> You are not the only one to notice the rather sudden decline of Oliva
sayana
> on the U.S. East Coast.  When I moved to Jacksonville ten years ago, one
> could at times find literally thousands on a one mile long stretch of
beach
> here in the Jacksonville area.  This continued for several years. As time
> went
> on the numbers continued to decline to where you might see a hundred
> specimens each day on the same beach. Then it became you might see a
> hundred specimens or so in a year and now finally in 1999, not a single
> live specimen was seen. Over-collection is not a factor.
>
> I don't know the reason for the decline.  It may be a natural population
trend
> that happens every so many years. I personally suspect it is due to a
number
> of things added together (beach renourishments, increased water pollution,
> lack of food (the Donax population too has hit rock bottom) and natural
> factors.  Other beaches in the local area (although never having as large
a
> population of O. sayana) too are totally devoid of living shells.
>
> PS: Neverita duplicata populations are as high as ever along with Hastula
> salleana.
>
> You might want to see my
> http://home.sprynet.com/~wfrank/beach.htm
>
> Bill Frank
> 1865 Debutante Dr.
> Jacksonville, Florida 32246
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> [log in to unmask]
> --------------------
> Visit the Jacksonville Shell Club Home Page
> http://home.sprynet.com/~wfrank/jacksonv.htm
>
> ----- Original Message -----
> From: VanDenEnde-1, Oliver
> To: <[log in to unmask]>
> Sent: Thursday, December 23, 1999 3:40 PM
> Subject: Case of the missing olive shells
>
>
> > I've notices that in the 12 years that I have been collecting shells
along
> a
> > stretch of breach along the Florida east coast (between Cape Canaveral
and
> > Sebastian Inlet) that there are almost no olive shells (Oliva spp, esp.
> > Oliva syana) anymore.  You can rarely find a fresh specimen and what
does
> > wash up is old.  It does not appear to be related to an increased
> collection
> > rate (i.e. from more people picking them off the beach), because I have
> > access to beaches on Cape Canaveral Air Station which is off limits to
the
> > public and has equally low numbers of olives.
> >
> > I have noticed a similar trend in the numbers of lobed moon shells (
> > Polinices duplicatus).
> >
> > Please let me know of any research that has been conducted on the
> > distribution and abundance patterns of olive and moon shells along the
> > Florida coast.  I'd like to know if there really are seasonal or
> man-induced
> > changes taking place that affect these and other mollusk species.