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Index of Subjects
Index of Subjects ---2114655128-1468491976-1320934267=:82255 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Thanks to Fred and Dusan =A0for the advice on a book.=0AAnd also Ulli for t= he parasitology note. It was not my favorite=0Acourse but I passed!=0AThe b= ook has been ordered and a good topic to study over winter=0Abefore the fis= hing times are on us again.=0AFred mentioned reports of "Trout been stuffed= with snails".=0ASeems that when we see snails in trout they are really stu= ffed with them.=0ANone with a few. It would suggest that snails are either = very available=0Ato the trout or none. I will save some samples next time.= =0AThanks again=0APaul=0A=0A=0A________________________________=0AFrom: Fre= derick W. Schueler <bckcdb@istar.ca>=0ATo: naturens@chebucto.ns.ca=0ACc: Ro= b Dillon <dillonr@cofc.edu>=0ASent: Thursday, November 10, 2011 9:49:32 AM= =0ASubject: Re: [NatureNS] Trout and Snails=0A=0AOn 11/10/2011 7:16 AM, Dus= an Soudek wrote:=0A>=A0 Aquatic "snails?" Do any species utilize anadromou= s fish species to=0A> take their larvae upstream, thus establishing and mai= ntaining=0A> populations in headwater lakes and streams.=0A=0A* not as far = as I know. Snails are born alive or hatched from eggs in jelly, and don't h= ave 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 striki= ng instances of water bodies which lack aquatic snails. I'm copying this to= Rob Dillon, who runs the Freshwater Gastropods of North America - http://f= wgna.blogspot.com/ - and would know if any such early-life dispersal adapta= tions are known.=0A=0A> This is quite common in the=0A> "snails'" cousins, = the bivalve molluscs.=0A> I remember reading about a freshwater mussel spec= ies becoming extinct in=0A> N.B.'s Petitcodiac River, after the tidal dam/c= auseway in Moncton=0A> destroyed the salmon run there. I do wonder whether = this species is back=0A> now that the dam is open again.=0A=0A* we drove pa= st there this summer, and regretted not having the time or low water that w= ould 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=0A=0A> I hav= e never come across a good review of this topic. The larvae of=0A> relative= ly immobile invertebrates literally hitching rides on highly=0A> mobile sea= run fish to travel hundreds of miles upstream...=0A=0A* the species that ha= s made big range expansion after coastal dams have been removed is Anodonta= implicata, the Alewife Floater, which has the host suggested by its Englis= h 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.=0A=0Afred.=0A-----------------------= -------------------------------------=0A=A0 =A0 =A0 =A0 Frederick W. Schue= ler & Aleta Karstad=0ABishops Mills Natural History Centre - http://pinicol= a.ca/bmnhc.htm=0AMudpuppy Night in Oxford Mills - http://pinicola.ca/mudpup= 1.htm=0ADaily Paintings - http://karstaddailypaintings.blogspot.com/=0A=A0 = =A0 RR#2 Bishops Mills, Ontario, Canada K0G 1T0=0A=A0 on the Smiths Falls L= imestone Plain 44* 52'N 75* 42'W=0A=A0 (613)258-3107 <bckcdb at istar.ca> = http://pinicola.ca/=0A-----------------------------------------------------= -------=0A------------------------------------------------------------ ---2114655128-1468491976-1320934267=:82255 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable <html><body><div style=3D"color:#000; background-color:#fff; font-family:ti= mes new roman, new york, times, serif;font-size:12pt"><div><span>Thanks to = Fred and Dusan for the advice on a book.</span></div><div><span>And a= lso 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 ordere= d and a good topic to study over winter</span></div><div><span>before the f= ishing times are on us again.</span></div><div><span>Fred mentioned reports= of "Trout been stuffed with snails".</span></div><div><span>Seems that whe= n we see snails in trout they are really stuffed with them.</span></div><di= v><span>None with a few. It would suggest that snails are either very avail= able</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=3D"font-size: 12pt; font-family: 'times new roman', 'new york', times, serif; "><div style=3D"font-size: 12pt; font-family: 't= imes new roman', 'new york', times, serif; "><font size=3D"2" face=3D"Arial= "><hr size=3D"1"><b><span style=3D"font-weight:bold;">From:</span></b> Fred= erick W. Schueler <bckcdb@istar.ca><br><b><span style=3D"font-weight:= bold;">To:</span></b> naturens@chebucto.ns.ca<br><b><span style=3D"font-we= ight: bold;">Cc:</span></b> Rob Dillon <dillonr@cofc.edu><br><b><span= style=3D"font-weight: bold;">Sent:</span></b> Thursday, November 10, 2011 = 9:49:32 AM<br><b><span style=3D"font-weight: bold;">Subject:</span></b> Re:= [NatureNS] Trout and Snails<br></font><br>On 11/10/2011 7:16 AM, Dusan Sou= dek wrote:<br>> Aquatic "snails?" Do any species utilize anadromo= us fish species to<br>> take their larvae upstream, thus establishing an= d 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 stri= king instances of water bodies which lack aquatic snails. I'm copying this = to Rob Dillon, who runs the Freshwater Gastro