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to Rob Dillon, who runs the Freshwater Gastro
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Hi Paul & All, Nov 10, 2011
Snails are around all year. So feeding peaks in Spring & Fall suggest that snails are a hunger diet; other food sparse then perhaps or inactive. Also I wonder if the stuffed effect is partly due to a long residence time in the gut.
Yt, DW
----- Original Message -----
From: Paul MacDonald
To: naturens@chebucto.ns.ca
Sent: Thursday, November 10, 2011 10:11 AM
Subject: Re: [NatureNS] Trout and Snails
Thanks to Fred and Dusan for the advice on a book.
And also Ulli for the parasitology note. It was not my favorite
course but I passed!
The book has been ordered and a good topic to study over winter
before the fishing times are on us again.
Fred mentioned reports of "Trout been stuffed with snails".
Seems that when we see snails in trout they are really stuffed with them.
None with a few. It would suggest that snails are either very available
to the trout or none. I will save some samples next time.
Thanks again
Paul
------------------------------------------------------------------------------
From: Frederick W. Schueler <bckcdb@istar.ca>
To: naturens@chebucto.ns.ca
Cc: Rob Dillon <dillonr@cofc.edu>
Sent: Thursday, November 10, 2011 9:49:32 AM
Subject: Re: [NatureNS] Trout and Snails
On 11/10/2011 7:16 AM, Dusan Soudek wrote:
> Aquatic "snails?" Do any species utilize anadromous fish species to
> take their larvae upstream, thus establishing and maintaining
> populations in headwater lakes and streams.
* not as far as I know. Snails are born alive or hatched from eggs in jelly, and don't have a specialized dispersal phase. They're thought to spread by sticking to the feet or plumage of Birds and then dropping off. Often there are striking instances of water bodies which lack aquatic snails. I'm copying this to Rob Dillon, who runs the Freshwater Gastropods of North America - http://fwgna.blogspot.com/ - and would know if any such early-life dispersal adaptations are known.
> This is quite common in the
> "snails'" cousins, the bivalve molluscs.
> I remember reading about a freshwater mussel species becoming extinct in
> N.B.'s Petitcodiac River, after the tidal dam/causeway in Moncton
> destroyed the salmon run there. I do wonder whether this species is back
> now that the dam is open again.
* we drove past there this summer, and regretted not having the time or low water that would be needed to search, but this was an isolated population (nearest was in New Hampshire - none in Maine) - of a short-lived species - Alasmidonta heterodon - see http://en.wikipedia.org/wiki/Dwarf_wedgemussel
> I have never come across a good review of this topic. The larvae of
> relatively immobile invertebrates literally hitching rides on highly
> mobile searun fish to travel hundreds of miles upstream...
* the species that has made big range expansion after coastal dams have been removed is Anodonta implicata, the Alewife Floater, which has the host suggested by its English name, and also uses shad as a host, and which has gone scores or hundreds of km upstream when dams have been removed. It used to get (rarely) as far upstream as Ottawa before the Seaway.
fred.
------------------------------------------------------------
Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinicola.ca/bmnhc.htm
Mudpuppy Night in Oxford Mills - http://pinicola.ca/mudpup1.htm
Daily Paintings - http://karstaddailypaintings.blogspot.com/
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
(613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
------------------------------------------------------------
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<DIV><FONT size=2>Hi Paul & All,
Nov 10, 2011</FONT></DIV>
<DIV><FONT size=2> Snails are around all year. So feeding
peaks in Spring & Fall suggest that snails are a hunger diet; other food
sparse then perhaps or inactive. Also I wonder if the stuffed effect is partly
due to a long residence time in the gut. </FONT></DIV>
<DIV><FONT size=2>Yt, DW</FONT></DIV>
<BLOCKQUOTE
style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px"
dir=ltr>
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=paulrita2001@yahoo.com href="mailto:paulrita2001@yahoo.com">Paul
MacDonald</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=naturens@chebucto.ns.ca
href="mailto:naturens@chebucto.ns.ca">naturens@chebucto.ns.ca</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, November 10, 2011 10:11
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NatureNS] Trout and
Snails</DIV>
<DIV><BR></DIV>
<DIV
style="BACKGROUND-COLOR: #fff; FONT-FAMILY: times new roman, new york, times, serif; COLOR: #000; FONT-SIZE: 12pt">
