The Chincoteague area underwent appreciable rearrangement of the
channels in the mid-1900's, so conditions that favored gigantism may
have changed somewhat.

Gigantism may (probably among other options) reflect abundant food,
extra long life, or a failure to mature, so that the individual is
still growing like a juvenile instead of putting lots of energy into
reproduction.  The latter may have several causes.  In parasitic
castration, the parasite feeds on gonads, which avoids killing their
host but also may prevent any hormonal signals to start putting less
energy into growth and more into reproduction.  In species with
seasonal cues for breeding, an individual living somewhere that
doesn't get the right cue likewise may keep right on growing instead
of reproducing.  For example, warm-water marine larvae may disperse
into places where the water temperature is fine for survival, but
rarely or never reaches the temperature that tells the animal that
it's time to breed.  A particularly problematic situation of this sort
comes from freshwater habitats downstream from dams.  If the water is
released from deep in the lake behind the dam, then it will be cool
year round and may never get warm enough to ce the breeding season; if
it comes from shallow in the lake it will, at least in summer, be
hotter than the river's normal temperature, and if it's a dam that
just turns the water on and off (e.g., hydroelectric to meet power
demand), without regard for the downstream impacts, then the
temperature, flow, oxygen, depth, and other features will vary
irregularly.


On Mon, Sep 3, 2012 at 9:02 PM, steve rosenthal <[log in to unmask]> wrote:
> Harry thanks for making that article accessible. i have been
> interested in that form for some time. would be interesting to know if
> they are still around there.
>
> in the bicentennial summer of 1976 i lived in  chincoteague as part of
> an organized summer marine science program. we had an outing for some
> free  beach time at Assateauge one afternoon, everybody hit the ocean
> beach, i went to the bay to look for shells, of course. in Toms cove i
> found two large urosalpinx that appeared to be this form, a mere
> 36-38mm or so but i assumed it was the same named form. i went back
> there years later but couldnt find any though i doubt i refound or
> even remembered the exact spot they came from.
>
> that number of 51.2 mm is familiar, it appears in several references,
> including on hardys gastropods.com website.
>
> i am wondering if anybody on conch-l has found the large urosalpinx themselves?
>
>
> Steve
>
>
>
> On 9/3/12, Harry Lee <[log in to unmask]> wrote:
>> Dear Eddy et al.,
>>
>> Dick Petit has reminded me that Urosalpinx cinerea form follyensis B.
>> Baker, 1951 was applied to members of a giant population of the
>> species occurring at Folly Creek, VA (Delmarva Peninsula, USA).
>>
>> I was able to find its original description at
>> <http://www.biodiversitylibrary.org/item/34889#page/95/mode/1up>.
>> Note that the holotype measures 51.2 mm and is at the ANSP, quite
>> possibly in the same drawer as that of Fusus cinereus Say, 1822.
>>
>> My feeling is that the Baker taxon is likely an ecophenotype rather
>> than being genetically isolated.
>>
>> Beside this Baker (Bernadine Barker, or "Bunny," see
>> <http://www.biodiversitylibrary.org/item/34226#page/64/mode/1up>),
>> there were three (3) others who have made contributions to our
>> knowledge of western Atlantic marine mollusks according to Malacolog
>> 4.1.1: Frank Collins (1867-1942); Horace Burrington, husband of
>> Bunny, (1889-1971); and Patrick (living, well, and working in FL).
>> Biographical data are drawn from 2,400 Years of Malacology (9th
>> Edition) by Coan, Kabat, and Petit; see
>> <http://www.malacological.org/publications/2400_malacology.php>.
>>
>> Baker, B. B. 1951. Interesting shells from the Delmarva Peninsula.
>> The Nautilus 64: 73-77, pl. 5. Jan.
>>
>> Harry
>>
>> Sun, 2 Sep 2012 14:19:24 -0400
>>
>> From:         Eddy WILMET <[log in to unmask]>
>> Subject:
>> <http://www.listserv.uga.edu/cgi-bin//cgi-bin/wa?A2=ind1209A&L=conch-l&D=0&H=0&O=T&T=1&P=339>Size
>>
>>
>> Last week I've been collecting Urosalpinx cinerea in the Oosterschelde-
>> delta in the Netherlands where it's invasive, together with Ocinebrellus
>> inornatus (which is almost a 200km expansion for this species to the North
>> as normally its habitat is French-Brittany, Atlantic Coast)
>> The presence of the Urosalpinx cinerea is overwhelming with large
>> specimens over 25/30 mm. Can anyone give me some considerations about the
>> growing rate of this species and maximum sizes of the American specimens.
>> Thanks,
>> Eddy
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
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--
Dr. David Campbell
Visiting Professor
Department of Natural Sciences
Gardner-Webb University
Boiling Springs NC 28017

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