M. McMahon wrote:

> Hello All,
>
> I generally travel to south Florida during winter and summer months and I usually find the same species.  In Southeast Florida during the summer and winter months what species are more abundant? For example, what time of the year is Cassis Tuberosa, Strombus Costatus and Strombus Raninus most abundant?  I know feeding habits is a factor. Is spawning and locality a factor also?  I have been researching my books, however, the information is very general.  Are there any books on this particular subject or Internet resources? Any information would be appreciated.
>
> Regards,
> Monique
>
>
I doubt that molluscan species abundance varies much from winter
to summer here in Florida, although it definitely does in
multi-year cycles.

If you are collecting primarily fresh dead, as I do, there is
some seasonal variation as a result of the activity of
predators, especially octopus. Also, storm season (June-October)
roots out the burrowing species and exposes them to predators.
(A good thunderstorm cell will stir the bottom at 65', and a
hurricane tosses large wrecks at 130' like toys.)

 From year to year, certain species seem to "bloom" (currently
whelks and Atlantic murex?), and I think each species has a
cycle but I've never seen any proof or even any observations
outside of my own casual dive logs which cover too short a
period to establish a real pattern - I'd guess 50-60 years of
proper observations would establish some interesting cycles.

Octopus love Strombus and hunt them aggressively when Octopus
populations are high, but settle for clams when octopus
populations are low. A few years ago there was an octopus
"bloom" here in SoFla, and I collected hundreds of Strombus from
octopus middens. This year, there are not many octopus around,
so I think you will see less S. costatus this winter.

regards
m

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