<DIV><SPAN>Thanks to Fred and Dusan for the advice on a
book.</SPAN></DIV>
<DIV><SPAN>And also Ulli for the parasitology note. It was not my
favorite</SPAN></DIV>
<DIV><SPAN>course but I passed!</SPAN></DIV>
<DIV><SPAN>The book has been ordered and a good topic to study over
winter</SPAN></DIV>
<DIV><SPAN>before the fishing times are on us again.</SPAN></DIV>
<DIV><SPAN>Fred mentioned reports of "Trout been stuffed with
snails".</SPAN></DIV>
<DIV><SPAN>Seems that when we see snails in trout they are really stuffed with
them.</SPAN></DIV>
<DIV><SPAN>None with a few. It would suggest that snails are either very
available</SPAN></DIV>
<DIV><SPAN>to the trout or none. I will save some samples next
time.</SPAN></DIV>
<DIV><SPAN>Thanks again</SPAN><BR>Paul</DIV>
<DIV><BR></DIV>
<DIV style="FONT-FAMILY: 'times new roman',
'new york', times, serif; FONT-SIZE: 12pt">
<DIV
style="FONT-FAMILY: 'times new roman', 'new york', times, serif; FONT-SIZE: 12pt"><FONT
size=2 face=Arial>
<HR SIZE=1>
<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Frederick W. Schueler
<bckcdb@istar.ca><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B>
naturens@chebucto.ns.ca<BR><B><SPAN style="FONT-WEIGHT: bold">Cc:</SPAN></B>
Rob Dillon <dillonr@cofc.edu><BR><B><SPAN
style="FONT-WEIGHT: bold">Sent:</SPAN></B> Thursday, November 10, 2011 9:49:32
AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [NatureNS]
Trout and Snails<BR></FONT><BR>On 11/10/2011 7:16 AM, Dusan Soudek
wrote:<BR>> Aquatic "snails?" Do any species utilize anadromous fish
species to<BR>> take their larvae upstream, thus establishing and
maintaining<BR>> populations in headwater lakes and streams.<BR><BR>* not
as far as I know. Snails are born alive or hatched from eggs in jelly, and
don't have a specialized dispersal phase. They're thought to spread by
sticking to the feet or plumage of Birds and then dropping off. Often there
are striking instances of water bodies which lack aquatic snails. I'm copying
this to Rob Dillon, who runs the Freshwater Gastropods of North America - <A
href="http://fwgna.blogspot.com/" target=_blank>http://fwgna.blogspot.com/</A>
- and would know if any such early-life dispersal adaptations are
known.<BR><BR>> This is quite common in the<BR>> "snails'" cousins, the
bivalve molluscs.<BR>> I remember reading about a freshwater mussel species
becoming extinct in<BR>> N.B.'s Petitcodiac River, after the tidal
dam/causeway in Moncton<BR>> destroyed the salmon run there. I do wonder
whether this species is back<BR>> now that the dam is open again.<BR><BR>*
we drove past there this summer, and regretted not having the time or low
water that would be needed to search, but this was an isolated population
(nearest was in New Hampshire - none in Maine) - of a short-lived species -
Alasmidonta heterodon - see <A
href="http://en.wikipedia.org/wiki/Dwarf_wedgemussel"
target=_blank>http://en.wikipedia.org/wiki/Dwarf_wedgemussel</A><BR><BR>> I
have never come across a good review of this topic. The larvae of<BR>>
relatively immobile invertebrates literally hitching rides on highly<BR>>
mobile searun fish to travel hundreds of miles upstream...<BR><BR>* the
species that has made big range expansion after coastal dams have been removed
is Anodonta implicata, the Alewife Floater, which has the host suggested by
its English name, and also uses shad as a host, and which has gone scores or
hundreds of km upstream when dams have been removed. It used to get (rarely)
as far upstream as Ottawa before the
Seaway.<BR><BR>fred.<BR>------------------------------------------------------------<BR>
Frederick W. Schueler & Aleta Karstad<BR>Bishops
Mills Natural History Centre - <A href="http://pinicola.ca/bmnhc.htm"
target=_blank>http://pinicola.ca/bmnhc.htm</A><BR>Mudpuppy Night in Oxford
Mills - <A href="http://pinicola.ca/mudpup1.htm"
target=_blank>http://pinicola.ca/mudpup1.htm</A><BR>Daily Paintings - <A
href="http://karstaddailypaintings.blogspot.com/"
target=_blank>http://karstaddailypaintings.blogspot.com/</A><BR>
RR#2 Bishops Mills, Ontario, Canada K0G 1T0<BR> on the Smiths Falls
Limestone Plain 44* 52'N 75* 42'W<BR> (613)258-3107 <bckcdb at
istar.ca> <A href="http://pinicola.ca/"
target=_blank>http://pinicola.ca/</A><BR>------------------------------------------------------------<BR>------------------------------------------------------------<BR><BR><BR><BR></DIV></DIV></DIV>
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<P class=avgcert align=left color="#000000">No virus found in this
message.<BR>Checked by AVG - <A
href="http://www.avg.com">www.avg.com</A><BR>Version: 10.0.1411 / Virus
Database: 2092/4007 - Release Date: 11/09/11</P></BLOCKQUOTE></BODY></HTML>
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