a single roupe, so
you can imagen all the Murex that can be collected in a 24 hour cicle ...
        Unfortunally this traditional methode of catch is in decay and maybe in a
few generations we woun´t eaven see it action, but just try and imagen how
it should work when seeing it in a museum ... 
 
        Hope this turns out ok, the simple fishing divice I just mentioned:
           
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        Regards,
 
        Carlos