I've done a small number (<15) of feeing trials with Rumina decollata
(unpublished), and found that they usually seem to prefer eating lettuce
over eating Helix aspersa. In California, where I did the trials, they also
seemed to prefer some local snails over Helix aspersa. The 2 cautions I
would take from these observations are (1) Rumina decollata itself may also
eat your plants, and (2) Rumina decollata may pose a threat to native,
non-pest species. The cynic in me suspects that the ad in the gardening
magazine did not mention these two ideas.
   -Tim-

Timothy A. Pearce, Ph.D., Curator of Mollusks
Delaware Museum of Natural History
Box 3937, 4840 Kennett Pike        302-658-9111 x319
Wilmington, DE 19807-0937, USA    [log in to unmask]

-----Original Message-----
From: Monfils, Paul [mailto:[log in to unmask]]
Sent: Wednesday, 26 April, 2000 10:30
Subject: Using Snails for Snail Control??

During lunch yesterday I picked up a gardening magazine belonging to one of
my colleagues, and as I flipped through it I came upon a large full color
picture of a snail.  I figured the attached article was about controlling
snails that feed on garden plants.  And so it was - only it wasn't exactly
an article, it was an advertisement - and the pictured snail was not one of
the species that need to be controlled.  Rather, it was a carnivorous snail
that was being offered for sale as a means of controlling Helix and other
molluscan garden pests.  I visited their web site (www.biopest.com).  The
snail they are selling is Rumina decollata, which they list as "decollate
predatory snail".  Is this a reasonable approach to controlling snails in
your garden?  Or could the importation of such a species result in mass
destruction of the local molluscan fauna?
Paul M.